building america special research project: high-r...
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Building America Special Research Project High-R Walls Case Study Analysis Research Report - 0903 March 11 2009 (Rev June 8 2011) John Straube and Jonathan Smegal
Abstract
Many concerns including the rising cost of energy climate change concerns and demands for increased
comfort have lead to the desire for increased insulation levels in many new and existing buildings More building codes are being modified to require higher levels of thermal control than ever before This
report considers a number of promising wall systems that can meet the requirement for better thermal control Unlike previous studies this one considers performance in a more realistic matter including
some true three-dimensional heat flow and the relative risk of moisture damage
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A Introduction
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2 SCOPE
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1 WALL ASSEMBLIES REVIEWED
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Table 1 Criteria comparison matrix
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Figure 1 Plan view of wall section for Therm simulation
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Figure 2 Top plate simulation with 8rdquo of wall
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Table 3 R-values for analyzed wall systems
22 Hygrothermal Analysis
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Figure 9 Winter time sheathing relative humidity for Case 1 and Case 2
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Figure 10 Winter air leakage condensation potential for Case 1 and Case 2
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Figure 11 Winter air leakage condensation potential for Case 1 and Case 9
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Figure 14 Winter air leakage condensation potential for Case 4 and Case 10
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Figure 15 Installation of high density spray foam in an Offset Framed Wall in a cold climate
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Figure 16 Winter time air leakage condensation potential for Case 5 and Case 11
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Figure 17 Winter time sheathing relative humidity for Case 8
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Figure 18 Winter air leakage condensation potential for Case 8
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Figure 19 Inward vapor drive relative humidity of poly or GWB for Case 1 Case 2 and Case 9
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Figure 22 Inward vapor drive relative humidity of poly or GWB for Case 8
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Figure 23 Inward vapor drive relative humidity of poly or GWB for Cases 5 8 and 11
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Figure 24 Drying Curves for Case 1 and Case 2
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Figure 26 Drying curves for Case 8
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Figure 29 Standard construction practice
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Figure 30 Therm modeling of Case 1 - 2x6 construction
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Figure 31 Advanced framing construction
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Figure 32 Therm modeling of Case 2 advanced framing with 1 XPS insulated sheathing
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Figure 33 2x6 wall construction with interior strapping
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Figure 34 Therm analysis of horizontally strapped wall
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Figure 35 Double stud wall
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Figure 37 Truss wall construction
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Figure 38 Therm results of the truss wall
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152 Moisture Control
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Table 10 Calculated R-value for a Sips wall system
162 Moisture Control
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Figure 42 Nine inch foam ICF with five inches of EPS
Figure 43 Fifteen inch foam ICF with five inches of EPS
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Figure 44 2x6 wall construction with spray foam insulation
181 Thermal Control
13131313 1313131313 13131313131313
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30 Forest St Somerville MA 02143
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Figure 45 Therm modeling of spray foam wall and rim joist
13 amp amp+1+
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Table 11 Therm results of spray foam insulation analysis
182 Moisture Control
13 $
1313 13
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30 Forest St Somerville MA 02143
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113 13 13 13
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183 Constructability and Cost
13 13 13 13
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184 Other Considerations
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19 Case 9 Hybrid Wall Insulation ndash Flash and Fill
13 $1313
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 46 Hybrid wall construction with 2 spray foam and fibrous fill
191 Thermal Control
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30 Forest St Somerville MA 02143
Figure 47 Therm analysis of hybrid wall system
Table 12 Calculated R-value for a hybrid wall system
192 Moisture Control
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193 Constructability and Cost
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194 Other Considerations
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30 Forest St Somerville MA 02143
13 13
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110 Case 10 Double Stud Wall with Spray Foam
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Figure 48 Double stud wall with 2 of spray foam and cellulose fill
1101 Thermal Control
$) 13
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Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 49 Therm analysis of double stud wall construction with spray foam
Table 13 Calculated whole wall R-value for a double stud wall system with 2rdquo spray foam
1102 Moisture Control
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1103 Constructability and Cost
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30 Forest St Somerville MA 02143
1104 Other Considerations
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30 Forest St Somerville MA 02143
Figure 50 Offset frame wall construction with exterior spray foam
1111 Thermal Control
131313 13 1313131313
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13 13 13 13 13 13 13
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30 Forest St Somerville MA 02143
Figure 51 Therm analysis of an offset truss wall with exterior spray foam
Table 14 Calculated whole wall R-value for an offset framed wall with exterior spray foam
1112 Moisture Control
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$($( $$
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1114 Other Considerations
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112 Case 12 Exterior Insulation Finish System (EIFS)
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30 Forest St Somerville MA 02143
Figure 52 Wall construction using the EIFS cladding system
1121 Thermal Control
1313 1313
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30 Forest St Somerville MA 02143
Figure 53 Thermal analysis of an EIFS wall system
Table 15 Calculated whole wall R-value for a EIFS wall system with 4rdquo of EPS
1122 Moisture Control
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1123 Constructability and Cost
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1124 Other Considerations
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D Conclusions
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Table 16 Summary of all calculated R-values
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Table 17 Hours of potential winter time air leakage condensation
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Table 18 Wall Comparison Chart
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E Works Cited
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Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
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A Introduction
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30 Forest St Somerville MA 02143
2 SCOPE
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3 APPROACH
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B Analysis
1 WALL ASSEMBLIES REVIEWED
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2 ANALYSIS CRITERIA
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30 Forest St Somerville MA 02143
Table 1 Criteria comparison matrix
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21 Heat flow analysis
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Figure 1 Plan view of wall section for Therm simulation
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30 Forest St Somerville MA 02143
Figure 2 Top plate simulation with 8rdquo of wall
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Figure 4 Plan section of rim joist floor joists and fiberglass batt insulation
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30 Forest St Somerville MA 02143
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13 13 1313131313131313
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Figure 5 Common Convective Heat Flow Paths in Enclosures
131313 131313131313 131313
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30 Forest St Somerville MA 02143
(
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Table 2 Conductivity values used for two dimensional heat flow analysis
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Building Science Corporation 6 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
131313341313131313
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Figure 6 Typical framing 16oc - 9 framing factor
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Figure 7 Actual average framing factor of 23 in standard construction
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Building Science Corporation 2 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 3 R-values for analyzed wall systems
22 Hygrothermal Analysis
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30 Forest St Somerville MA 02143
13
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221 Moisture Balance
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Figure 8 Moisture balance
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
222 Wintertime Condensation
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Table 4 Vapor control strategies and permeance values for Case 1 and 2
Building Science Corporation 11 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 9 Winter time sheathing relative humidity for Case 1 and Case 2
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30 Forest St Somerville MA 02143
Figure 10 Winter air leakage condensation potential for Case 1 and Case 2
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30 Forest St Somerville MA 02143
Figure 11 Winter air leakage condensation potential for Case 1 and Case 9
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Figure 12 Winter time sheathing relative humidity for Case 3 Case 4 and Case 5
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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Figure 13 Winter air leakage condensation potential for Case 3 Case 4 and Case 5
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Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 14 Winter air leakage condensation potential for Case 4 and Case 10
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 15 Installation of high density spray foam in an Offset Framed Wall in a cold climate
13
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 16 Winter time air leakage condensation potential for Case 5 and Case 11
13 $$
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Building Science Corporation +- wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 17 Winter time sheathing relative humidity for Case 8
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Building Science Corporation - wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 18 Winter air leakage condensation potential for Case 8
223 Summer Inward Vapor Drives
13 13 131313
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1313 13 $13
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Building Science Corporation -+ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 19 Inward vapor drive relative humidity of poly or GWB for Case 1 Case 2 and Case 9
13$13 131313
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Figure 20 Inward vapor drive relative humidity of poly or GWB for Case 3 Case 4 and Case 5
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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Figure 21 Inward vapor drive relative humidity of poly or GWB for Case 4 and Case 10
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 22 Inward vapor drive relative humidity of poly or GWB for Case 8
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30 Forest St Somerville MA 02143
Figure 23 Inward vapor drive relative humidity of poly or GWB for Cases 5 8 and 11
224 Wall Drying
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Building Science Corporation 02 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 24 Drying Curves for Case 1 and Case 2
13131313 13 13
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Figure 25 Drying curves for Case 3 Case 4 and Case 5
13 1313
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 26 Drying curves for Case 8
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Figure 27 Drying Curves for Case 4 and Case 10 with and without a poly vapor barrier
131313131313 1313 131313
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Building Science Corporation 30 Forest St Somerville MA 02143
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Figure 28 Drying Curves for Case 5 and Case 11
23 Enclosure Durability
13 13 13
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24 Buildability
13 1313
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
25 Material Use
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1313131313
131313$
26 Cost
13 131313131313
1313$1313131313
13131313 1313
13$13amp1313 213
1313 )+$1313 13)-$+
1313$13131313 1313131313
131313$
C Results
1 CASE 1 STANDARD CONSTRUCTION PRACTICE
131313131313--0130(13
13131301313131313133 13$)-2
131313 13131313$
Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 29 Standard construction practice
111 Thermal Control
13) amp( 13
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13 $ 13 13
13 13
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Building Science Corporation - wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 30 Therm modeling of Case 1 - 2x6 construction
1313 13 13 131313 (-$13
13 131313 1313 13
131313) )13131313131313(-131313
13131313131313131313
13 13131313131313131313)+
13)-13131313131313 13
13
Table 5 Summary of R-value results from Therm modeling for Case 1
1313131313131313131313
131313 131313 13 13
13 1313131313
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112 Moisture Control
1313131313 13131313 13
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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113 Constructability and Cost
13
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114 Other Considerations
13
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131+13
amp 13
13amp
12 Case 2 Advanced framing with insulated sheathing
1313
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Building Science Corporation 0 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 31 Advanced framing construction
121 Thermal Control
131313 13$13 1313
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$$)amp $$)13$$13 13) 13
1313131313 1313
131313(-(13$amp-( 1313amp
+(13$13$1313$1313amp13
1313131313 1313
131313 1313
13131313131313
131313amp1313 13
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 32 Therm modeling of Case 2 advanced framing with 1 XPS insulated sheathing
amp $ $ 13 + 2 3$$35
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Table 6 Summary of R-value results from Therm modeling for Case 2
122 Moisture Control
$
$$$
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Building Science Corporation 00 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
131313$ 1313
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2 131313
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123 Constructability and Cost
131313131313
13130$
13-$131313
131313(13
$$13131313
13 1313
124 Other Considerations
amp 1313
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131313$1313 13
1313
13 Case 3 Interior 2x3 horizontal strapping
13 $
13$
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 33 2x6 wall construction with interior strapping
131 Thermal Control
1313 1313131313
1313131313 amp
1313131313 1313
131313 13 13131313
1313 1313131313
1313 1313 1313131313
13131313 13
13 13131313$
131313 13
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 34 Therm analysis of horizontally strapped wall
13$13-amp0)132amp 13$
3-1 1amp13 13
amp 13 13amp
Table 7 Calculated R-value of an interior horizontal strapped wall
132 Moisture Control
13
(1313$amp
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13 $amp
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Building Science Corporation 1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 13
133 Constructability and Cost
1313$
13 13
1313
134 Other Considerations
13
131313
13
14 Case 4 Double Stud
1313
131313
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 35 Double stud wall
141 Thermal Control
13
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30 Forest St Somerville MA 02143
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Figure 36 Therm model of the double stud wall
Table 8 Calculated R-value of a double stud wall
142 Moisture Control
13131313
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131313$13
131313
13amp 0++ 13$-
1313$
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Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13
13)amp 13
13 1313
13
13
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143 Constructability and Cost
13
amp 13
144 Other Considerations
13 13
131313
13 1313
15 Case 5 Truss Wall
1313
13 13131313
13 13 13
131313amp
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 37 Truss wall construction
151 Thermal Control
1313
13 13(
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amp
13
1313
)-13
131313
13
13 $)
13 13
13131313
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 38 Therm results of the truss wall
Table 9 Calculated R-value for truss wall
152 Moisture Control
13
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13 1313
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30 Forest St Somerville MA 02143
153 Constructability and Cost
13
13131313
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$ 13
154 Other Considerations
13 $$
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)
16 Case 6 Structural Insulated Panel Systems (SIPs)
131313
13 13$13 13
amp
Figure 39 SIPs wall construction
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
161 Thermal Control
13 13
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13 $ (
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27( $ amp03)4 13
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Figure 40 Therm results of SIPs panel analysis
Table 10 Calculated R-value for a Sips wall system
162 Moisture Control
13 $ $ amp
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)
Building Science Corporation 33 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($$
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163 Constructability and Cost
$amp $$$$ $
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+amp
164 Other Considerations
()($$$((
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17 Case 7 Insulated Concrete Forms (ICFs)
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 41 ICF wall construction
171 Thermal Control
1313
1313 1313
131313 (
+$)$13 13($
amp)$)
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 42 Nine inch foam ICF with five inches of EPS
Figure 43 Fifteen inch foam ICF with five inches of EPS
13 13 1313
13 1313131313$13$1313
1313amp1313 13 1313
13131313$amp
172 Moisture Control
1313131313131313 13$amp131313
131313 13amp13
$ 13$1313$13ampamp
13 1313$1313131313
131313amp13
1313131313 13amp
173 Constructability and Cost
13131313 $1313$13$ 13
13 13$1313amp13$13
1313 amp13 13
13 13 1313$
13$13 13$131313
131313 1313 13$amp
174 Other Considerations
13 1313 131313$
13$$131313 1313 13
13amp131313$ 131313
1313 13amp13 131313
Building Science Corporation () wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 1313 13131313 1313 13 13
13 13 1313 13
131313 13131313131313
131313 1313 13 13 1313 13
131313131313 131313
13131313
18 Case 8 Advanced framing with spray foam
13 13 13131313131313
13131313131313 13$
13 $
Figure 44 2x6 wall construction with spray foam insulation
181 Thermal Control
13131313 1313131313 13131313131313
131313131313
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30 Forest St Somerville MA 02143
13amp13 1313$
13amp
0$+ $0
13$
$131313
13131313$1313
13-
Figure 45 Therm modeling of spray foam wall and rim joist
13 amp amp+1+
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amp 131
amp
Table 11 Therm results of spray foam insulation analysis
182 Moisture Control
13 $
1313 13
131313
13
Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313 13 13
13 13 $ 13
131313 23
(+-)$
13 13
1313
13 (+)$
1313 13
1313 3
1313$
1313 13 13
13 1313$
(+) 13 13 1313+-
113 13 13 13
-1313+-$
183 Constructability and Cost
13 13 13 13
$13 13
1313 13 13$
184 Other Considerations
1313
$ 1313
13 1313$
19 Case 9 Hybrid Wall Insulation ndash Flash and Fill
13 $1313
1313 $13
131313$13 131313
13 13$
1313 13 0amp $
13 13
13$ 1313
13 $
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 46 Hybrid wall construction with 2 spray foam and fibrous fill
191 Thermal Control
131313131313
13 1313 13
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131313$(
13 13 13 13
1313
Building Science Corporation amp$ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 47 Therm analysis of hybrid wall system
Table 12 Calculated R-value for a hybrid wall system
192 Moisture Control
+ amp 13
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193 Constructability and Cost
13131313131313
13
1313
194 Other Considerations
1313
1313 1313
1313
Building Science Corporation -+ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 13
13
110 Case 10 Double Stud Wall with Spray Foam
amp 13 13
) 13 13
)13
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131313
13
13 131313
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13
Figure 48 Double stud wall with 2 of spray foam and cellulose fill
1101 Thermal Control
$) 13
13(amp() $
13$
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 49 Therm analysis of double stud wall construction with spray foam
Table 13 Calculated whole wall R-value for a double stud wall system with 2rdquo spray foam
1102 Moisture Control
13 13 (13
13 13
13 1313 13
13 13
($$13(amp$$$13
13 1313 1313 13 13
13 13 13 $13 13
1313 amp+ 13
1313 amp1313 13
13 1313 amp
1313 13 13
1103 Constructability and Cost
13131313 13 13
13131313131313
Building Science Corporation )( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1104 Other Considerations
13 13 13 1313
131313(13 131313 1313 13 amp
13 13 (
131313 1313 13 13 13 13
13 (
111 Case 11 Offset Frame Wall with Exterior Spray Foam
131313 1313 13 1313
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13 1313$ 13 13 13(
13 13 13 13 13 13
$ 13 ( 1313 13 131313131313
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13 13 13 13 13(
1313 ( 1313 13 13
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13 13 13 13 13 13 13 13
(
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 50 Offset frame wall construction with exterior spray foam
1111 Thermal Control
131313 13 1313131313
1313 131313
13 13 13131313
13 13 13 13 13 13 13
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 51 Therm analysis of an offset truss wall with exterior spray foam
Table 14 Calculated whole wall R-value for an offset framed wall with exterior spray foam
1112 Moisture Control
13
$ 13$
+amp13
+amp$
13 131313
1313 ()amp$13
13 13131313
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1313
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1113 Constructability and Cost
13 $13
1313 13 13 $
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($( $$
$ $($$($$+
1114 Other Considerations
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112 Case 12 Exterior Insulation Finish System (EIFS)
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Building Science Corporation 25 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 52 Wall construction using the EIFS cladding system
1121 Thermal Control
1313 1313
1313 1313
1313 131313
13 13 $
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 53 Thermal analysis of an EIFS wall system
Table 15 Calculated whole wall R-value for a EIFS wall system with 4rdquo of EPS
1122 Moisture Control
1313131313131313
131313amp1313
13131313
131313amp
13131313131313
13 13 13+ 13amp 131313
1313131313 131313) amp
1123 Constructability and Cost
131313131313
131313amp1313131313amp
131313131313 1313 13
1313amp
1124 Other Considerations
131313131313amp 13
13131313 131313
13amp13$1313131313
1313131313amp 131313131313
131313131313amp
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
D Conclusions
amp 1313
)- 13$13
13131313 1313
1313
Table 16 Summary of all calculated R-values
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30 Forest St Somerville MA 02143
Table 17 Hours of potential winter time air leakage condensation
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30 Forest St Somerville MA 02143
Table 18 Wall Comparison Chart
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30 Forest St Somerville MA 02143
E Works Cited
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30 Forest St Somerville MA 02143
Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
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A Introduction
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
2 SCOPE
$$amp$ ($$$ $amp$amp$$ amp amp $$
$ amp $amp$amp$ $ amp $ $
$$ $ $amp$ $$ $amp
amp $ampamp amp$ $$ ( + $
3 APPROACH
$$amp)$ $amp ampamp $amp$
amp$$ ($$$$ ( $ $$ (
$ $amp2 3 $
($amp$$$ $ amp$
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B Analysis
1 WALL ASSEMBLIES REVIEWED
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bull $5- $amp 13(6)8
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bull $-ampamp$amp13$$213$3
bull $-$amp $2$3
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2 ANALYSIS CRITERIA
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Building Science Corporation 6 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 1 Criteria comparison matrix
1313 13amp13 13 13
1313 13 1313 13 13
13 1313 13 131313 1313
131313 )13 13 130) 13
13 131313 13$13
13 $
131313 $ 13 131313 13 13
13amp13 131313$13amp $13
13 13 13amp1313 13 1313$ 13
)+01313$ 13 )-+1313amp 13
131313 13 13
21 Heat flow analysis
1313 131313 13 130-amp13 (13
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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Figure 1 Plan view of wall section for Therm simulation
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Building Science Corporation - wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 2 Top plate simulation with 8rdquo of wall
131313
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Figure 3 Rim joist simulation with 8 of wall
13
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Figure 4 Plan section of rim joist floor joists and fiberglass batt insulation
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313 131313 1313131313 131313
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13 13
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13 13 1313131313131313
1313131313$131313 1313
13131313 13131313131313
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Figure 5 Common Convective Heat Flow Paths in Enclosures
131313 131313131313 131313
1313131313131313 13131313
131313131313 13131313
Building Science Corporation ) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
(
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Table 2 Conductivity values used for two dimensional heat flow analysis
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Building Science Corporation 6 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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30 Forest St Somerville MA 02143
Table 3 R-values for analyzed wall systems
22 Hygrothermal Analysis
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Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
222 Wintertime Condensation
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Building Science Corporation 11 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 9 Winter time sheathing relative humidity for Case 1 and Case 2
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30 Forest St Somerville MA 02143
Figure 10 Winter air leakage condensation potential for Case 1 and Case 2
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30 Forest St Somerville MA 02143
Figure 11 Winter air leakage condensation potential for Case 1 and Case 9
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 14 Winter air leakage condensation potential for Case 4 and Case 10
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 15 Installation of high density spray foam in an Offset Framed Wall in a cold climate
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 16 Winter time air leakage condensation potential for Case 5 and Case 11
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30 Forest St Somerville MA 02143
Figure 17 Winter time sheathing relative humidity for Case 8
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Building Science Corporation - wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 18 Winter air leakage condensation potential for Case 8
223 Summer Inward Vapor Drives
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Building Science Corporation -+ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 19 Inward vapor drive relative humidity of poly or GWB for Case 1 Case 2 and Case 9
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 22 Inward vapor drive relative humidity of poly or GWB for Case 8
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30 Forest St Somerville MA 02143
Figure 23 Inward vapor drive relative humidity of poly or GWB for Cases 5 8 and 11
224 Wall Drying
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Building Science Corporation 02 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 24 Drying Curves for Case 1 and Case 2
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 26 Drying curves for Case 8
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Figure 27 Drying Curves for Case 4 and Case 10 with and without a poly vapor barrier
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Building Science Corporation 30 Forest St Somerville MA 02143
(+ wwwbuildingsciencecom
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Figure 28 Drying Curves for Case 5 and Case 11
23 Enclosure Durability
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24 Buildability
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
25 Material Use
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26 Cost
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Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 29 Standard construction practice
111 Thermal Control
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Building Science Corporation - wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 30 Therm modeling of Case 1 - 2x6 construction
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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Building Science Corporation 0 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 31 Advanced framing construction
121 Thermal Control
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Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 32 Therm modeling of Case 2 advanced framing with 1 XPS insulated sheathing
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122 Moisture Control
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Building Science Corporation 00 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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124 Other Considerations
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 33 2x6 wall construction with interior strapping
131 Thermal Control
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 34 Therm analysis of horizontally strapped wall
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Table 7 Calculated R-value of an interior horizontal strapped wall
132 Moisture Control
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30 Forest St Somerville MA 02143
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134 Other Considerations
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Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 35 Double stud wall
141 Thermal Control
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30 Forest St Somerville MA 02143
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Table 8 Calculated R-value of a double stud wall
142 Moisture Control
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30 Forest St Somerville MA 02143
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143 Constructability and Cost
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144 Other Considerations
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Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 37 Truss wall construction
151 Thermal Control
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 38 Therm results of the truss wall
Table 9 Calculated R-value for truss wall
152 Moisture Control
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30 Forest St Somerville MA 02143
153 Constructability and Cost
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154 Other Considerations
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Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
161 Thermal Control
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Table 10 Calculated R-value for a Sips wall system
162 Moisture Control
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Building Science Corporation 33 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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17 Case 7 Insulated Concrete Forms (ICFs)
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 41 ICF wall construction
171 Thermal Control
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Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 42 Nine inch foam ICF with five inches of EPS
Figure 43 Fifteen inch foam ICF with five inches of EPS
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172 Moisture Control
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173 Constructability and Cost
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174 Other Considerations
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Building Science Corporation () wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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18 Case 8 Advanced framing with spray foam
13 13 13131313131313
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Figure 44 2x6 wall construction with spray foam insulation
181 Thermal Control
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Building Science Corporation amp( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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182 Moisture Control
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Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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183 Constructability and Cost
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184 Other Considerations
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 46 Hybrid wall construction with 2 spray foam and fibrous fill
191 Thermal Control
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30 Forest St Somerville MA 02143
Figure 47 Therm analysis of hybrid wall system
Table 12 Calculated R-value for a hybrid wall system
192 Moisture Control
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193 Constructability and Cost
13131313131313
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Building Science Corporation -+ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 13
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110 Case 10 Double Stud Wall with Spray Foam
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Figure 48 Double stud wall with 2 of spray foam and cellulose fill
1101 Thermal Control
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Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 49 Therm analysis of double stud wall construction with spray foam
Table 13 Calculated whole wall R-value for a double stud wall system with 2rdquo spray foam
1102 Moisture Control
13 13 (13
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13131313 13 13
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30 Forest St Somerville MA 02143
1104 Other Considerations
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111 Case 11 Offset Frame Wall with Exterior Spray Foam
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 50 Offset frame wall construction with exterior spray foam
1111 Thermal Control
131313 13 1313131313
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13 13 13 13 13 13 13
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 51 Therm analysis of an offset truss wall with exterior spray foam
Table 14 Calculated whole wall R-value for an offset framed wall with exterior spray foam
1112 Moisture Control
13
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13 131313
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30 Forest St Somerville MA 02143
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Building Science Corporation 25 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 52 Wall construction using the EIFS cladding system
1121 Thermal Control
1313 1313
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Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 53 Thermal analysis of an EIFS wall system
Table 15 Calculated whole wall R-value for a EIFS wall system with 4rdquo of EPS
1122 Moisture Control
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1123 Constructability and Cost
131313131313
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Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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Table 16 Summary of all calculated R-values
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Building Science Corporation -) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 17 Hours of potential winter time air leakage condensation
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Building Science Corporation (amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 18 Wall Comparison Chart
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$13$1313$ 13$
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30 Forest St Somerville MA 02143
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30 Forest St Somerville MA 02143
E Works Cited
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Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
A Introduction
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2 SCOPE
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3 APPROACH
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B Analysis
1 WALL ASSEMBLIES REVIEWED
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2 ANALYSIS CRITERIA
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30 Forest St Somerville MA 02143
Table 1 Criteria comparison matrix
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21 Heat flow analysis
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Figure 1 Plan view of wall section for Therm simulation
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30 Forest St Somerville MA 02143
Figure 2 Top plate simulation with 8rdquo of wall
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Figure 4 Plan section of rim joist floor joists and fiberglass batt insulation
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30 Forest St Somerville MA 02143
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Figure 5 Common Convective Heat Flow Paths in Enclosures
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30 Forest St Somerville MA 02143
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Table 2 Conductivity values used for two dimensional heat flow analysis
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Building Science Corporation 6 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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Figure 6 Typical framing 16oc - 9 framing factor
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Figure 7 Actual average framing factor of 23 in standard construction
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Building Science Corporation 2 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 3 R-values for analyzed wall systems
22 Hygrothermal Analysis
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30 Forest St Somerville MA 02143
13
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221 Moisture Balance
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Figure 8 Moisture balance
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
222 Wintertime Condensation
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Table 4 Vapor control strategies and permeance values for Case 1 and 2
Building Science Corporation 11 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 9 Winter time sheathing relative humidity for Case 1 and Case 2
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30 Forest St Somerville MA 02143
Figure 10 Winter air leakage condensation potential for Case 1 and Case 2
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30 Forest St Somerville MA 02143
Figure 11 Winter air leakage condensation potential for Case 1 and Case 9
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Figure 12 Winter time sheathing relative humidity for Case 3 Case 4 and Case 5
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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30 Forest St Somerville MA 02143
Figure 14 Winter air leakage condensation potential for Case 4 and Case 10
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 15 Installation of high density spray foam in an Offset Framed Wall in a cold climate
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 16 Winter time air leakage condensation potential for Case 5 and Case 11
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30 Forest St Somerville MA 02143
Figure 17 Winter time sheathing relative humidity for Case 8
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Building Science Corporation - wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 18 Winter air leakage condensation potential for Case 8
223 Summer Inward Vapor Drives
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Building Science Corporation -+ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 19 Inward vapor drive relative humidity of poly or GWB for Case 1 Case 2 and Case 9
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Figure 20 Inward vapor drive relative humidity of poly or GWB for Case 3 Case 4 and Case 5
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 22 Inward vapor drive relative humidity of poly or GWB for Case 8
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Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 23 Inward vapor drive relative humidity of poly or GWB for Cases 5 8 and 11
224 Wall Drying
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Building Science Corporation 02 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 24 Drying Curves for Case 1 and Case 2
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Figure 25 Drying curves for Case 3 Case 4 and Case 5
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 26 Drying curves for Case 8
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Figure 27 Drying Curves for Case 4 and Case 10 with and without a poly vapor barrier
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Building Science Corporation 30 Forest St Somerville MA 02143
(+ wwwbuildingsciencecom
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23 Enclosure Durability
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
25 Material Use
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26 Cost
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1 CASE 1 STANDARD CONSTRUCTION PRACTICE
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Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 29 Standard construction practice
111 Thermal Control
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Building Science Corporation - wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 30 Therm modeling of Case 1 - 2x6 construction
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112 Moisture Control
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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Building Science Corporation 0 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 31 Advanced framing construction
121 Thermal Control
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Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 32 Therm modeling of Case 2 advanced framing with 1 XPS insulated sheathing
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Table 6 Summary of R-value results from Therm modeling for Case 2
122 Moisture Control
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Building Science Corporation 00 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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124 Other Considerations
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13 Case 3 Interior 2x3 horizontal strapping
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 33 2x6 wall construction with interior strapping
131 Thermal Control
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 34 Therm analysis of horizontally strapped wall
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Table 7 Calculated R-value of an interior horizontal strapped wall
132 Moisture Control
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Building Science Corporation 1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 35 Double stud wall
141 Thermal Control
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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Table 8 Calculated R-value of a double stud wall
142 Moisture Control
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Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 37 Truss wall construction
151 Thermal Control
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 38 Therm results of the truss wall
Table 9 Calculated R-value for truss wall
152 Moisture Control
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30 Forest St Somerville MA 02143
153 Constructability and Cost
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154 Other Considerations
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16 Case 6 Structural Insulated Panel Systems (SIPs)
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Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
161 Thermal Control
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Table 10 Calculated R-value for a Sips wall system
162 Moisture Control
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Building Science Corporation 33 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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17 Case 7 Insulated Concrete Forms (ICFs)
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 41 ICF wall construction
171 Thermal Control
1313
1313 1313
131313 (
+$)$13 13($
amp)$)
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 42 Nine inch foam ICF with five inches of EPS
Figure 43 Fifteen inch foam ICF with five inches of EPS
13 13 1313
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172 Moisture Control
1313131313131313 13$amp131313
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$ 13$1313$13ampamp
13 1313$1313131313
131313amp13
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173 Constructability and Cost
13131313 $1313$13$ 13
13 13$1313amp13$13
1313 amp13 13
13 13 1313$
13$13 13$131313
131313 1313 13$amp
174 Other Considerations
13 1313 131313$
13$$131313 1313 13
13amp131313$ 131313
1313 13amp13 131313
Building Science Corporation () wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 1313 13131313 1313 13 13
13 13 1313 13
131313 13131313131313
131313 1313 13 13 1313 13
131313131313 131313
13131313
18 Case 8 Advanced framing with spray foam
13 13 13131313131313
13131313131313 13$
13 $
Figure 44 2x6 wall construction with spray foam insulation
181 Thermal Control
13131313 1313131313 13131313131313
131313131313
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30 Forest St Somerville MA 02143
13amp13 1313$
13amp
0$+ $0
13$
$131313
13131313$1313
13-
Figure 45 Therm modeling of spray foam wall and rim joist
13 amp amp+1+
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13-amp(1+)13
amp 131
amp
Table 11 Therm results of spray foam insulation analysis
182 Moisture Control
13 $
1313 13
131313
13
Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313 13 13
13 13 $ 13
131313 23
(+-)$
13 13
1313
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1313 13
1313 3
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1313 13 13
13 1313$
(+) 13 13 1313+-
113 13 13 13
-1313+-$
183 Constructability and Cost
13 13 13 13
$13 13
1313 13 13$
184 Other Considerations
1313
$ 1313
13 1313$
19 Case 9 Hybrid Wall Insulation ndash Flash and Fill
13 $1313
1313 $13
131313$13 131313
13 13$
1313 13 0amp $
13 13
13$ 1313
13 $
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 46 Hybrid wall construction with 2 spray foam and fibrous fill
191 Thermal Control
131313131313
13 1313 13
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131313$(
13 13 13 13
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30 Forest St Somerville MA 02143
Figure 47 Therm analysis of hybrid wall system
Table 12 Calculated R-value for a hybrid wall system
192 Moisture Control
+ amp 13
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193 Constructability and Cost
13131313131313
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194 Other Considerations
1313
1313 1313
1313
Building Science Corporation -+ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 13
13
110 Case 10 Double Stud Wall with Spray Foam
amp 13 13
) 13 13
)13
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131313
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13
Figure 48 Double stud wall with 2 of spray foam and cellulose fill
1101 Thermal Control
$) 13
13(amp() $
13$
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 49 Therm analysis of double stud wall construction with spray foam
Table 13 Calculated whole wall R-value for a double stud wall system with 2rdquo spray foam
1102 Moisture Control
13 13 (13
13 13
13 1313 13
13 13
($$13(amp$$$13
13 1313 1313 13 13
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1313 amp+ 13
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1313 13 13
1103 Constructability and Cost
13131313 13 13
13131313131313
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30 Forest St Somerville MA 02143
1104 Other Considerations
13 13 13 1313
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111 Case 11 Offset Frame Wall with Exterior Spray Foam
131313 1313 13 1313
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13 13 13 13 13 13
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 50 Offset frame wall construction with exterior spray foam
1111 Thermal Control
131313 13 1313131313
1313 131313
13 13 13131313
13 13 13 13 13 13 13
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 51 Therm analysis of an offset truss wall with exterior spray foam
Table 14 Calculated whole wall R-value for an offset framed wall with exterior spray foam
1112 Moisture Control
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30 Forest St Somerville MA 02143
$($( $$
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1114 Other Considerations
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112 Case 12 Exterior Insulation Finish System (EIFS)
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Building Science Corporation 25 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 52 Wall construction using the EIFS cladding system
1121 Thermal Control
1313 1313
1313 1313
1313 131313
13 13 $
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 53 Thermal analysis of an EIFS wall system
Table 15 Calculated whole wall R-value for a EIFS wall system with 4rdquo of EPS
1122 Moisture Control
1313131313131313
131313amp1313
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13131313131313
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1313131313 131313) amp
1123 Constructability and Cost
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1313amp
1124 Other Considerations
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1313131313amp 131313131313
131313131313amp
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30 Forest St Somerville MA 02143
D Conclusions
amp 1313
)- 13$13
13131313 1313
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Table 16 Summary of all calculated R-values
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30 Forest St Somerville MA 02143
Table 17 Hours of potential winter time air leakage condensation
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30 Forest St Somerville MA 02143
Table 18 Wall Comparison Chart
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30 Forest St Somerville MA 02143
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30 Forest St Somerville MA 02143
E Works Cited
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30 Forest St Somerville MA 02143
Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
2 SCOPE
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$ amp $amp$amp$ $ amp $ $
$$ $ $amp$ $$ $amp
amp $ampamp amp$ $$ ( + $
3 APPROACH
$$amp)$ $amp ampamp $amp$
amp$$ ($$$$ ( $ $$ (
$ $amp2 3 $
($amp$$$ $ amp$
(((amp$amp $ $amp0$ $amp$
$ $$ $ $amp $$
B Analysis
1 WALL ASSEMBLIES REVIEWED
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bull $5- $amp 13(6)
bull $5- $amp 13(6)8
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bull $7- 6)7 + $
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bull $-ampamp$amp13$$213$3
bull $-$amp $2$3
bull $lt-( ($2493$
bull $lt-($2643$
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bull $54- ampamp((61 $2643$ amp$$amp
bull $55-) $26432$3$ ( amp$$amp
bull $56-) $amp $$2 3
2 ANALYSIS CRITERIA
$ )(amp$ amp ($$$$
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5$)
Building Science Corporation 6 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 1 Criteria comparison matrix
1313 13amp13 13 13
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131313 $ 13 131313 13 13
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13 13 13amp1313 13 1313$ 13
)+01313$ 13 )-+1313amp 13
131313 13 13
21 Heat flow analysis
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30 Forest St Somerville MA 02143
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Figure 1 Plan view of wall section for Therm simulation
13
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Building Science Corporation - wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 2 Top plate simulation with 8rdquo of wall
131313
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Figure 3 Rim joist simulation with 8 of wall
13
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Figure 4 Plan section of rim joist floor joists and fiberglass batt insulation
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313 131313 1313131313 131313
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$13+$1313 131313 13$13 13
13 13
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13 13 1313131313131313
1313131313$131313 1313
13131313 13131313131313
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Figure 5 Common Convective Heat Flow Paths in Enclosures
131313 131313131313 131313
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131313131313 13131313
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30 Forest St Somerville MA 02143
(
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amp $)
amp amp amp(
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ampamp amp (
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Table 2 Conductivity values used for two dimensional heat flow analysis
$ $ amp (
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Building Science Corporation 6 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
131313341313131313
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Figure 6 Typical framing 16oc - 9 framing factor
13 13131313 131313$+013$$
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Figure 7 Actual average framing factor of 23 in standard construction
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1313131341313 131313+041313
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Building Science Corporation 2 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 3 R-values for analyzed wall systems
22 Hygrothermal Analysis
ampampamp ampamp amp( ) ampamp3
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13
amp
221 Moisture Balance
13 amp
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Figure 8 Moisture balance
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
222 Wintertime Condensation
13 +
( $
+ $
$ 30 amp
60 + $ $
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30 +amp $ +
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+
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1 57+4-middot2middot
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$ 5)6)7)8 4
1102+5+ )$ )$
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9 $$ 1)
)2)$ +$
1)$ 21
)amp 24 +4
$ $ 9+
Table 4 Vapor control strategies and permeance values for Case 1 and 2
Building Science Corporation 11 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 9 Winter time sheathing relative humidity for Case 1 and Case 2
13 + - 13
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Building Science Corporation - wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 10 Winter air leakage condensation potential for Case 1 and Case 2
$
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 11 Winter air leakage condensation potential for Case 1 and Case 9
13 $1313
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Figure 12 Winter time sheathing relative humidity for Case 3 Case 4 and Case 5
13$13 13
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
131313amp13 13 13$
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Figure 13 Winter air leakage condensation potential for Case 3 Case 4 and Case 5
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Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 14 Winter air leakage condensation potential for Case 4 and Case 10
13
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 15 Installation of high density spray foam in an Offset Framed Wall in a cold climate
13
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 16 Winter time air leakage condensation potential for Case 5 and Case 11
13 $$
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Building Science Corporation +- wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 17 Winter time sheathing relative humidity for Case 8
13131313 13 131313
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13 131313amp)1313131313
13131313131313 13 13131313
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13131313 13131313 13
131313131313131313
13131313131313 13
Building Science Corporation - wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 18 Winter air leakage condensation potential for Case 8
223 Summer Inward Vapor Drives
13 13 131313
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1313 1313$13 13$13131313$
1313 13 $13
13131313
1313
13 13 131313 131313
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13131313 13 1313$1313
1313 1313$1313
11313$1313$13-$13 131313
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1313131313 13131313$
13 131313 131313amp
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13((-131313$13 1313
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Building Science Corporation -+ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 19 Inward vapor drive relative humidity of poly or GWB for Case 1 Case 2 and Case 9
13$13 131313
1313 131313 13
1313$1313 13
13131313131313
Figure 20 Inward vapor drive relative humidity of poly or GWB for Case 3 Case 4 and Case 5
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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Figure 21 Inward vapor drive relative humidity of poly or GWB for Case 4 and Case 10
1313
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 22 Inward vapor drive relative humidity of poly or GWB for Case 8
() 13
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Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 23 Inward vapor drive relative humidity of poly or GWB for Cases 5 8 and 11
224 Wall Drying
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Building Science Corporation 02 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 24 Drying Curves for Case 1 and Case 2
13131313 13 13
13 131313
Figure 25 Drying curves for Case 3 Case 4 and Case 5
13 1313
13131313131313
131313 13
13
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 26 Drying curves for Case 8
1313 1313$13)1313
1313$ 13amp 13)1313 13amp13 13 1313
13(13131313 13)13 13 13
13131313131313131313131313 13
1313131313 13131313 131313
131313131313131313131313131313 13
Figure 27 Drying Curves for Case 4 and Case 10 with and without a poly vapor barrier
131313131313 1313 131313
131313 13131313 13 13
Building Science Corporation 30 Forest St Somerville MA 02143
(+ wwwbuildingsciencecom
13 1313
1313 131313
$$ 1313
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Figure 28 Drying Curves for Case 5 and Case 11
23 Enclosure Durability
13 13 13
131313
13 131313
13 13 13 1313
13131313 13
1313
1313
24 Buildability
13 1313
13131313 13
1313 13 13131313
1313
13
1313 131313
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
25 Material Use
13131313 1313
13131313$131313
13 1313131313131313131313
13131313131313$1313131313
1313131313
131313$
26 Cost
13 131313131313
1313$1313131313
13131313 1313
13$13amp1313 213
1313 )+$1313 13)-$+
1313$13131313 1313131313
131313$
C Results
1 CASE 1 STANDARD CONSTRUCTION PRACTICE
131313131313--0130(13
13131301313131313133 13$)-2
131313 13131313$
Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 29 Standard construction practice
111 Thermal Control
13) amp( 13
+amp-
13 13 ( ampampampamp(amp13$
13 $ 13 13
13 13
13(
Building Science Corporation - wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 30 Therm modeling of Case 1 - 2x6 construction
1313 13 13 131313 (-$13
13 131313 1313 13
131313) )13131313131313(-131313
13131313131313131313
13 13131313131313131313)+
13)-13131313131313 13
13
Table 5 Summary of R-value results from Therm modeling for Case 1
1313131313131313131313
131313 131313 13 13
13 1313131313
1313 1313 131313
13 13 13 13
112 Moisture Control
1313131313 13131313 13
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
131313
amp 13
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113 Constructability and Cost
13
amp13
13amp
114 Other Considerations
13
13amp
131+13
amp 13
13amp
12 Case 2 Advanced framing with insulated sheathing
1313
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amp 3131(ampamp
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13amp13
13 13
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13amp
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Building Science Corporation 0 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 31 Advanced framing construction
121 Thermal Control
131313 13$13 1313
1313 13$13$1313 13
$$)amp $$)13$$13 13) 13
1313131313 1313
131313(-(13$amp-( 1313amp
+(13$13$1313$1313amp13
1313131313 1313
131313 1313
13131313131313
131313amp1313 13
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 32 Therm modeling of Case 2 advanced framing with 1 XPS insulated sheathing
amp $ $ 13 + 2 3$$35
$) 3( -(3 1(2($
$ amp 2($ )
$ ($ $
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3(2 213 (
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Table 6 Summary of R-value results from Therm modeling for Case 2
122 Moisture Control
$
$$$
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$ (-(2( $
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$
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(13
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Building Science Corporation 00 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
131313$ 1313
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13 1313 13
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131313 $ )
2 131313
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123 Constructability and Cost
131313131313
13130$
13-$131313
131313(13
$$13131313
13 1313
124 Other Considerations
amp 1313
1313
1313$ 13 13
131313$1313 13
1313
13 Case 3 Interior 2x3 horizontal strapping
13 $
13$
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 33 2x6 wall construction with interior strapping
131 Thermal Control
1313 1313131313
1313131313 amp
1313131313 1313
131313 13 13131313
1313 1313131313
1313 1313 1313131313
13131313 13
13 13131313$
131313 13
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 34 Therm analysis of horizontally strapped wall
13$13-amp0)132amp 13$
3-1 1amp13 13
amp 13 13amp
Table 7 Calculated R-value of an interior horizontal strapped wall
132 Moisture Control
13
(1313$amp
$ 13)
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$amp
13$ 13$
13 $amp
$
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$ $ 13
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Building Science Corporation 1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 13
133 Constructability and Cost
1313$
13 13
1313
134 Other Considerations
13
131313
13
14 Case 4 Double Stud
1313
131313
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 35 Double stud wall
141 Thermal Control
13
1313) 13
)13
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13 13
1313
1313
13
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13 13
$ 13
1313
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13$131313
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)-0 13 13
amp13 1313$
13amp$1amp(13 13
-amp $
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Figure 36 Therm model of the double stud wall
Table 8 Calculated R-value of a double stud wall
142 Moisture Control
13131313
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131313$13
131313
13amp 0++ 13$-
1313$
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Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13
13)amp 13
13 1313
13
13
13(13$)- 13)amp
143 Constructability and Cost
13
amp 13
144 Other Considerations
13 13
131313
13 1313
15 Case 5 Truss Wall
1313
13 13131313
13 13 13
131313amp
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 37 Truss wall construction
151 Thermal Control
1313
13 13(
1313)1313
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amp
13
1313
)-13
131313
13
13 $)
13 13
13131313
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 38 Therm results of the truss wall
Table 9 Calculated R-value for truss wall
152 Moisture Control
13
1313
13 1313
13amp(
131313
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1313
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13
13
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13
13
1313
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Building Science Corporation amp$ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
153 Constructability and Cost
13
13131313
13
13+($13
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$ 13
154 Other Considerations
13 $$
1313amp
)
16 Case 6 Structural Insulated Panel Systems (SIPs)
131313
13 13$13 13
amp
Figure 39 SIPs wall construction
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
161 Thermal Control
13 13
-)2)4+(4)4+(6)4+) 13
)13 $$
$2)6)
13 $ (
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)
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27( $ amp03)4 13
)$ amp02)5
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Figure 40 Therm results of SIPs panel analysis
Table 10 Calculated R-value for a Sips wall system
162 Moisture Control
13 $ $ amp
$ ) ( 13
amp
-1311) 13 $
)
Building Science Corporation 33 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($$
amp$$+$($
163 Constructability and Cost
$amp $$$$ $
()$$(($(
+amp
164 Other Considerations
()($$$((
$) $ $$
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17 Case 7 Insulated Concrete Forms (ICFs)
(amp($
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 41 ICF wall construction
171 Thermal Control
1313
1313 1313
131313 (
+$)$13 13($
amp)$)
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 42 Nine inch foam ICF with five inches of EPS
Figure 43 Fifteen inch foam ICF with five inches of EPS
13 13 1313
13 1313131313$13$1313
1313amp1313 13 1313
13131313$amp
172 Moisture Control
1313131313131313 13$amp131313
131313 13amp13
$ 13$1313$13ampamp
13 1313$1313131313
131313amp13
1313131313 13amp
173 Constructability and Cost
13131313 $1313$13$ 13
13 13$1313amp13$13
1313 amp13 13
13 13 1313$
13$13 13$131313
131313 1313 13$amp
174 Other Considerations
13 1313 131313$
13$$131313 1313 13
13amp131313$ 131313
1313 13amp13 131313
Building Science Corporation () wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 1313 13131313 1313 13 13
13 13 1313 13
131313 13131313131313
131313 1313 13 13 1313 13
131313131313 131313
13131313
18 Case 8 Advanced framing with spray foam
13 13 13131313131313
13131313131313 13$
13 $
Figure 44 2x6 wall construction with spray foam insulation
181 Thermal Control
13131313 1313131313 13131313131313
131313131313
Building Science Corporation amp( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13amp13 1313$
13amp
0$+ $0
13$
$131313
13131313$1313
13-
Figure 45 Therm modeling of spray foam wall and rim joist
13 amp amp+1+
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13-amp(1+)13
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amp
Table 11 Therm results of spray foam insulation analysis
182 Moisture Control
13 $
1313 13
131313
13
Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313 13 13
13 13 $ 13
131313 23
(+-)$
13 13
1313
13 (+)$
1313 13
1313 3
1313$
1313 13 13
13 1313$
(+) 13 13 1313+-
113 13 13 13
-1313+-$
183 Constructability and Cost
13 13 13 13
$13 13
1313 13 13$
184 Other Considerations
1313
$ 1313
13 1313$
19 Case 9 Hybrid Wall Insulation ndash Flash and Fill
13 $1313
1313 $13
131313$13 131313
13 13$
1313 13 0amp $
13 13
13$ 1313
13 $
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 46 Hybrid wall construction with 2 spray foam and fibrous fill
191 Thermal Control
131313131313
13 1313 13
$amp $ amp 13
131313$(
13 13 13 13
1313
Building Science Corporation amp$ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 47 Therm analysis of hybrid wall system
Table 12 Calculated R-value for a hybrid wall system
192 Moisture Control
+ amp 13
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13
13 +(
131313
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193 Constructability and Cost
13131313131313
13
1313
194 Other Considerations
1313
1313 1313
1313
Building Science Corporation -+ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 13
13
110 Case 10 Double Stud Wall with Spray Foam
amp 13 13
) 13 13
)13
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131313
13
13 131313
1313 13 1313 13
13
Figure 48 Double stud wall with 2 of spray foam and cellulose fill
1101 Thermal Control
$) 13
13(amp() $
13$
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 49 Therm analysis of double stud wall construction with spray foam
Table 13 Calculated whole wall R-value for a double stud wall system with 2rdquo spray foam
1102 Moisture Control
13 13 (13
13 13
13 1313 13
13 13
($$13(amp$$$13
13 1313 1313 13 13
13 13 13 $13 13
1313 amp+ 13
1313 amp1313 13
13 1313 amp
1313 13 13
1103 Constructability and Cost
13131313 13 13
13131313131313
Building Science Corporation )( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1104 Other Considerations
13 13 13 1313
131313(13 131313 1313 13 amp
13 13 (
131313 1313 13 13 13 13
13 (
111 Case 11 Offset Frame Wall with Exterior Spray Foam
131313 1313 13 1313
13 13 13 13( 13 1313131313 131313
13 1313$ 13 13 13(
13 13 13 13 13 13
$ 13 ( 1313 13 131313131313
1313 13 13( 1313
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13 13 13 13 13(
1313 ( 1313 13 13
1313 (1313 13 13 13 1313
1313 13 13( 1313
13 13 13$13 -++13 13
131313 1313 1313(13 13
13 13 13 )13
13 13 13 13 13 13 13 13
(
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 50 Offset frame wall construction with exterior spray foam
1111 Thermal Control
131313 13 1313131313
1313 131313
13 13 13131313
13 13 13 13 13 13 13
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 51 Therm analysis of an offset truss wall with exterior spray foam
Table 14 Calculated whole wall R-value for an offset framed wall with exterior spray foam
1112 Moisture Control
13
$ 13$
+amp13
+amp$
13 131313
1313 ()amp$13
13 13131313
1313$
1313
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1113 Constructability and Cost
13 $13
1313 13 13 $
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($( $$
$ $($$($$+
1114 Other Considerations
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112 Case 12 Exterior Insulation Finish System (EIFS)
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Building Science Corporation 25 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 52 Wall construction using the EIFS cladding system
1121 Thermal Control
1313 1313
1313 1313
1313 131313
13 13 $
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 53 Thermal analysis of an EIFS wall system
Table 15 Calculated whole wall R-value for a EIFS wall system with 4rdquo of EPS
1122 Moisture Control
1313131313131313
131313amp1313
13131313
131313amp
13131313131313
13 13 13+ 13amp 131313
1313131313 131313) amp
1123 Constructability and Cost
131313131313
131313amp1313131313amp
131313131313 1313 13
1313amp
1124 Other Considerations
131313131313amp 13
13131313 131313
13amp13$1313131313
1313131313amp 131313131313
131313131313amp
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
D Conclusions
amp 1313
)- 13$13
13131313 1313
1313
Table 16 Summary of all calculated R-values
131313 amp
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amp+( 1313
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1313131313 13
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) 13
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Building Science Corporation -) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 17 Hours of potential winter time air leakage condensation
13
) 1313amp$13
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amp13amp$13
131313
13
1313
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1313
Building Science Corporation (amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 18 Wall Comparison Chart
$$ 13$$13
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13 13 amp
$13$1313$ 13$
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$ $13$ amp13 $13
13
13 $amp13
13$13 13
$ $ 13amp
amp
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30 Forest St Somerville MA 02143
1313
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13 1313
13
131313 1313
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30 Forest St Somerville MA 02143
E Works Cited
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Building Science Corporation GF wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
Table 1 Criteria comparison matrix
1313 13amp13 13 13
1313 13 1313 13 13
13 1313 13 131313 1313
131313 )13 13 130) 13
13 131313 13$13
13 $
131313 $ 13 131313 13 13
13amp13 131313$13amp $13
13 13 13amp1313 13 1313$ 13
)+01313$ 13 )-+1313amp 13
131313 13 13
21 Heat flow analysis
1313 131313 13 130-amp13 (13
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131313 1313 131313
13 13
1313amp 1313 13 1313 1313 13-$ 1313 13
13 13 13 13 1313 amp
13 13 13 1313 13 13 13 13 (
1313 13 1313 1313(13 13
amp131313 13 )
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13
amp 13 13 $amp
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amp
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13 13$amp
13
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$$ 13$ amp
13131313
13$$ $
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$ ()((
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13$ 13
$amp
$amp $
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$
13amp
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$ 13
$amp amp
Figure 1 Plan view of wall section for Therm simulation
13
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Building Science Corporation - wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 2 Top plate simulation with 8rdquo of wall
131313
1313
131313
1313131313
1313
Figure 3 Rim joist simulation with 8 of wall
13
1313
amp$ 131313
Figure 4 Plan section of rim joist floor joists and fiberglass batt insulation
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313 131313 1313131313 131313
1313131313131313
13amp
1313$131313131313 131313 $1313
131313131313 131313 1313
1313131313131313
$13+$1313 131313 13$13 13
13 13
$13 13 13 13
13 13 1313131313131313
1313131313$131313 1313
13131313 13131313131313
13(
Figure 5 Common Convective Heat Flow Paths in Enclosures
131313 131313131313 131313
1313131313131313 13131313
131313131313 13131313
Building Science Corporation ) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
(
amp ) (
) 13
amp
) ( $amp
$ amp$ amp
( $ amp
(
$ $
amp$ $ ( $
(
$amp $
(
13
amp $)
amp amp amp(
amp amp (
amp $$18-578
)18-)38 ( ) $
ampamp amp (
$
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13 $ (
7(21 23(1 $
Table 2 Conductivity values used for two dimensional heat flow analysis
$ $ amp (
amp +$ )
(13 amp$ amp
-34( $$ 05 ((-5
Building Science Corporation 6 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
131313341313131313
1313$1313$$
Figure 6 Typical framing 16oc - 9 framing factor
13 13131313 131313$+013$$
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13+-131313+0++1313413
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131313 13131313 13131313+-
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amp 13
Figure 7 Actual average framing factor of 23 in standard construction
1313131313 1313(1313
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1313 131313$13131313 131313
1313+0413$1313131313
1313131341313 131313+041313
13-1313amp 131313 13 1313
1313
Building Science Corporation 2 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 3 R-values for analyzed wall systems
22 Hygrothermal Analysis
ampampamp ampamp amp( ) ampamp3
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13
amp
221 Moisture Balance
13 amp
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13
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13
1313
13
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0+ 1313
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13
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Figure 8 Moisture balance
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
222 Wintertime Condensation
13 +
( $
+ $
$ 30 amp
60 + $ $
$ +) $ 20
30 +amp $ +
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9 $$ 1)
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1)$ 21
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$ $ 9+
Table 4 Vapor control strategies and permeance values for Case 1 and 2
Building Science Corporation 11 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 9 Winter time sheathing relative humidity for Case 1 and Case 2
13 + - 13
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Building Science Corporation - wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 10 Winter air leakage condensation potential for Case 1 and Case 2
$
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 11 Winter air leakage condensation potential for Case 1 and Case 9
13 $1313
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Figure 12 Winter time sheathing relative humidity for Case 3 Case 4 and Case 5
13$13 13
13
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
131313amp13 13 13$
131313
Figure 13 Winter air leakage condensation potential for Case 3 Case 4 and Case 5
1313 131313$1313$13
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13131313 131313
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13$1313$ 1313131313$
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Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 14 Winter air leakage condensation potential for Case 4 and Case 10
13
13131313
1313$
1313131313
13
131313 131313
13amp
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13 1313
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 15 Installation of high density spray foam in an Offset Framed Wall in a cold climate
13
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 16 Winter time air leakage condensation potential for Case 5 and Case 11
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30 Forest St Somerville MA 02143
Figure 17 Winter time sheathing relative humidity for Case 8
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30 Forest St Somerville MA 02143
Figure 18 Winter air leakage condensation potential for Case 8
223 Summer Inward Vapor Drives
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30 Forest St Somerville MA 02143
Figure 19 Inward vapor drive relative humidity of poly or GWB for Case 1 Case 2 and Case 9
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30 Forest St Somerville MA 02143
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30 Forest St Somerville MA 02143
Figure 22 Inward vapor drive relative humidity of poly or GWB for Case 8
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30 Forest St Somerville MA 02143
Figure 23 Inward vapor drive relative humidity of poly or GWB for Cases 5 8 and 11
224 Wall Drying
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30 Forest St Somerville MA 02143
Figure 24 Drying Curves for Case 1 and Case 2
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30 Forest St Somerville MA 02143
Figure 26 Drying curves for Case 8
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Building Science Corporation 30 Forest St Somerville MA 02143
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30 Forest St Somerville MA 02143
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30 Forest St Somerville MA 02143
Figure 29 Standard construction practice
111 Thermal Control
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30 Forest St Somerville MA 02143
Figure 30 Therm modeling of Case 1 - 2x6 construction
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112 Moisture Control
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Figure 31 Advanced framing construction
121 Thermal Control
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30 Forest St Somerville MA 02143
Figure 32 Therm modeling of Case 2 advanced framing with 1 XPS insulated sheathing
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122 Moisture Control
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123 Constructability and Cost
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124 Other Considerations
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 33 2x6 wall construction with interior strapping
131 Thermal Control
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30 Forest St Somerville MA 02143
Figure 34 Therm analysis of horizontally strapped wall
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Table 7 Calculated R-value of an interior horizontal strapped wall
132 Moisture Control
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133 Constructability and Cost
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134 Other Considerations
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Figure 35 Double stud wall
141 Thermal Control
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Table 8 Calculated R-value of a double stud wall
142 Moisture Control
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143 Constructability and Cost
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144 Other Considerations
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Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 37 Truss wall construction
151 Thermal Control
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30 Forest St Somerville MA 02143
Figure 38 Therm results of the truss wall
Table 9 Calculated R-value for truss wall
152 Moisture Control
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30 Forest St Somerville MA 02143
153 Constructability and Cost
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154 Other Considerations
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16 Case 6 Structural Insulated Panel Systems (SIPs)
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30 Forest St Somerville MA 02143
161 Thermal Control
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Table 10 Calculated R-value for a Sips wall system
162 Moisture Control
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30 Forest St Somerville MA 02143
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163 Constructability and Cost
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17 Case 7 Insulated Concrete Forms (ICFs)
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30 Forest St Somerville MA 02143
Figure 41 ICF wall construction
171 Thermal Control
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30 Forest St Somerville MA 02143
Figure 42 Nine inch foam ICF with five inches of EPS
Figure 43 Fifteen inch foam ICF with five inches of EPS
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172 Moisture Control
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173 Constructability and Cost
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174 Other Considerations
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30 Forest St Somerville MA 02143
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18 Case 8 Advanced framing with spray foam
13 13 13131313131313
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Figure 44 2x6 wall construction with spray foam insulation
181 Thermal Control
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30 Forest St Somerville MA 02143
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182 Moisture Control
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30 Forest St Somerville MA 02143
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183 Constructability and Cost
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184 Other Considerations
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19 Case 9 Hybrid Wall Insulation ndash Flash and Fill
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 46 Hybrid wall construction with 2 spray foam and fibrous fill
191 Thermal Control
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30 Forest St Somerville MA 02143
Figure 47 Therm analysis of hybrid wall system
Table 12 Calculated R-value for a hybrid wall system
192 Moisture Control
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193 Constructability and Cost
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30 Forest St Somerville MA 02143
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110 Case 10 Double Stud Wall with Spray Foam
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1101 Thermal Control
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Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 49 Therm analysis of double stud wall construction with spray foam
Table 13 Calculated whole wall R-value for a double stud wall system with 2rdquo spray foam
1102 Moisture Control
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30 Forest St Somerville MA 02143
1104 Other Considerations
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30 Forest St Somerville MA 02143
Figure 50 Offset frame wall construction with exterior spray foam
1111 Thermal Control
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30 Forest St Somerville MA 02143
Figure 51 Therm analysis of an offset truss wall with exterior spray foam
Table 14 Calculated whole wall R-value for an offset framed wall with exterior spray foam
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30 Forest St Somerville MA 02143
Figure 52 Wall construction using the EIFS cladding system
1121 Thermal Control
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Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 53 Thermal analysis of an EIFS wall system
Table 15 Calculated whole wall R-value for a EIFS wall system with 4rdquo of EPS
1122 Moisture Control
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30 Forest St Somerville MA 02143
Table 17 Hours of potential winter time air leakage condensation
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Table 18 Wall Comparison Chart
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Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
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30 Forest St Somerville MA 02143
Figure 2 Top plate simulation with 8rdquo of wall
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Figure 4 Plan section of rim joist floor joists and fiberglass batt insulation
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30 Forest St Somerville MA 02143
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Figure 5 Common Convective Heat Flow Paths in Enclosures
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30 Forest St Somerville MA 02143
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Table 2 Conductivity values used for two dimensional heat flow analysis
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30 Forest St Somerville MA 02143
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Building Science Corporation 2 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 3 R-values for analyzed wall systems
22 Hygrothermal Analysis
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Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
222 Wintertime Condensation
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Building Science Corporation 11 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 9 Winter time sheathing relative humidity for Case 1 and Case 2
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30 Forest St Somerville MA 02143
Figure 10 Winter air leakage condensation potential for Case 1 and Case 2
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30 Forest St Somerville MA 02143
Figure 11 Winter air leakage condensation potential for Case 1 and Case 9
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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30 Forest St Somerville MA 02143
Figure 14 Winter air leakage condensation potential for Case 4 and Case 10
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 15 Installation of high density spray foam in an Offset Framed Wall in a cold climate
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 16 Winter time air leakage condensation potential for Case 5 and Case 11
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30 Forest St Somerville MA 02143
Figure 17 Winter time sheathing relative humidity for Case 8
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Building Science Corporation - wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 18 Winter air leakage condensation potential for Case 8
223 Summer Inward Vapor Drives
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Building Science Corporation -+ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 19 Inward vapor drive relative humidity of poly or GWB for Case 1 Case 2 and Case 9
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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30 Forest St Somerville MA 02143
Figure 22 Inward vapor drive relative humidity of poly or GWB for Case 8
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30 Forest St Somerville MA 02143
Figure 23 Inward vapor drive relative humidity of poly or GWB for Cases 5 8 and 11
224 Wall Drying
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Building Science Corporation 02 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 24 Drying Curves for Case 1 and Case 2
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 26 Drying curves for Case 8
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Figure 27 Drying Curves for Case 4 and Case 10 with and without a poly vapor barrier
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Building Science Corporation 30 Forest St Somerville MA 02143
(+ wwwbuildingsciencecom
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23 Enclosure Durability
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24 Buildability
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
25 Material Use
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Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 29 Standard construction practice
111 Thermal Control
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Building Science Corporation - wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 30 Therm modeling of Case 1 - 2x6 construction
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30 Forest St Somerville MA 02143
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30 Forest St Somerville MA 02143
Figure 31 Advanced framing construction
121 Thermal Control
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Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 32 Therm modeling of Case 2 advanced framing with 1 XPS insulated sheathing
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Building Science Corporation 00 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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124 Other Considerations
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 33 2x6 wall construction with interior strapping
131 Thermal Control
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 34 Therm analysis of horizontally strapped wall
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Table 7 Calculated R-value of an interior horizontal strapped wall
132 Moisture Control
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30 Forest St Somerville MA 02143
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134 Other Considerations
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Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 35 Double stud wall
141 Thermal Control
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30 Forest St Somerville MA 02143
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Table 8 Calculated R-value of a double stud wall
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30 Forest St Somerville MA 02143
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Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 37 Truss wall construction
151 Thermal Control
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 38 Therm results of the truss wall
Table 9 Calculated R-value for truss wall
152 Moisture Control
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30 Forest St Somerville MA 02143
153 Constructability and Cost
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Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
161 Thermal Control
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Table 10 Calculated R-value for a Sips wall system
162 Moisture Control
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Building Science Corporation 33 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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17 Case 7 Insulated Concrete Forms (ICFs)
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 41 ICF wall construction
171 Thermal Control
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Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 42 Nine inch foam ICF with five inches of EPS
Figure 43 Fifteen inch foam ICF with five inches of EPS
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173 Constructability and Cost
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174 Other Considerations
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Building Science Corporation () wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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18 Case 8 Advanced framing with spray foam
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181 Thermal Control
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Building Science Corporation amp( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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182 Moisture Control
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Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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184 Other Considerations
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 46 Hybrid wall construction with 2 spray foam and fibrous fill
191 Thermal Control
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30 Forest St Somerville MA 02143
Figure 47 Therm analysis of hybrid wall system
Table 12 Calculated R-value for a hybrid wall system
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Building Science Corporation -+ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 13
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Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 49 Therm analysis of double stud wall construction with spray foam
Table 13 Calculated whole wall R-value for a double stud wall system with 2rdquo spray foam
1102 Moisture Control
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30 Forest St Somerville MA 02143
1104 Other Considerations
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 50 Offset frame wall construction with exterior spray foam
1111 Thermal Control
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Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 51 Therm analysis of an offset truss wall with exterior spray foam
Table 14 Calculated whole wall R-value for an offset framed wall with exterior spray foam
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30 Forest St Somerville MA 02143
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Building Science Corporation 25 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 52 Wall construction using the EIFS cladding system
1121 Thermal Control
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Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 53 Thermal analysis of an EIFS wall system
Table 15 Calculated whole wall R-value for a EIFS wall system with 4rdquo of EPS
1122 Moisture Control
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1123 Constructability and Cost
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Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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30 Forest St Somerville MA 02143
Table 17 Hours of potential winter time air leakage condensation
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30 Forest St Somerville MA 02143
Table 18 Wall Comparison Chart
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30 Forest St Somerville MA 02143
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30 Forest St Somerville MA 02143
E Works Cited
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30 Forest St Somerville MA 02143
Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
Figure 2 Top plate simulation with 8rdquo of wall
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Figure 3 Rim joist simulation with 8 of wall
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Figure 4 Plan section of rim joist floor joists and fiberglass batt insulation
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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Figure 5 Common Convective Heat Flow Paths in Enclosures
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30 Forest St Somerville MA 02143
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Table 2 Conductivity values used for two dimensional heat flow analysis
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Building Science Corporation 6 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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Figure 6 Typical framing 16oc - 9 framing factor
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Figure 7 Actual average framing factor of 23 in standard construction
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Building Science Corporation 2 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 3 R-values for analyzed wall systems
22 Hygrothermal Analysis
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30 Forest St Somerville MA 02143
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221 Moisture Balance
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Figure 8 Moisture balance
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
222 Wintertime Condensation
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Table 4 Vapor control strategies and permeance values for Case 1 and 2
Building Science Corporation 11 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 9 Winter time sheathing relative humidity for Case 1 and Case 2
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30 Forest St Somerville MA 02143
Figure 10 Winter air leakage condensation potential for Case 1 and Case 2
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30 Forest St Somerville MA 02143
Figure 11 Winter air leakage condensation potential for Case 1 and Case 9
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Figure 12 Winter time sheathing relative humidity for Case 3 Case 4 and Case 5
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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Figure 13 Winter air leakage condensation potential for Case 3 Case 4 and Case 5
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Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 14 Winter air leakage condensation potential for Case 4 and Case 10
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 15 Installation of high density spray foam in an Offset Framed Wall in a cold climate
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 16 Winter time air leakage condensation potential for Case 5 and Case 11
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Building Science Corporation +- wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 17 Winter time sheathing relative humidity for Case 8
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Building Science Corporation - wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 18 Winter air leakage condensation potential for Case 8
223 Summer Inward Vapor Drives
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Building Science Corporation -+ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 19 Inward vapor drive relative humidity of poly or GWB for Case 1 Case 2 and Case 9
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Figure 20 Inward vapor drive relative humidity of poly or GWB for Case 3 Case 4 and Case 5
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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Figure 21 Inward vapor drive relative humidity of poly or GWB for Case 4 and Case 10
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 22 Inward vapor drive relative humidity of poly or GWB for Case 8
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Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 23 Inward vapor drive relative humidity of poly or GWB for Cases 5 8 and 11
224 Wall Drying
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Building Science Corporation 02 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 24 Drying Curves for Case 1 and Case 2
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Figure 25 Drying curves for Case 3 Case 4 and Case 5
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 26 Drying curves for Case 8
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Figure 27 Drying Curves for Case 4 and Case 10 with and without a poly vapor barrier
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Building Science Corporation 30 Forest St Somerville MA 02143
(+ wwwbuildingsciencecom
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Figure 28 Drying Curves for Case 5 and Case 11
23 Enclosure Durability
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24 Buildability
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
25 Material Use
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26 Cost
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1 CASE 1 STANDARD CONSTRUCTION PRACTICE
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Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 29 Standard construction practice
111 Thermal Control
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Building Science Corporation - wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 30 Therm modeling of Case 1 - 2x6 construction
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Table 5 Summary of R-value results from Therm modeling for Case 1
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112 Moisture Control
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30 Forest St Somerville MA 02143
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113 Constructability and Cost
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114 Other Considerations
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Building Science Corporation 0 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 31 Advanced framing construction
121 Thermal Control
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Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 32 Therm modeling of Case 2 advanced framing with 1 XPS insulated sheathing
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122 Moisture Control
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Building Science Corporation 00 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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123 Constructability and Cost
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124 Other Considerations
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13 Case 3 Interior 2x3 horizontal strapping
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 33 2x6 wall construction with interior strapping
131 Thermal Control
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 34 Therm analysis of horizontally strapped wall
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Table 7 Calculated R-value of an interior horizontal strapped wall
132 Moisture Control
13
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Building Science Corporation 1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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133 Constructability and Cost
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134 Other Considerations
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14 Case 4 Double Stud
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Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 35 Double stud wall
141 Thermal Control
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30 Forest St Somerville MA 02143
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Figure 36 Therm model of the double stud wall
Table 8 Calculated R-value of a double stud wall
142 Moisture Control
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30 Forest St Somerville MA 02143
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143 Constructability and Cost
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144 Other Considerations
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15 Case 5 Truss Wall
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Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 37 Truss wall construction
151 Thermal Control
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 38 Therm results of the truss wall
Table 9 Calculated R-value for truss wall
152 Moisture Control
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30 Forest St Somerville MA 02143
153 Constructability and Cost
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154 Other Considerations
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16 Case 6 Structural Insulated Panel Systems (SIPs)
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Figure 39 SIPs wall construction
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
161 Thermal Control
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Figure 40 Therm results of SIPs panel analysis
Table 10 Calculated R-value for a Sips wall system
162 Moisture Control
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Building Science Corporation 33 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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163 Constructability and Cost
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17 Case 7 Insulated Concrete Forms (ICFs)
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 41 ICF wall construction
171 Thermal Control
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Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 42 Nine inch foam ICF with five inches of EPS
Figure 43 Fifteen inch foam ICF with five inches of EPS
13 13 1313
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172 Moisture Control
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173 Constructability and Cost
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174 Other Considerations
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Building Science Corporation () wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 1313 13131313 1313 13 13
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13131313
18 Case 8 Advanced framing with spray foam
13 13 13131313131313
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Figure 44 2x6 wall construction with spray foam insulation
181 Thermal Control
13131313 1313131313 13131313131313
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Building Science Corporation amp( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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Table 11 Therm results of spray foam insulation analysis
182 Moisture Control
13 $
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Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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183 Constructability and Cost
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184 Other Considerations
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19 Case 9 Hybrid Wall Insulation ndash Flash and Fill
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 46 Hybrid wall construction with 2 spray foam and fibrous fill
191 Thermal Control
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Building Science Corporation amp$ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 47 Therm analysis of hybrid wall system
Table 12 Calculated R-value for a hybrid wall system
192 Moisture Control
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193 Constructability and Cost
13131313131313
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194 Other Considerations
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Building Science Corporation -+ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 13
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110 Case 10 Double Stud Wall with Spray Foam
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Figure 48 Double stud wall with 2 of spray foam and cellulose fill
1101 Thermal Control
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Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 49 Therm analysis of double stud wall construction with spray foam
Table 13 Calculated whole wall R-value for a double stud wall system with 2rdquo spray foam
1102 Moisture Control
13 13 (13
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1103 Constructability and Cost
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Building Science Corporation )( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1104 Other Considerations
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111 Case 11 Offset Frame Wall with Exterior Spray Foam
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13 13 13 13 13 13
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 50 Offset frame wall construction with exterior spray foam
1111 Thermal Control
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13 13 13 13 13 13 13
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 51 Therm analysis of an offset truss wall with exterior spray foam
Table 14 Calculated whole wall R-value for an offset framed wall with exterior spray foam
1112 Moisture Control
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30 Forest St Somerville MA 02143
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1114 Other Considerations
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112 Case 12 Exterior Insulation Finish System (EIFS)
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30 Forest St Somerville MA 02143
Figure 52 Wall construction using the EIFS cladding system
1121 Thermal Control
1313 1313
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30 Forest St Somerville MA 02143
Figure 53 Thermal analysis of an EIFS wall system
Table 15 Calculated whole wall R-value for a EIFS wall system with 4rdquo of EPS
1122 Moisture Control
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30 Forest St Somerville MA 02143
Table 17 Hours of potential winter time air leakage condensation
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Table 18 Wall Comparison Chart
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E Works Cited
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30 Forest St Somerville MA 02143
Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
1313 131313 1313131313 131313
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Figure 5 Common Convective Heat Flow Paths in Enclosures
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30 Forest St Somerville MA 02143
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Table 2 Conductivity values used for two dimensional heat flow analysis
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30 Forest St Somerville MA 02143
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Figure 6 Typical framing 16oc - 9 framing factor
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Figure 7 Actual average framing factor of 23 in standard construction
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30 Forest St Somerville MA 02143
Table 3 R-values for analyzed wall systems
22 Hygrothermal Analysis
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30 Forest St Somerville MA 02143
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221 Moisture Balance
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Figure 8 Moisture balance
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
222 Wintertime Condensation
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Table 4 Vapor control strategies and permeance values for Case 1 and 2
Building Science Corporation 11 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 9 Winter time sheathing relative humidity for Case 1 and Case 2
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30 Forest St Somerville MA 02143
Figure 10 Winter air leakage condensation potential for Case 1 and Case 2
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30 Forest St Somerville MA 02143
Figure 11 Winter air leakage condensation potential for Case 1 and Case 9
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Figure 12 Winter time sheathing relative humidity for Case 3 Case 4 and Case 5
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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Figure 13 Winter air leakage condensation potential for Case 3 Case 4 and Case 5
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30 Forest St Somerville MA 02143
Figure 14 Winter air leakage condensation potential for Case 4 and Case 10
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 15 Installation of high density spray foam in an Offset Framed Wall in a cold climate
13
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 16 Winter time air leakage condensation potential for Case 5 and Case 11
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Building Science Corporation +- wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 17 Winter time sheathing relative humidity for Case 8
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Building Science Corporation - wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 18 Winter air leakage condensation potential for Case 8
223 Summer Inward Vapor Drives
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Building Science Corporation -+ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 19 Inward vapor drive relative humidity of poly or GWB for Case 1 Case 2 and Case 9
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Figure 20 Inward vapor drive relative humidity of poly or GWB for Case 3 Case 4 and Case 5
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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Figure 21 Inward vapor drive relative humidity of poly or GWB for Case 4 and Case 10
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 22 Inward vapor drive relative humidity of poly or GWB for Case 8
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Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 23 Inward vapor drive relative humidity of poly or GWB for Cases 5 8 and 11
224 Wall Drying
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Building Science Corporation 02 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 24 Drying Curves for Case 1 and Case 2
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Figure 25 Drying curves for Case 3 Case 4 and Case 5
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 26 Drying curves for Case 8
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Figure 27 Drying Curves for Case 4 and Case 10 with and without a poly vapor barrier
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Building Science Corporation 30 Forest St Somerville MA 02143
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Figure 28 Drying Curves for Case 5 and Case 11
23 Enclosure Durability
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24 Buildability
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
25 Material Use
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26 Cost
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1313$13131313 1313131313
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C Results
1 CASE 1 STANDARD CONSTRUCTION PRACTICE
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Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 29 Standard construction practice
111 Thermal Control
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Building Science Corporation - wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 30 Therm modeling of Case 1 - 2x6 construction
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Table 5 Summary of R-value results from Therm modeling for Case 1
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112 Moisture Control
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30 Forest St Somerville MA 02143
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113 Constructability and Cost
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114 Other Considerations
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12 Case 2 Advanced framing with insulated sheathing
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30 Forest St Somerville MA 02143
Figure 31 Advanced framing construction
121 Thermal Control
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1313131313 1313
131313 1313
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Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 32 Therm modeling of Case 2 advanced framing with 1 XPS insulated sheathing
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Table 6 Summary of R-value results from Therm modeling for Case 2
122 Moisture Control
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Building Science Corporation 00 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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123 Constructability and Cost
131313131313
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124 Other Considerations
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13 Case 3 Interior 2x3 horizontal strapping
13 $
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 33 2x6 wall construction with interior strapping
131 Thermal Control
1313 1313131313
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1313 1313 1313131313
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 34 Therm analysis of horizontally strapped wall
13$13-amp0)132amp 13$
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Table 7 Calculated R-value of an interior horizontal strapped wall
132 Moisture Control
13
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30 Forest St Somerville MA 02143
13 13
133 Constructability and Cost
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134 Other Considerations
13
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14 Case 4 Double Stud
1313
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Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 35 Double stud wall
141 Thermal Control
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30 Forest St Somerville MA 02143
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Figure 36 Therm model of the double stud wall
Table 8 Calculated R-value of a double stud wall
142 Moisture Control
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30 Forest St Somerville MA 02143
13
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143 Constructability and Cost
13
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144 Other Considerations
13 13
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15 Case 5 Truss Wall
1313
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13 13 13
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Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 37 Truss wall construction
151 Thermal Control
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30 Forest St Somerville MA 02143
Figure 38 Therm results of the truss wall
Table 9 Calculated R-value for truss wall
152 Moisture Control
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153 Constructability and Cost
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154 Other Considerations
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16 Case 6 Structural Insulated Panel Systems (SIPs)
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Figure 39 SIPs wall construction
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
161 Thermal Control
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Figure 40 Therm results of SIPs panel analysis
Table 10 Calculated R-value for a Sips wall system
162 Moisture Control
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Building Science Corporation 33 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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163 Constructability and Cost
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17 Case 7 Insulated Concrete Forms (ICFs)
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 41 ICF wall construction
171 Thermal Control
1313
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Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 42 Nine inch foam ICF with five inches of EPS
Figure 43 Fifteen inch foam ICF with five inches of EPS
13 13 1313
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172 Moisture Control
1313131313131313 13$amp131313
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173 Constructability and Cost
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174 Other Considerations
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30 Forest St Somerville MA 02143
13 1313 13131313 1313 13 13
13 13 1313 13
131313 13131313131313
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131313131313 131313
13131313
18 Case 8 Advanced framing with spray foam
13 13 13131313131313
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13 $
Figure 44 2x6 wall construction with spray foam insulation
181 Thermal Control
13131313 1313131313 13131313131313
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30 Forest St Somerville MA 02143
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Figure 45 Therm modeling of spray foam wall and rim joist
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Table 11 Therm results of spray foam insulation analysis
182 Moisture Control
13 $
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30 Forest St Somerville MA 02143
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113 13 13 13
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183 Constructability and Cost
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184 Other Considerations
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19 Case 9 Hybrid Wall Insulation ndash Flash and Fill
13 $1313
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 46 Hybrid wall construction with 2 spray foam and fibrous fill
191 Thermal Control
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30 Forest St Somerville MA 02143
Figure 47 Therm analysis of hybrid wall system
Table 12 Calculated R-value for a hybrid wall system
192 Moisture Control
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193 Constructability and Cost
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194 Other Considerations
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30 Forest St Somerville MA 02143
13 13
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110 Case 10 Double Stud Wall with Spray Foam
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Figure 48 Double stud wall with 2 of spray foam and cellulose fill
1101 Thermal Control
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Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 49 Therm analysis of double stud wall construction with spray foam
Table 13 Calculated whole wall R-value for a double stud wall system with 2rdquo spray foam
1102 Moisture Control
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1103 Constructability and Cost
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1104 Other Considerations
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Figure 50 Offset frame wall construction with exterior spray foam
1111 Thermal Control
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30 Forest St Somerville MA 02143
Figure 51 Therm analysis of an offset truss wall with exterior spray foam
Table 14 Calculated whole wall R-value for an offset framed wall with exterior spray foam
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30 Forest St Somerville MA 02143
Figure 52 Wall construction using the EIFS cladding system
1121 Thermal Control
1313 1313
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30 Forest St Somerville MA 02143
Figure 53 Thermal analysis of an EIFS wall system
Table 15 Calculated whole wall R-value for a EIFS wall system with 4rdquo of EPS
1122 Moisture Control
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30 Forest St Somerville MA 02143
Table 17 Hours of potential winter time air leakage condensation
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Table 18 Wall Comparison Chart
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Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
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Table 2 Conductivity values used for two dimensional heat flow analysis
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30 Forest St Somerville MA 02143
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Figure 6 Typical framing 16oc - 9 framing factor
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Figure 7 Actual average framing factor of 23 in standard construction
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30 Forest St Somerville MA 02143
Table 3 R-values for analyzed wall systems
22 Hygrothermal Analysis
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221 Moisture Balance
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Figure 8 Moisture balance
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
222 Wintertime Condensation
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Table 4 Vapor control strategies and permeance values for Case 1 and 2
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30 Forest St Somerville MA 02143
Figure 9 Winter time sheathing relative humidity for Case 1 and Case 2
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30 Forest St Somerville MA 02143
Figure 10 Winter air leakage condensation potential for Case 1 and Case 2
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30 Forest St Somerville MA 02143
Figure 11 Winter air leakage condensation potential for Case 1 and Case 9
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Figure 12 Winter time sheathing relative humidity for Case 3 Case 4 and Case 5
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30 Forest St Somerville MA 02143
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Figure 13 Winter air leakage condensation potential for Case 3 Case 4 and Case 5
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30 Forest St Somerville MA 02143
Figure 14 Winter air leakage condensation potential for Case 4 and Case 10
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 15 Installation of high density spray foam in an Offset Framed Wall in a cold climate
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30 Forest St Somerville MA 02143
Figure 16 Winter time air leakage condensation potential for Case 5 and Case 11
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30 Forest St Somerville MA 02143
Figure 17 Winter time sheathing relative humidity for Case 8
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Building Science Corporation - wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 18 Winter air leakage condensation potential for Case 8
223 Summer Inward Vapor Drives
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30 Forest St Somerville MA 02143
Figure 19 Inward vapor drive relative humidity of poly or GWB for Case 1 Case 2 and Case 9
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Figure 20 Inward vapor drive relative humidity of poly or GWB for Case 3 Case 4 and Case 5
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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Figure 21 Inward vapor drive relative humidity of poly or GWB for Case 4 and Case 10
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 22 Inward vapor drive relative humidity of poly or GWB for Case 8
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30 Forest St Somerville MA 02143
Figure 23 Inward vapor drive relative humidity of poly or GWB for Cases 5 8 and 11
224 Wall Drying
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Building Science Corporation 02 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 24 Drying Curves for Case 1 and Case 2
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Figure 25 Drying curves for Case 3 Case 4 and Case 5
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 26 Drying curves for Case 8
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Figure 27 Drying Curves for Case 4 and Case 10 with and without a poly vapor barrier
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Building Science Corporation 30 Forest St Somerville MA 02143
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Figure 28 Drying Curves for Case 5 and Case 11
23 Enclosure Durability
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24 Buildability
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
25 Material Use
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26 Cost
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C Results
1 CASE 1 STANDARD CONSTRUCTION PRACTICE
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Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 29 Standard construction practice
111 Thermal Control
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Building Science Corporation - wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 30 Therm modeling of Case 1 - 2x6 construction
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Table 5 Summary of R-value results from Therm modeling for Case 1
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13 1313131313
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112 Moisture Control
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30 Forest St Somerville MA 02143
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113 Constructability and Cost
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114 Other Considerations
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30 Forest St Somerville MA 02143
Figure 31 Advanced framing construction
121 Thermal Control
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30 Forest St Somerville MA 02143
Figure 32 Therm modeling of Case 2 advanced framing with 1 XPS insulated sheathing
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Table 6 Summary of R-value results from Therm modeling for Case 2
122 Moisture Control
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124 Other Considerations
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13 Case 3 Interior 2x3 horizontal strapping
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 33 2x6 wall construction with interior strapping
131 Thermal Control
1313 1313131313
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 34 Therm analysis of horizontally strapped wall
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Table 7 Calculated R-value of an interior horizontal strapped wall
132 Moisture Control
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30 Forest St Somerville MA 02143
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133 Constructability and Cost
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134 Other Considerations
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1313
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30 Forest St Somerville MA 02143
Figure 35 Double stud wall
141 Thermal Control
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30 Forest St Somerville MA 02143
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Figure 36 Therm model of the double stud wall
Table 8 Calculated R-value of a double stud wall
142 Moisture Control
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143 Constructability and Cost
13
amp 13
144 Other Considerations
13 13
131313
13 1313
15 Case 5 Truss Wall
1313
13 13131313
13 13 13
131313amp
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 37 Truss wall construction
151 Thermal Control
1313
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 38 Therm results of the truss wall
Table 9 Calculated R-value for truss wall
152 Moisture Control
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30 Forest St Somerville MA 02143
153 Constructability and Cost
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154 Other Considerations
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16 Case 6 Structural Insulated Panel Systems (SIPs)
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Figure 39 SIPs wall construction
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
161 Thermal Control
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Table 10 Calculated R-value for a Sips wall system
162 Moisture Control
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Building Science Corporation 33 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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163 Constructability and Cost
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164 Other Considerations
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17 Case 7 Insulated Concrete Forms (ICFs)
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 41 ICF wall construction
171 Thermal Control
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Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 42 Nine inch foam ICF with five inches of EPS
Figure 43 Fifteen inch foam ICF with five inches of EPS
13 13 1313
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172 Moisture Control
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173 Constructability and Cost
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174 Other Considerations
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30 Forest St Somerville MA 02143
13 1313 13131313 1313 13 13
13 13 1313 13
131313 13131313131313
131313 1313 13 13 1313 13
131313131313 131313
13131313
18 Case 8 Advanced framing with spray foam
13 13 13131313131313
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Figure 44 2x6 wall construction with spray foam insulation
181 Thermal Control
13131313 1313131313 13131313131313
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30 Forest St Somerville MA 02143
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13 amp amp+1+
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Table 11 Therm results of spray foam insulation analysis
182 Moisture Control
13 $
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30 Forest St Somerville MA 02143
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113 13 13 13
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183 Constructability and Cost
13 13 13 13
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184 Other Considerations
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19 Case 9 Hybrid Wall Insulation ndash Flash and Fill
13 $1313
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 46 Hybrid wall construction with 2 spray foam and fibrous fill
191 Thermal Control
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30 Forest St Somerville MA 02143
Figure 47 Therm analysis of hybrid wall system
Table 12 Calculated R-value for a hybrid wall system
192 Moisture Control
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193 Constructability and Cost
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194 Other Considerations
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30 Forest St Somerville MA 02143
13 13
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110 Case 10 Double Stud Wall with Spray Foam
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Figure 48 Double stud wall with 2 of spray foam and cellulose fill
1101 Thermal Control
$) 13
13(amp() $
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Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 49 Therm analysis of double stud wall construction with spray foam
Table 13 Calculated whole wall R-value for a double stud wall system with 2rdquo spray foam
1102 Moisture Control
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1103 Constructability and Cost
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30 Forest St Somerville MA 02143
1104 Other Considerations
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30 Forest St Somerville MA 02143
Figure 50 Offset frame wall construction with exterior spray foam
1111 Thermal Control
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Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 51 Therm analysis of an offset truss wall with exterior spray foam
Table 14 Calculated whole wall R-value for an offset framed wall with exterior spray foam
1112 Moisture Control
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30 Forest St Somerville MA 02143
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Building Science Corporation 25 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 52 Wall construction using the EIFS cladding system
1121 Thermal Control
1313 1313
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Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 53 Thermal analysis of an EIFS wall system
Table 15 Calculated whole wall R-value for a EIFS wall system with 4rdquo of EPS
1122 Moisture Control
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1124 Other Considerations
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30 Forest St Somerville MA 02143
D Conclusions
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30 Forest St Somerville MA 02143
Table 17 Hours of potential winter time air leakage condensation
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30 Forest St Somerville MA 02143
Table 18 Wall Comparison Chart
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E Works Cited
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30 Forest St Somerville MA 02143
Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
131313341313131313
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Figure 6 Typical framing 16oc - 9 framing factor
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Figure 7 Actual average framing factor of 23 in standard construction
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30 Forest St Somerville MA 02143
Table 3 R-values for analyzed wall systems
22 Hygrothermal Analysis
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30 Forest St Somerville MA 02143
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221 Moisture Balance
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Figure 8 Moisture balance
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
222 Wintertime Condensation
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Table 4 Vapor control strategies and permeance values for Case 1 and 2
Building Science Corporation 11 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 9 Winter time sheathing relative humidity for Case 1 and Case 2
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30 Forest St Somerville MA 02143
Figure 10 Winter air leakage condensation potential for Case 1 and Case 2
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30 Forest St Somerville MA 02143
Figure 11 Winter air leakage condensation potential for Case 1 and Case 9
13 $1313
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Figure 12 Winter time sheathing relative humidity for Case 3 Case 4 and Case 5
13$13 13
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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Figure 13 Winter air leakage condensation potential for Case 3 Case 4 and Case 5
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Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 14 Winter air leakage condensation potential for Case 4 and Case 10
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 15 Installation of high density spray foam in an Offset Framed Wall in a cold climate
13
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 16 Winter time air leakage condensation potential for Case 5 and Case 11
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Building Science Corporation +- wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 17 Winter time sheathing relative humidity for Case 8
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Building Science Corporation - wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 18 Winter air leakage condensation potential for Case 8
223 Summer Inward Vapor Drives
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Building Science Corporation -+ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 19 Inward vapor drive relative humidity of poly or GWB for Case 1 Case 2 and Case 9
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Figure 20 Inward vapor drive relative humidity of poly or GWB for Case 3 Case 4 and Case 5
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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Figure 21 Inward vapor drive relative humidity of poly or GWB for Case 4 and Case 10
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 22 Inward vapor drive relative humidity of poly or GWB for Case 8
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Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 23 Inward vapor drive relative humidity of poly or GWB for Cases 5 8 and 11
224 Wall Drying
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Building Science Corporation 02 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 24 Drying Curves for Case 1 and Case 2
13131313 13 13
13 131313
Figure 25 Drying curves for Case 3 Case 4 and Case 5
13 1313
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 26 Drying curves for Case 8
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Figure 27 Drying Curves for Case 4 and Case 10 with and without a poly vapor barrier
131313131313 1313 131313
131313 13131313 13 13
Building Science Corporation 30 Forest St Somerville MA 02143
(+ wwwbuildingsciencecom
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Figure 28 Drying Curves for Case 5 and Case 11
23 Enclosure Durability
13 13 13
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24 Buildability
13 1313
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
25 Material Use
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13 1313131313131313131313
13131313131313$1313131313
1313131313
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26 Cost
13 131313131313
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1313$13131313 1313131313
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C Results
1 CASE 1 STANDARD CONSTRUCTION PRACTICE
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Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 29 Standard construction practice
111 Thermal Control
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Building Science Corporation - wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 30 Therm modeling of Case 1 - 2x6 construction
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13
Table 5 Summary of R-value results from Therm modeling for Case 1
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13 1313131313
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13 13 13 13
112 Moisture Control
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30 Forest St Somerville MA 02143
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113 Constructability and Cost
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114 Other Considerations
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12 Case 2 Advanced framing with insulated sheathing
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Building Science Corporation 0 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 31 Advanced framing construction
121 Thermal Control
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1313131313 1313
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1313131313 1313
131313 1313
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Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 32 Therm modeling of Case 2 advanced framing with 1 XPS insulated sheathing
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Table 6 Summary of R-value results from Therm modeling for Case 2
122 Moisture Control
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Building Science Corporation 00 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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2 131313
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123 Constructability and Cost
131313131313
13130$
13-$131313
131313(13
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13 1313
124 Other Considerations
amp 1313
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1313
13 Case 3 Interior 2x3 horizontal strapping
13 $
13$
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 33 2x6 wall construction with interior strapping
131 Thermal Control
1313 1313131313
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1313131313 1313
131313 13 13131313
1313 1313131313
1313 1313 1313131313
13131313 13
13 13131313$
131313 13
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 34 Therm analysis of horizontally strapped wall
13$13-amp0)132amp 13$
3-1 1amp13 13
amp 13 13amp
Table 7 Calculated R-value of an interior horizontal strapped wall
132 Moisture Control
13
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30 Forest St Somerville MA 02143
13 13
133 Constructability and Cost
1313$
13 13
1313
134 Other Considerations
13
131313
13
14 Case 4 Double Stud
1313
131313
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 35 Double stud wall
141 Thermal Control
13
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30 Forest St Somerville MA 02143
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Figure 36 Therm model of the double stud wall
Table 8 Calculated R-value of a double stud wall
142 Moisture Control
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30 Forest St Somerville MA 02143
13
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143 Constructability and Cost
13
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144 Other Considerations
13 13
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15 Case 5 Truss Wall
1313
13 13131313
13 13 13
131313amp
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 37 Truss wall construction
151 Thermal Control
1313
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13 13
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30 Forest St Somerville MA 02143
Figure 38 Therm results of the truss wall
Table 9 Calculated R-value for truss wall
152 Moisture Control
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30 Forest St Somerville MA 02143
153 Constructability and Cost
13
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154 Other Considerations
13 $$
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16 Case 6 Structural Insulated Panel Systems (SIPs)
131313
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Figure 39 SIPs wall construction
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
161 Thermal Control
13 13
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Figure 40 Therm results of SIPs panel analysis
Table 10 Calculated R-value for a Sips wall system
162 Moisture Control
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Building Science Corporation 33 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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163 Constructability and Cost
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164 Other Considerations
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17 Case 7 Insulated Concrete Forms (ICFs)
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 41 ICF wall construction
171 Thermal Control
1313
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Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 42 Nine inch foam ICF with five inches of EPS
Figure 43 Fifteen inch foam ICF with five inches of EPS
13 13 1313
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172 Moisture Control
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173 Constructability and Cost
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174 Other Considerations
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30 Forest St Somerville MA 02143
13 1313 13131313 1313 13 13
13 13 1313 13
131313 13131313131313
131313 1313 13 13 1313 13
131313131313 131313
13131313
18 Case 8 Advanced framing with spray foam
13 13 13131313131313
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13 $
Figure 44 2x6 wall construction with spray foam insulation
181 Thermal Control
13131313 1313131313 13131313131313
131313131313
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30 Forest St Somerville MA 02143
13amp13 1313$
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Figure 45 Therm modeling of spray foam wall and rim joist
13 amp amp+1+
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Table 11 Therm results of spray foam insulation analysis
182 Moisture Control
13 $
1313 13
131313
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Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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113 13 13 13
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183 Constructability and Cost
13 13 13 13
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184 Other Considerations
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19 Case 9 Hybrid Wall Insulation ndash Flash and Fill
13 $1313
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13 13
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 46 Hybrid wall construction with 2 spray foam and fibrous fill
191 Thermal Control
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30 Forest St Somerville MA 02143
Figure 47 Therm analysis of hybrid wall system
Table 12 Calculated R-value for a hybrid wall system
192 Moisture Control
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193 Constructability and Cost
13131313131313
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194 Other Considerations
1313
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Building Science Corporation -+ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 13
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110 Case 10 Double Stud Wall with Spray Foam
amp 13 13
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Figure 48 Double stud wall with 2 of spray foam and cellulose fill
1101 Thermal Control
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13(amp() $
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Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 49 Therm analysis of double stud wall construction with spray foam
Table 13 Calculated whole wall R-value for a double stud wall system with 2rdquo spray foam
1102 Moisture Control
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1103 Constructability and Cost
13131313 13 13
13131313131313
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30 Forest St Somerville MA 02143
1104 Other Considerations
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30 Forest St Somerville MA 02143
Figure 50 Offset frame wall construction with exterior spray foam
1111 Thermal Control
131313 13 1313131313
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13 13 13 13 13 13 13
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 51 Therm analysis of an offset truss wall with exterior spray foam
Table 14 Calculated whole wall R-value for an offset framed wall with exterior spray foam
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30 Forest St Somerville MA 02143
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Building Science Corporation 25 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 52 Wall construction using the EIFS cladding system
1121 Thermal Control
1313 1313
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Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 53 Thermal analysis of an EIFS wall system
Table 15 Calculated whole wall R-value for a EIFS wall system with 4rdquo of EPS
1122 Moisture Control
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1123 Constructability and Cost
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1124 Other Considerations
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30 Forest St Somerville MA 02143
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Table 16 Summary of all calculated R-values
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30 Forest St Somerville MA 02143
Table 17 Hours of potential winter time air leakage condensation
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30 Forest St Somerville MA 02143
Table 18 Wall Comparison Chart
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30 Forest St Somerville MA 02143
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30 Forest St Somerville MA 02143
Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
Table 3 R-values for analyzed wall systems
22 Hygrothermal Analysis
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30 Forest St Somerville MA 02143
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221 Moisture Balance
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Figure 8 Moisture balance
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
222 Wintertime Condensation
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Table 4 Vapor control strategies and permeance values for Case 1 and 2
Building Science Corporation 11 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 9 Winter time sheathing relative humidity for Case 1 and Case 2
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30 Forest St Somerville MA 02143
Figure 10 Winter air leakage condensation potential for Case 1 and Case 2
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30 Forest St Somerville MA 02143
Figure 11 Winter air leakage condensation potential for Case 1 and Case 9
13 $1313
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Figure 12 Winter time sheathing relative humidity for Case 3 Case 4 and Case 5
13$13 13
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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Figure 13 Winter air leakage condensation potential for Case 3 Case 4 and Case 5
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30 Forest St Somerville MA 02143
Figure 14 Winter air leakage condensation potential for Case 4 and Case 10
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 15 Installation of high density spray foam in an Offset Framed Wall in a cold climate
13
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 16 Winter time air leakage condensation potential for Case 5 and Case 11
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30 Forest St Somerville MA 02143
Figure 17 Winter time sheathing relative humidity for Case 8
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Building Science Corporation - wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 18 Winter air leakage condensation potential for Case 8
223 Summer Inward Vapor Drives
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Building Science Corporation -+ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 19 Inward vapor drive relative humidity of poly or GWB for Case 1 Case 2 and Case 9
13$13 131313
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Figure 20 Inward vapor drive relative humidity of poly or GWB for Case 3 Case 4 and Case 5
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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Figure 21 Inward vapor drive relative humidity of poly or GWB for Case 4 and Case 10
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 22 Inward vapor drive relative humidity of poly or GWB for Case 8
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Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 23 Inward vapor drive relative humidity of poly or GWB for Cases 5 8 and 11
224 Wall Drying
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Building Science Corporation 02 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 24 Drying Curves for Case 1 and Case 2
13131313 13 13
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Figure 25 Drying curves for Case 3 Case 4 and Case 5
13 1313
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 26 Drying curves for Case 8
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Figure 27 Drying Curves for Case 4 and Case 10 with and without a poly vapor barrier
131313131313 1313 131313
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Building Science Corporation 30 Forest St Somerville MA 02143
(+ wwwbuildingsciencecom
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Figure 28 Drying Curves for Case 5 and Case 11
23 Enclosure Durability
13 13 13
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13 13 13 1313
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24 Buildability
13 1313
13131313 13
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
25 Material Use
13131313 1313
13131313$131313
13 1313131313131313131313
13131313131313$1313131313
1313131313
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26 Cost
13 131313131313
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C Results
1 CASE 1 STANDARD CONSTRUCTION PRACTICE
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Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 29 Standard construction practice
111 Thermal Control
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Building Science Corporation - wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 30 Therm modeling of Case 1 - 2x6 construction
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13
Table 5 Summary of R-value results from Therm modeling for Case 1
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112 Moisture Control
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30 Forest St Somerville MA 02143
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113 Constructability and Cost
13
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114 Other Considerations
13
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12 Case 2 Advanced framing with insulated sheathing
1313
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30 Forest St Somerville MA 02143
Figure 31 Advanced framing construction
121 Thermal Control
131313 13$13 1313
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131313 1313
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30 Forest St Somerville MA 02143
Figure 32 Therm modeling of Case 2 advanced framing with 1 XPS insulated sheathing
amp $ $ 13 + 2 3$$35
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Table 6 Summary of R-value results from Therm modeling for Case 2
122 Moisture Control
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30 Forest St Somerville MA 02143
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123 Constructability and Cost
131313131313
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13-$131313
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124 Other Considerations
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13 Case 3 Interior 2x3 horizontal strapping
13 $
13$
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 33 2x6 wall construction with interior strapping
131 Thermal Control
1313 1313131313
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1313131313 1313
131313 13 13131313
1313 1313131313
1313 1313 1313131313
13131313 13
13 13131313$
131313 13
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 34 Therm analysis of horizontally strapped wall
13$13-amp0)132amp 13$
3-1 1amp13 13
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Table 7 Calculated R-value of an interior horizontal strapped wall
132 Moisture Control
13
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30 Forest St Somerville MA 02143
13 13
133 Constructability and Cost
1313$
13 13
1313
134 Other Considerations
13
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14 Case 4 Double Stud
1313
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30 Forest St Somerville MA 02143
Figure 35 Double stud wall
141 Thermal Control
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30 Forest St Somerville MA 02143
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Figure 36 Therm model of the double stud wall
Table 8 Calculated R-value of a double stud wall
142 Moisture Control
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30 Forest St Somerville MA 02143
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143 Constructability and Cost
13
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144 Other Considerations
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15 Case 5 Truss Wall
1313
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Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 37 Truss wall construction
151 Thermal Control
1313
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30 Forest St Somerville MA 02143
Figure 38 Therm results of the truss wall
Table 9 Calculated R-value for truss wall
152 Moisture Control
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30 Forest St Somerville MA 02143
153 Constructability and Cost
13
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154 Other Considerations
13 $$
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16 Case 6 Structural Insulated Panel Systems (SIPs)
131313
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Figure 39 SIPs wall construction
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
161 Thermal Control
13 13
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Figure 40 Therm results of SIPs panel analysis
Table 10 Calculated R-value for a Sips wall system
162 Moisture Control
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Building Science Corporation 33 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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163 Constructability and Cost
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164 Other Considerations
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17 Case 7 Insulated Concrete Forms (ICFs)
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30 Forest St Somerville MA 02143
Figure 41 ICF wall construction
171 Thermal Control
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Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 42 Nine inch foam ICF with five inches of EPS
Figure 43 Fifteen inch foam ICF with five inches of EPS
13 13 1313
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172 Moisture Control
1313131313131313 13$amp131313
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13 1313$1313131313
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173 Constructability and Cost
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174 Other Considerations
13 1313 131313$
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Building Science Corporation () wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 1313 13131313 1313 13 13
13 13 1313 13
131313 13131313131313
131313 1313 13 13 1313 13
131313131313 131313
13131313
18 Case 8 Advanced framing with spray foam
13 13 13131313131313
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13 $
Figure 44 2x6 wall construction with spray foam insulation
181 Thermal Control
13131313 1313131313 13131313131313
131313131313
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30 Forest St Somerville MA 02143
13amp13 1313$
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Figure 45 Therm modeling of spray foam wall and rim joist
13 amp amp+1+
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Table 11 Therm results of spray foam insulation analysis
182 Moisture Control
13 $
1313 13
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Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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113 13 13 13
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183 Constructability and Cost
13 13 13 13
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184 Other Considerations
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19 Case 9 Hybrid Wall Insulation ndash Flash and Fill
13 $1313
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 46 Hybrid wall construction with 2 spray foam and fibrous fill
191 Thermal Control
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Building Science Corporation amp$ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 47 Therm analysis of hybrid wall system
Table 12 Calculated R-value for a hybrid wall system
192 Moisture Control
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193 Constructability and Cost
13131313131313
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194 Other Considerations
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Building Science Corporation -+ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 13
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110 Case 10 Double Stud Wall with Spray Foam
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Figure 48 Double stud wall with 2 of spray foam and cellulose fill
1101 Thermal Control
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Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 49 Therm analysis of double stud wall construction with spray foam
Table 13 Calculated whole wall R-value for a double stud wall system with 2rdquo spray foam
1102 Moisture Control
13 13 (13
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1103 Constructability and Cost
13131313 13 13
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30 Forest St Somerville MA 02143
1104 Other Considerations
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111 Case 11 Offset Frame Wall with Exterior Spray Foam
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30 Forest St Somerville MA 02143
Figure 50 Offset frame wall construction with exterior spray foam
1111 Thermal Control
131313 13 1313131313
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13 13 13 13 13 13 13
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 51 Therm analysis of an offset truss wall with exterior spray foam
Table 14 Calculated whole wall R-value for an offset framed wall with exterior spray foam
1112 Moisture Control
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30 Forest St Somerville MA 02143
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1114 Other Considerations
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112 Case 12 Exterior Insulation Finish System (EIFS)
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Building Science Corporation 25 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 52 Wall construction using the EIFS cladding system
1121 Thermal Control
1313 1313
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1313 131313
13 13 $
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 53 Thermal analysis of an EIFS wall system
Table 15 Calculated whole wall R-value for a EIFS wall system with 4rdquo of EPS
1122 Moisture Control
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1123 Constructability and Cost
131313131313
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1124 Other Considerations
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30 Forest St Somerville MA 02143
D Conclusions
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Table 16 Summary of all calculated R-values
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30 Forest St Somerville MA 02143
Table 17 Hours of potential winter time air leakage condensation
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30 Forest St Somerville MA 02143
Table 18 Wall Comparison Chart
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30 Forest St Somerville MA 02143
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30 Forest St Somerville MA 02143
E Works Cited
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30 Forest St Somerville MA 02143
Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
13
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221 Moisture Balance
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Figure 8 Moisture balance
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
222 Wintertime Condensation
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Table 4 Vapor control strategies and permeance values for Case 1 and 2
Building Science Corporation 11 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 9 Winter time sheathing relative humidity for Case 1 and Case 2
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30 Forest St Somerville MA 02143
Figure 10 Winter air leakage condensation potential for Case 1 and Case 2
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30 Forest St Somerville MA 02143
Figure 11 Winter air leakage condensation potential for Case 1 and Case 9
13 $1313
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Figure 12 Winter time sheathing relative humidity for Case 3 Case 4 and Case 5
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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Figure 13 Winter air leakage condensation potential for Case 3 Case 4 and Case 5
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Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 14 Winter air leakage condensation potential for Case 4 and Case 10
13
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 15 Installation of high density spray foam in an Offset Framed Wall in a cold climate
13
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 16 Winter time air leakage condensation potential for Case 5 and Case 11
13 $$
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Building Science Corporation +- wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 17 Winter time sheathing relative humidity for Case 8
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Building Science Corporation - wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 18 Winter air leakage condensation potential for Case 8
223 Summer Inward Vapor Drives
13 13 131313
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Building Science Corporation -+ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 19 Inward vapor drive relative humidity of poly or GWB for Case 1 Case 2 and Case 9
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Figure 20 Inward vapor drive relative humidity of poly or GWB for Case 3 Case 4 and Case 5
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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Figure 21 Inward vapor drive relative humidity of poly or GWB for Case 4 and Case 10
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 22 Inward vapor drive relative humidity of poly or GWB for Case 8
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Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 23 Inward vapor drive relative humidity of poly or GWB for Cases 5 8 and 11
224 Wall Drying
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Building Science Corporation 02 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 24 Drying Curves for Case 1 and Case 2
13131313 13 13
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Figure 25 Drying curves for Case 3 Case 4 and Case 5
13 1313
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 26 Drying curves for Case 8
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1313131313 13131313 131313
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Figure 27 Drying Curves for Case 4 and Case 10 with and without a poly vapor barrier
131313131313 1313 131313
131313 13131313 13 13
Building Science Corporation 30 Forest St Somerville MA 02143
(+ wwwbuildingsciencecom
13 1313
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Figure 28 Drying Curves for Case 5 and Case 11
23 Enclosure Durability
13 13 13
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13 13 13 1313
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24 Buildability
13 1313
13131313 13
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1313
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
25 Material Use
13131313 1313
13131313$131313
13 1313131313131313131313
13131313131313$1313131313
1313131313
131313$
26 Cost
13 131313131313
1313$1313131313
13131313 1313
13$13amp1313 213
1313 )+$1313 13)-$+
1313$13131313 1313131313
131313$
C Results
1 CASE 1 STANDARD CONSTRUCTION PRACTICE
131313131313--0130(13
13131301313131313133 13$)-2
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Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 29 Standard construction practice
111 Thermal Control
13) amp( 13
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Building Science Corporation - wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 30 Therm modeling of Case 1 - 2x6 construction
1313 13 13 131313 (-$13
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13131313131313131313
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Table 5 Summary of R-value results from Therm modeling for Case 1
1313131313131313131313
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112 Moisture Control
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30 Forest St Somerville MA 02143
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113 Constructability and Cost
13
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114 Other Considerations
13
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131+13
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13amp
12 Case 2 Advanced framing with insulated sheathing
1313
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30 Forest St Somerville MA 02143
Figure 31 Advanced framing construction
121 Thermal Control
131313 13$13 1313
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1313131313 1313
131313 1313
13131313131313
131313amp1313 13
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 32 Therm modeling of Case 2 advanced framing with 1 XPS insulated sheathing
amp $ $ 13 + 2 3$$35
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Table 6 Summary of R-value results from Therm modeling for Case 2
122 Moisture Control
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30 Forest St Somerville MA 02143
131313$ 1313
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123 Constructability and Cost
131313131313
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13-$131313
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124 Other Considerations
amp 1313
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1313
13 Case 3 Interior 2x3 horizontal strapping
13 $
13$
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 33 2x6 wall construction with interior strapping
131 Thermal Control
1313 1313131313
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1313131313 1313
131313 13 13131313
1313 1313131313
1313 1313 1313131313
13131313 13
13 13131313$
131313 13
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 34 Therm analysis of horizontally strapped wall
13$13-amp0)132amp 13$
3-1 1amp13 13
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Table 7 Calculated R-value of an interior horizontal strapped wall
132 Moisture Control
13
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30 Forest St Somerville MA 02143
13 13
133 Constructability and Cost
1313$
13 13
1313
134 Other Considerations
13
131313
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14 Case 4 Double Stud
1313
131313
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 35 Double stud wall
141 Thermal Control
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30 Forest St Somerville MA 02143
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Figure 36 Therm model of the double stud wall
Table 8 Calculated R-value of a double stud wall
142 Moisture Control
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30 Forest St Somerville MA 02143
13
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143 Constructability and Cost
13
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144 Other Considerations
13 13
131313
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15 Case 5 Truss Wall
1313
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131313amp
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 37 Truss wall construction
151 Thermal Control
1313
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131313
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 38 Therm results of the truss wall
Table 9 Calculated R-value for truss wall
152 Moisture Control
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30 Forest St Somerville MA 02143
153 Constructability and Cost
13
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154 Other Considerations
13 $$
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16 Case 6 Structural Insulated Panel Systems (SIPs)
131313
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Figure 39 SIPs wall construction
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
161 Thermal Control
13 13
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Figure 40 Therm results of SIPs panel analysis
Table 10 Calculated R-value for a Sips wall system
162 Moisture Control
13 $ $ amp
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Building Science Corporation 33 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($$
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163 Constructability and Cost
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164 Other Considerations
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17 Case 7 Insulated Concrete Forms (ICFs)
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 41 ICF wall construction
171 Thermal Control
1313
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Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 42 Nine inch foam ICF with five inches of EPS
Figure 43 Fifteen inch foam ICF with five inches of EPS
13 13 1313
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172 Moisture Control
1313131313131313 13$amp131313
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13 1313$1313131313
131313amp13
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173 Constructability and Cost
13131313 $1313$13$ 13
13 13$1313amp13$13
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13$13 13$131313
131313 1313 13$amp
174 Other Considerations
13 1313 131313$
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Building Science Corporation () wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 1313 13131313 1313 13 13
13 13 1313 13
131313 13131313131313
131313 1313 13 13 1313 13
131313131313 131313
13131313
18 Case 8 Advanced framing with spray foam
13 13 13131313131313
13131313131313 13$
13 $
Figure 44 2x6 wall construction with spray foam insulation
181 Thermal Control
13131313 1313131313 13131313131313
131313131313
Building Science Corporation amp( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13amp13 1313$
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Figure 45 Therm modeling of spray foam wall and rim joist
13 amp amp+1+
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Table 11 Therm results of spray foam insulation analysis
182 Moisture Control
13 $
1313 13
131313
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Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313 13 13
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113 13 13 13
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183 Constructability and Cost
13 13 13 13
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184 Other Considerations
1313
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19 Case 9 Hybrid Wall Insulation ndash Flash and Fill
13 $1313
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1313 13 0amp $
13 13
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 46 Hybrid wall construction with 2 spray foam and fibrous fill
191 Thermal Control
131313131313
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Building Science Corporation amp$ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 47 Therm analysis of hybrid wall system
Table 12 Calculated R-value for a hybrid wall system
192 Moisture Control
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193 Constructability and Cost
13131313131313
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194 Other Considerations
1313
1313 1313
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Building Science Corporation -+ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 13
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110 Case 10 Double Stud Wall with Spray Foam
amp 13 13
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Figure 48 Double stud wall with 2 of spray foam and cellulose fill
1101 Thermal Control
$) 13
13(amp() $
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Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 49 Therm analysis of double stud wall construction with spray foam
Table 13 Calculated whole wall R-value for a double stud wall system with 2rdquo spray foam
1102 Moisture Control
13 13 (13
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13 1313 1313 13 13
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1103 Constructability and Cost
13131313 13 13
13131313131313
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30 Forest St Somerville MA 02143
1104 Other Considerations
13 13 13 1313
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111 Case 11 Offset Frame Wall with Exterior Spray Foam
131313 1313 13 1313
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13 13 13 13 13 13
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30 Forest St Somerville MA 02143
Figure 50 Offset frame wall construction with exterior spray foam
1111 Thermal Control
131313 13 1313131313
1313 131313
13 13 13131313
13 13 13 13 13 13 13
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 51 Therm analysis of an offset truss wall with exterior spray foam
Table 14 Calculated whole wall R-value for an offset framed wall with exterior spray foam
1112 Moisture Control
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30 Forest St Somerville MA 02143
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1114 Other Considerations
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112 Case 12 Exterior Insulation Finish System (EIFS)
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Building Science Corporation 25 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 52 Wall construction using the EIFS cladding system
1121 Thermal Control
1313 1313
1313 1313
1313 131313
13 13 $
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 53 Thermal analysis of an EIFS wall system
Table 15 Calculated whole wall R-value for a EIFS wall system with 4rdquo of EPS
1122 Moisture Control
1313131313131313
131313amp1313
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1123 Constructability and Cost
131313131313
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1124 Other Considerations
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30 Forest St Somerville MA 02143
D Conclusions
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Table 16 Summary of all calculated R-values
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Building Science Corporation -) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 17 Hours of potential winter time air leakage condensation
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30 Forest St Somerville MA 02143
Table 18 Wall Comparison Chart
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30 Forest St Somerville MA 02143
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30 Forest St Somerville MA 02143
E Works Cited
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30 Forest St Somerville MA 02143
Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
222 Wintertime Condensation
13 +
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+ $
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Table 4 Vapor control strategies and permeance values for Case 1 and 2
Building Science Corporation 11 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 9 Winter time sheathing relative humidity for Case 1 and Case 2
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Building Science Corporation - wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 10 Winter air leakage condensation potential for Case 1 and Case 2
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30 Forest St Somerville MA 02143
Figure 11 Winter air leakage condensation potential for Case 1 and Case 9
13 $1313
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Figure 12 Winter time sheathing relative humidity for Case 3 Case 4 and Case 5
13$13 13
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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Figure 13 Winter air leakage condensation potential for Case 3 Case 4 and Case 5
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Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 14 Winter air leakage condensation potential for Case 4 and Case 10
13
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 15 Installation of high density spray foam in an Offset Framed Wall in a cold climate
13
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 16 Winter time air leakage condensation potential for Case 5 and Case 11
13 $$
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Building Science Corporation +- wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 17 Winter time sheathing relative humidity for Case 8
13131313 13 131313
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131313131313131313
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Building Science Corporation - wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 18 Winter air leakage condensation potential for Case 8
223 Summer Inward Vapor Drives
13 13 131313
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Building Science Corporation -+ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 19 Inward vapor drive relative humidity of poly or GWB for Case 1 Case 2 and Case 9
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Figure 20 Inward vapor drive relative humidity of poly or GWB for Case 3 Case 4 and Case 5
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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Figure 21 Inward vapor drive relative humidity of poly or GWB for Case 4 and Case 10
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 22 Inward vapor drive relative humidity of poly or GWB for Case 8
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Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 23 Inward vapor drive relative humidity of poly or GWB for Cases 5 8 and 11
224 Wall Drying
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Building Science Corporation 02 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 24 Drying Curves for Case 1 and Case 2
13131313 13 13
13 131313
Figure 25 Drying curves for Case 3 Case 4 and Case 5
13 1313
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 26 Drying curves for Case 8
1313 1313$13)1313
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13131313131313131313131313 13
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Figure 27 Drying Curves for Case 4 and Case 10 with and without a poly vapor barrier
131313131313 1313 131313
131313 13131313 13 13
Building Science Corporation 30 Forest St Somerville MA 02143
(+ wwwbuildingsciencecom
13 1313
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Figure 28 Drying Curves for Case 5 and Case 11
23 Enclosure Durability
13 13 13
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13 13 13 1313
13131313 13
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24 Buildability
13 1313
13131313 13
1313 13 13131313
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
25 Material Use
13131313 1313
13131313$131313
13 1313131313131313131313
13131313131313$1313131313
1313131313
131313$
26 Cost
13 131313131313
1313$1313131313
13131313 1313
13$13amp1313 213
1313 )+$1313 13)-$+
1313$13131313 1313131313
131313$
C Results
1 CASE 1 STANDARD CONSTRUCTION PRACTICE
131313131313--0130(13
13131301313131313133 13$)-2
131313 13131313$
Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 29 Standard construction practice
111 Thermal Control
13) amp( 13
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13 $ 13 13
13 13
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Building Science Corporation - wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 30 Therm modeling of Case 1 - 2x6 construction
1313 13 13 131313 (-$13
13 131313 1313 13
131313) )13131313131313(-131313
13131313131313131313
13 13131313131313131313)+
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13
Table 5 Summary of R-value results from Therm modeling for Case 1
1313131313131313131313
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13 1313131313
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112 Moisture Control
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30 Forest St Somerville MA 02143
131313
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113 Constructability and Cost
13
amp13
13amp
114 Other Considerations
13
13amp
131+13
amp 13
13amp
12 Case 2 Advanced framing with insulated sheathing
1313
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30 Forest St Somerville MA 02143
Figure 31 Advanced framing construction
121 Thermal Control
131313 13$13 1313
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$$)amp $$)13$$13 13) 13
1313131313 1313
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+(13$13$1313$1313amp13
1313131313 1313
131313 1313
13131313131313
131313amp1313 13
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 32 Therm modeling of Case 2 advanced framing with 1 XPS insulated sheathing
amp $ $ 13 + 2 3$$35
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Table 6 Summary of R-value results from Therm modeling for Case 2
122 Moisture Control
$
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30 Forest St Somerville MA 02143
131313$ 1313
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2 131313
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123 Constructability and Cost
131313131313
13130$
13-$131313
131313(13
$$13131313
13 1313
124 Other Considerations
amp 1313
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131313$1313 13
1313
13 Case 3 Interior 2x3 horizontal strapping
13 $
13$
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 33 2x6 wall construction with interior strapping
131 Thermal Control
1313 1313131313
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1313131313 1313
131313 13 13131313
1313 1313131313
1313 1313 1313131313
13131313 13
13 13131313$
131313 13
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 34 Therm analysis of horizontally strapped wall
13$13-amp0)132amp 13$
3-1 1amp13 13
amp 13 13amp
Table 7 Calculated R-value of an interior horizontal strapped wall
132 Moisture Control
13
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13 $amp
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30 Forest St Somerville MA 02143
13 13
133 Constructability and Cost
1313$
13 13
1313
134 Other Considerations
13
131313
13
14 Case 4 Double Stud
1313
131313
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30 Forest St Somerville MA 02143
Figure 35 Double stud wall
141 Thermal Control
13
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30 Forest St Somerville MA 02143
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Figure 36 Therm model of the double stud wall
Table 8 Calculated R-value of a double stud wall
142 Moisture Control
13131313
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30 Forest St Somerville MA 02143
13
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13 1313
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143 Constructability and Cost
13
amp 13
144 Other Considerations
13 13
131313
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15 Case 5 Truss Wall
1313
13 13131313
13 13 13
131313amp
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 37 Truss wall construction
151 Thermal Control
1313
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131313
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13 13
13131313
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 38 Therm results of the truss wall
Table 9 Calculated R-value for truss wall
152 Moisture Control
13
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30 Forest St Somerville MA 02143
153 Constructability and Cost
13
13131313
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154 Other Considerations
13 $$
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16 Case 6 Structural Insulated Panel Systems (SIPs)
131313
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Figure 39 SIPs wall construction
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
161 Thermal Control
13 13
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Figure 40 Therm results of SIPs panel analysis
Table 10 Calculated R-value for a Sips wall system
162 Moisture Control
13 $ $ amp
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)
Building Science Corporation 33 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($$
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163 Constructability and Cost
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164 Other Considerations
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17 Case 7 Insulated Concrete Forms (ICFs)
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 41 ICF wall construction
171 Thermal Control
1313
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amp)$)
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 42 Nine inch foam ICF with five inches of EPS
Figure 43 Fifteen inch foam ICF with five inches of EPS
13 13 1313
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172 Moisture Control
1313131313131313 13$amp131313
131313 13amp13
$ 13$1313$13ampamp
13 1313$1313131313
131313amp13
1313131313 13amp
173 Constructability and Cost
13131313 $1313$13$ 13
13 13$1313amp13$13
1313 amp13 13
13 13 1313$
13$13 13$131313
131313 1313 13$amp
174 Other Considerations
13 1313 131313$
13$$131313 1313 13
13amp131313$ 131313
1313 13amp13 131313
Building Science Corporation () wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 1313 13131313 1313 13 13
13 13 1313 13
131313 13131313131313
131313 1313 13 13 1313 13
131313131313 131313
13131313
18 Case 8 Advanced framing with spray foam
13 13 13131313131313
13131313131313 13$
13 $
Figure 44 2x6 wall construction with spray foam insulation
181 Thermal Control
13131313 1313131313 13131313131313
131313131313
Building Science Corporation amp( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13amp13 1313$
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Figure 45 Therm modeling of spray foam wall and rim joist
13 amp amp+1+
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Table 11 Therm results of spray foam insulation analysis
182 Moisture Control
13 $
1313 13
131313
13
Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313 13 13
13 13 $ 13
131313 23
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13 13
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1313 13
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1313 13 13
13 1313$
(+) 13 13 1313+-
113 13 13 13
-1313+-$
183 Constructability and Cost
13 13 13 13
$13 13
1313 13 13$
184 Other Considerations
1313
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19 Case 9 Hybrid Wall Insulation ndash Flash and Fill
13 $1313
1313 $13
131313$13 131313
13 13$
1313 13 0amp $
13 13
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 46 Hybrid wall construction with 2 spray foam and fibrous fill
191 Thermal Control
131313131313
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Building Science Corporation amp$ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 47 Therm analysis of hybrid wall system
Table 12 Calculated R-value for a hybrid wall system
192 Moisture Control
+ amp 13
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193 Constructability and Cost
13131313131313
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194 Other Considerations
1313
1313 1313
1313
Building Science Corporation -+ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 13
13
110 Case 10 Double Stud Wall with Spray Foam
amp 13 13
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13
Figure 48 Double stud wall with 2 of spray foam and cellulose fill
1101 Thermal Control
$) 13
13(amp() $
13$
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 49 Therm analysis of double stud wall construction with spray foam
Table 13 Calculated whole wall R-value for a double stud wall system with 2rdquo spray foam
1102 Moisture Control
13 13 (13
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13 1313 13
13 13
($$13(amp$$$13
13 1313 1313 13 13
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1103 Constructability and Cost
13131313 13 13
13131313131313
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30 Forest St Somerville MA 02143
1104 Other Considerations
13 13 13 1313
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111 Case 11 Offset Frame Wall with Exterior Spray Foam
131313 1313 13 1313
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13 13 13 13 13 13
$ 13 ( 1313 13 131313131313
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 50 Offset frame wall construction with exterior spray foam
1111 Thermal Control
131313 13 1313131313
1313 131313
13 13 13131313
13 13 13 13 13 13 13
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 51 Therm analysis of an offset truss wall with exterior spray foam
Table 14 Calculated whole wall R-value for an offset framed wall with exterior spray foam
1112 Moisture Control
13
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13 131313
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1113 Constructability and Cost
13 $13
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30 Forest St Somerville MA 02143
$($( $$
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1114 Other Considerations
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112 Case 12 Exterior Insulation Finish System (EIFS)
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Building Science Corporation 25 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 52 Wall construction using the EIFS cladding system
1121 Thermal Control
1313 1313
1313 1313
1313 131313
13 13 $
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 53 Thermal analysis of an EIFS wall system
Table 15 Calculated whole wall R-value for a EIFS wall system with 4rdquo of EPS
1122 Moisture Control
1313131313131313
131313amp1313
13131313
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1313131313 131313) amp
1123 Constructability and Cost
131313131313
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131313131313 1313 13
1313amp
1124 Other Considerations
131313131313amp 13
13131313 131313
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1313131313amp 131313131313
131313131313amp
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30 Forest St Somerville MA 02143
D Conclusions
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13131313 1313
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Table 16 Summary of all calculated R-values
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30 Forest St Somerville MA 02143
Table 17 Hours of potential winter time air leakage condensation
13
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30 Forest St Somerville MA 02143
Table 18 Wall Comparison Chart
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13 13 amp
$13$1313$ 13$
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$ $13$ amp13 $13
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13 $amp13
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30 Forest St Somerville MA 02143
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30 Forest St Somerville MA 02143
E Works Cited
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30 Forest St Somerville MA 02143
Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
Figure 9 Winter time sheathing relative humidity for Case 1 and Case 2
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30 Forest St Somerville MA 02143
Figure 10 Winter air leakage condensation potential for Case 1 and Case 2
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 11 Winter air leakage condensation potential for Case 1 and Case 9
13 $1313
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Figure 12 Winter time sheathing relative humidity for Case 3 Case 4 and Case 5
13$13 13
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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Figure 13 Winter air leakage condensation potential for Case 3 Case 4 and Case 5
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Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 14 Winter air leakage condensation potential for Case 4 and Case 10
13
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 15 Installation of high density spray foam in an Offset Framed Wall in a cold climate
13
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 16 Winter time air leakage condensation potential for Case 5 and Case 11
13 $$
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$ $amp $ $ampamp
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Building Science Corporation +- wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 17 Winter time sheathing relative humidity for Case 8
13131313 13 131313
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13 131313amp)1313131313
13131313131313 13 13131313
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131313131313131313
13131313131313 13
Building Science Corporation - wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 18 Winter air leakage condensation potential for Case 8
223 Summer Inward Vapor Drives
13 13 131313
1313 1313$1313 1313
1313 1313$13 13$13131313$
1313 13 $13
13131313
1313
13 13 131313 131313
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13131313 13 1313$1313
1313 1313$1313
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Building Science Corporation -+ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 19 Inward vapor drive relative humidity of poly or GWB for Case 1 Case 2 and Case 9
13$13 131313
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13131313131313
Figure 20 Inward vapor drive relative humidity of poly or GWB for Case 3 Case 4 and Case 5
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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Figure 21 Inward vapor drive relative humidity of poly or GWB for Case 4 and Case 10
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 22 Inward vapor drive relative humidity of poly or GWB for Case 8
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Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 23 Inward vapor drive relative humidity of poly or GWB for Cases 5 8 and 11
224 Wall Drying
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Building Science Corporation 02 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 24 Drying Curves for Case 1 and Case 2
13131313 13 13
13 131313
Figure 25 Drying curves for Case 3 Case 4 and Case 5
13 1313
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 26 Drying curves for Case 8
1313 1313$13)1313
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13(13131313 13)13 13 13
13131313131313131313131313 13
1313131313 13131313 131313
131313131313131313131313131313 13
Figure 27 Drying Curves for Case 4 and Case 10 with and without a poly vapor barrier
131313131313 1313 131313
131313 13131313 13 13
Building Science Corporation 30 Forest St Somerville MA 02143
(+ wwwbuildingsciencecom
13 1313
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Figure 28 Drying Curves for Case 5 and Case 11
23 Enclosure Durability
13 13 13
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13 131313
13 13 13 1313
13131313 13
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24 Buildability
13 1313
13131313 13
1313 13 13131313
1313
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
25 Material Use
13131313 1313
13131313$131313
13 1313131313131313131313
13131313131313$1313131313
1313131313
131313$
26 Cost
13 131313131313
1313$1313131313
13131313 1313
13$13amp1313 213
1313 )+$1313 13)-$+
1313$13131313 1313131313
131313$
C Results
1 CASE 1 STANDARD CONSTRUCTION PRACTICE
131313131313--0130(13
13131301313131313133 13$)-2
131313 13131313$
Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 29 Standard construction practice
111 Thermal Control
13) amp( 13
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13 $ 13 13
13 13
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Building Science Corporation - wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 30 Therm modeling of Case 1 - 2x6 construction
1313 13 13 131313 (-$13
13 131313 1313 13
131313) )13131313131313(-131313
13131313131313131313
13 13131313131313131313)+
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13
Table 5 Summary of R-value results from Therm modeling for Case 1
1313131313131313131313
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13 1313131313
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112 Moisture Control
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30 Forest St Somerville MA 02143
131313
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113 Constructability and Cost
13
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114 Other Considerations
13
13amp
131+13
amp 13
13amp
12 Case 2 Advanced framing with insulated sheathing
1313
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30 Forest St Somerville MA 02143
Figure 31 Advanced framing construction
121 Thermal Control
131313 13$13 1313
1313 13$13$1313 13
$$)amp $$)13$$13 13) 13
1313131313 1313
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+(13$13$1313$1313amp13
1313131313 1313
131313 1313
13131313131313
131313amp1313 13
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 32 Therm modeling of Case 2 advanced framing with 1 XPS insulated sheathing
amp $ $ 13 + 2 3$$35
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Table 6 Summary of R-value results from Therm modeling for Case 2
122 Moisture Control
$
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Building Science Corporation 00 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
131313$ 1313
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2 131313
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123 Constructability and Cost
131313131313
13130$
13-$131313
131313(13
$$13131313
13 1313
124 Other Considerations
amp 1313
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131313$1313 13
1313
13 Case 3 Interior 2x3 horizontal strapping
13 $
13$
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 33 2x6 wall construction with interior strapping
131 Thermal Control
1313 1313131313
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1313131313 1313
131313 13 13131313
1313 1313131313
1313 1313 1313131313
13131313 13
13 13131313$
131313 13
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 34 Therm analysis of horizontally strapped wall
13$13-amp0)132amp 13$
3-1 1amp13 13
amp 13 13amp
Table 7 Calculated R-value of an interior horizontal strapped wall
132 Moisture Control
13
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13 $amp
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30 Forest St Somerville MA 02143
13 13
133 Constructability and Cost
1313$
13 13
1313
134 Other Considerations
13
131313
13
14 Case 4 Double Stud
1313
131313
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 35 Double stud wall
141 Thermal Control
13
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30 Forest St Somerville MA 02143
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Figure 36 Therm model of the double stud wall
Table 8 Calculated R-value of a double stud wall
142 Moisture Control
13131313
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131313
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30 Forest St Somerville MA 02143
13
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13 1313
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143 Constructability and Cost
13
amp 13
144 Other Considerations
13 13
131313
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15 Case 5 Truss Wall
1313
13 13131313
13 13 13
131313amp
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 37 Truss wall construction
151 Thermal Control
1313
13 13(
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131313
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13 13
13131313
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 38 Therm results of the truss wall
Table 9 Calculated R-value for truss wall
152 Moisture Control
13
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30 Forest St Somerville MA 02143
153 Constructability and Cost
13
13131313
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154 Other Considerations
13 $$
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16 Case 6 Structural Insulated Panel Systems (SIPs)
131313
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Figure 39 SIPs wall construction
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
161 Thermal Control
13 13
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Figure 40 Therm results of SIPs panel analysis
Table 10 Calculated R-value for a Sips wall system
162 Moisture Control
13 $ $ amp
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)
Building Science Corporation 33 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($$
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163 Constructability and Cost
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164 Other Considerations
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17 Case 7 Insulated Concrete Forms (ICFs)
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 41 ICF wall construction
171 Thermal Control
1313
1313 1313
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amp)$)
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 42 Nine inch foam ICF with five inches of EPS
Figure 43 Fifteen inch foam ICF with five inches of EPS
13 13 1313
13 1313131313$13$1313
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172 Moisture Control
1313131313131313 13$amp131313
131313 13amp13
$ 13$1313$13ampamp
13 1313$1313131313
131313amp13
1313131313 13amp
173 Constructability and Cost
13131313 $1313$13$ 13
13 13$1313amp13$13
1313 amp13 13
13 13 1313$
13$13 13$131313
131313 1313 13$amp
174 Other Considerations
13 1313 131313$
13$$131313 1313 13
13amp131313$ 131313
1313 13amp13 131313
Building Science Corporation () wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 1313 13131313 1313 13 13
13 13 1313 13
131313 13131313131313
131313 1313 13 13 1313 13
131313131313 131313
13131313
18 Case 8 Advanced framing with spray foam
13 13 13131313131313
13131313131313 13$
13 $
Figure 44 2x6 wall construction with spray foam insulation
181 Thermal Control
13131313 1313131313 13131313131313
131313131313
Building Science Corporation amp( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13amp13 1313$
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Figure 45 Therm modeling of spray foam wall and rim joist
13 amp amp+1+
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Table 11 Therm results of spray foam insulation analysis
182 Moisture Control
13 $
1313 13
131313
13
Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313 13 13
13 13 $ 13
131313 23
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13 13
1313
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1313 13
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1313 13 13
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(+) 13 13 1313+-
113 13 13 13
-1313+-$
183 Constructability and Cost
13 13 13 13
$13 13
1313 13 13$
184 Other Considerations
1313
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19 Case 9 Hybrid Wall Insulation ndash Flash and Fill
13 $1313
1313 $13
131313$13 131313
13 13$
1313 13 0amp $
13 13
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13 $
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 46 Hybrid wall construction with 2 spray foam and fibrous fill
191 Thermal Control
131313131313
13 1313 13
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13 13 13 13
1313
Building Science Corporation amp$ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 47 Therm analysis of hybrid wall system
Table 12 Calculated R-value for a hybrid wall system
192 Moisture Control
+ amp 13
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193 Constructability and Cost
13131313131313
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194 Other Considerations
1313
1313 1313
1313
Building Science Corporation -+ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 13
13
110 Case 10 Double Stud Wall with Spray Foam
amp 13 13
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131313
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13
Figure 48 Double stud wall with 2 of spray foam and cellulose fill
1101 Thermal Control
$) 13
13(amp() $
13$
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 49 Therm analysis of double stud wall construction with spray foam
Table 13 Calculated whole wall R-value for a double stud wall system with 2rdquo spray foam
1102 Moisture Control
13 13 (13
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13 1313 13
13 13
($$13(amp$$$13
13 1313 1313 13 13
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1313 amp+ 13
1313 amp1313 13
13 1313 amp
1313 13 13
1103 Constructability and Cost
13131313 13 13
13131313131313
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30 Forest St Somerville MA 02143
1104 Other Considerations
13 13 13 1313
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13 13 (
131313 1313 13 13 13 13
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111 Case 11 Offset Frame Wall with Exterior Spray Foam
131313 1313 13 1313
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13 1313$ 13 13 13(
13 13 13 13 13 13
$ 13 ( 1313 13 131313131313
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 50 Offset frame wall construction with exterior spray foam
1111 Thermal Control
131313 13 1313131313
1313 131313
13 13 13131313
13 13 13 13 13 13 13
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 51 Therm analysis of an offset truss wall with exterior spray foam
Table 14 Calculated whole wall R-value for an offset framed wall with exterior spray foam
1112 Moisture Control
13
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13 131313
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1113 Constructability and Cost
13 $13
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30 Forest St Somerville MA 02143
$($( $$
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1114 Other Considerations
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112 Case 12 Exterior Insulation Finish System (EIFS)
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Building Science Corporation 25 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 52 Wall construction using the EIFS cladding system
1121 Thermal Control
1313 1313
1313 1313
1313 131313
13 13 $
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 53 Thermal analysis of an EIFS wall system
Table 15 Calculated whole wall R-value for a EIFS wall system with 4rdquo of EPS
1122 Moisture Control
1313131313131313
131313amp1313
13131313
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13131313131313
13 13 13+ 13amp 131313
1313131313 131313) amp
1123 Constructability and Cost
131313131313
131313amp1313131313amp
131313131313 1313 13
1313amp
1124 Other Considerations
131313131313amp 13
13131313 131313
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1313131313amp 131313131313
131313131313amp
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30 Forest St Somerville MA 02143
D Conclusions
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13131313 1313
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Table 16 Summary of all calculated R-values
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Building Science Corporation -) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 17 Hours of potential winter time air leakage condensation
13
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30 Forest St Somerville MA 02143
Table 18 Wall Comparison Chart
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13 13 amp
$13$1313$ 13$
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30 Forest St Somerville MA 02143
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30 Forest St Somerville MA 02143
E Works Cited
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30 Forest St Somerville MA 02143
Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
Figure 10 Winter air leakage condensation potential for Case 1 and Case 2
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30 Forest St Somerville MA 02143
Figure 11 Winter air leakage condensation potential for Case 1 and Case 9
13 $1313
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Figure 12 Winter time sheathing relative humidity for Case 3 Case 4 and Case 5
13$13 13
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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Figure 13 Winter air leakage condensation potential for Case 3 Case 4 and Case 5
1313 131313$1313$13
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Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 14 Winter air leakage condensation potential for Case 4 and Case 10
13
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 15 Installation of high density spray foam in an Offset Framed Wall in a cold climate
13
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 16 Winter time air leakage condensation potential for Case 5 and Case 11
13 $$
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$ $amp $ $ampamp
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Building Science Corporation +- wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 17 Winter time sheathing relative humidity for Case 8
13131313 13 131313
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13 1313 13$(ampamp+1313 13 1313 13
13 131313amp)1313131313
13131313131313 13 13131313
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13131313 13131313 13
131313131313131313
13131313131313 13
Building Science Corporation - wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 18 Winter air leakage condensation potential for Case 8
223 Summer Inward Vapor Drives
13 13 131313
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1313 1313$13 13$13131313$
1313 13 $13
13131313
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1313 1313$1313
11313$1313$13-$13 131313
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13 1313$1313 1313 13
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Building Science Corporation -+ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 19 Inward vapor drive relative humidity of poly or GWB for Case 1 Case 2 and Case 9
13$13 131313
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13131313131313
Figure 20 Inward vapor drive relative humidity of poly or GWB for Case 3 Case 4 and Case 5
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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Figure 21 Inward vapor drive relative humidity of poly or GWB for Case 4 and Case 10
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 22 Inward vapor drive relative humidity of poly or GWB for Case 8
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Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 23 Inward vapor drive relative humidity of poly or GWB for Cases 5 8 and 11
224 Wall Drying
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Building Science Corporation 02 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 24 Drying Curves for Case 1 and Case 2
13131313 13 13
13 131313
Figure 25 Drying curves for Case 3 Case 4 and Case 5
13 1313
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 26 Drying curves for Case 8
1313 1313$13)1313
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13(13131313 13)13 13 13
13131313131313131313131313 13
1313131313 13131313 131313
131313131313131313131313131313 13
Figure 27 Drying Curves for Case 4 and Case 10 with and without a poly vapor barrier
131313131313 1313 131313
131313 13131313 13 13
Building Science Corporation 30 Forest St Somerville MA 02143
(+ wwwbuildingsciencecom
13 1313
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Figure 28 Drying Curves for Case 5 and Case 11
23 Enclosure Durability
13 13 13
131313
13 131313
13 13 13 1313
13131313 13
1313
1313
24 Buildability
13 1313
13131313 13
1313 13 13131313
1313
13
1313 131313
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
25 Material Use
13131313 1313
13131313$131313
13 1313131313131313131313
13131313131313$1313131313
1313131313
131313$
26 Cost
13 131313131313
1313$1313131313
13131313 1313
13$13amp1313 213
1313 )+$1313 13)-$+
1313$13131313 1313131313
131313$
C Results
1 CASE 1 STANDARD CONSTRUCTION PRACTICE
131313131313--0130(13
13131301313131313133 13$)-2
131313 13131313$
Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 29 Standard construction practice
111 Thermal Control
13) amp( 13
+amp-
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13 $ 13 13
13 13
13(
Building Science Corporation - wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 30 Therm modeling of Case 1 - 2x6 construction
1313 13 13 131313 (-$13
13 131313 1313 13
131313) )13131313131313(-131313
13131313131313131313
13 13131313131313131313)+
13)-13131313131313 13
13
Table 5 Summary of R-value results from Therm modeling for Case 1
1313131313131313131313
131313 131313 13 13
13 1313131313
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13 13 13 13
112 Moisture Control
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30 Forest St Somerville MA 02143
131313
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113 Constructability and Cost
13
amp13
13amp
114 Other Considerations
13
13amp
131+13
amp 13
13amp
12 Case 2 Advanced framing with insulated sheathing
1313
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13amp
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30 Forest St Somerville MA 02143
Figure 31 Advanced framing construction
121 Thermal Control
131313 13$13 1313
1313 13$13$1313 13
$$)amp $$)13$$13 13) 13
1313131313 1313
131313(-(13$amp-( 1313amp
+(13$13$1313$1313amp13
1313131313 1313
131313 1313
13131313131313
131313amp1313 13
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 32 Therm modeling of Case 2 advanced framing with 1 XPS insulated sheathing
amp $ $ 13 + 2 3$$35
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$ amp 2($ )
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Table 6 Summary of R-value results from Therm modeling for Case 2
122 Moisture Control
$
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Building Science Corporation 00 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
131313$ 1313
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2 131313
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123 Constructability and Cost
131313131313
13130$
13-$131313
131313(13
$$13131313
13 1313
124 Other Considerations
amp 1313
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131313$1313 13
1313
13 Case 3 Interior 2x3 horizontal strapping
13 $
13$
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 33 2x6 wall construction with interior strapping
131 Thermal Control
1313 1313131313
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1313131313 1313
131313 13 13131313
1313 1313131313
1313 1313 1313131313
13131313 13
13 13131313$
131313 13
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 34 Therm analysis of horizontally strapped wall
13$13-amp0)132amp 13$
3-1 1amp13 13
amp 13 13amp
Table 7 Calculated R-value of an interior horizontal strapped wall
132 Moisture Control
13
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13 $amp
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30 Forest St Somerville MA 02143
13 13
133 Constructability and Cost
1313$
13 13
1313
134 Other Considerations
13
131313
13
14 Case 4 Double Stud
1313
131313
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 35 Double stud wall
141 Thermal Control
13
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30 Forest St Somerville MA 02143
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Figure 36 Therm model of the double stud wall
Table 8 Calculated R-value of a double stud wall
142 Moisture Control
13131313
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131313
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30 Forest St Somerville MA 02143
13
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13 1313
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143 Constructability and Cost
13
amp 13
144 Other Considerations
13 13
131313
13 1313
15 Case 5 Truss Wall
1313
13 13131313
13 13 13
131313amp
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 37 Truss wall construction
151 Thermal Control
1313
13 13(
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1313
)-13
131313
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13 13
13131313
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 38 Therm results of the truss wall
Table 9 Calculated R-value for truss wall
152 Moisture Control
13
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30 Forest St Somerville MA 02143
153 Constructability and Cost
13
13131313
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154 Other Considerations
13 $$
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16 Case 6 Structural Insulated Panel Systems (SIPs)
131313
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Figure 39 SIPs wall construction
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
161 Thermal Control
13 13
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Figure 40 Therm results of SIPs panel analysis
Table 10 Calculated R-value for a Sips wall system
162 Moisture Control
13 $ $ amp
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amp
-1311) 13 $
)
Building Science Corporation 33 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($$
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163 Constructability and Cost
$amp $$$$ $
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+amp
164 Other Considerations
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17 Case 7 Insulated Concrete Forms (ICFs)
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 41 ICF wall construction
171 Thermal Control
1313
1313 1313
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amp)$)
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 42 Nine inch foam ICF with five inches of EPS
Figure 43 Fifteen inch foam ICF with five inches of EPS
13 13 1313
13 1313131313$13$1313
1313amp1313 13 1313
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172 Moisture Control
1313131313131313 13$amp131313
131313 13amp13
$ 13$1313$13ampamp
13 1313$1313131313
131313amp13
1313131313 13amp
173 Constructability and Cost
13131313 $1313$13$ 13
13 13$1313amp13$13
1313 amp13 13
13 13 1313$
13$13 13$131313
131313 1313 13$amp
174 Other Considerations
13 1313 131313$
13$$131313 1313 13
13amp131313$ 131313
1313 13amp13 131313
Building Science Corporation () wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 1313 13131313 1313 13 13
13 13 1313 13
131313 13131313131313
131313 1313 13 13 1313 13
131313131313 131313
13131313
18 Case 8 Advanced framing with spray foam
13 13 13131313131313
13131313131313 13$
13 $
Figure 44 2x6 wall construction with spray foam insulation
181 Thermal Control
13131313 1313131313 13131313131313
131313131313
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30 Forest St Somerville MA 02143
13amp13 1313$
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Figure 45 Therm modeling of spray foam wall and rim joist
13 amp amp+1+
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Table 11 Therm results of spray foam insulation analysis
182 Moisture Control
13 $
1313 13
131313
13
Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313 13 13
13 13 $ 13
131313 23
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13 13
1313
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1313 13
1313 3
1313$
1313 13 13
13 1313$
(+) 13 13 1313+-
113 13 13 13
-1313+-$
183 Constructability and Cost
13 13 13 13
$13 13
1313 13 13$
184 Other Considerations
1313
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19 Case 9 Hybrid Wall Insulation ndash Flash and Fill
13 $1313
1313 $13
131313$13 131313
13 13$
1313 13 0amp $
13 13
13$ 1313
13 $
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 46 Hybrid wall construction with 2 spray foam and fibrous fill
191 Thermal Control
131313131313
13 1313 13
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13 13 13 13
1313
Building Science Corporation amp$ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 47 Therm analysis of hybrid wall system
Table 12 Calculated R-value for a hybrid wall system
192 Moisture Control
+ amp 13
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193 Constructability and Cost
13131313131313
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1313
194 Other Considerations
1313
1313 1313
1313
Building Science Corporation -+ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 13
13
110 Case 10 Double Stud Wall with Spray Foam
amp 13 13
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131313
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13
Figure 48 Double stud wall with 2 of spray foam and cellulose fill
1101 Thermal Control
$) 13
13(amp() $
13$
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 49 Therm analysis of double stud wall construction with spray foam
Table 13 Calculated whole wall R-value for a double stud wall system with 2rdquo spray foam
1102 Moisture Control
13 13 (13
13 13
13 1313 13
13 13
($$13(amp$$$13
13 1313 1313 13 13
13 13 13 $13 13
1313 amp+ 13
1313 amp1313 13
13 1313 amp
1313 13 13
1103 Constructability and Cost
13131313 13 13
13131313131313
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30 Forest St Somerville MA 02143
1104 Other Considerations
13 13 13 1313
131313(13 131313 1313 13 amp
13 13 (
131313 1313 13 13 13 13
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111 Case 11 Offset Frame Wall with Exterior Spray Foam
131313 1313 13 1313
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13 1313$ 13 13 13(
13 13 13 13 13 13
$ 13 ( 1313 13 131313131313
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13 13 13 )13
13 13 13 13 13 13 13 13
(
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 50 Offset frame wall construction with exterior spray foam
1111 Thermal Control
131313 13 1313131313
1313 131313
13 13 13131313
13 13 13 13 13 13 13
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 51 Therm analysis of an offset truss wall with exterior spray foam
Table 14 Calculated whole wall R-value for an offset framed wall with exterior spray foam
1112 Moisture Control
13
$ 13$
+amp13
+amp$
13 131313
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13 13131313
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1113 Constructability and Cost
13 $13
1313 13 13 $
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30 Forest St Somerville MA 02143
$($( $$
$ $($$($$+
1114 Other Considerations
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112 Case 12 Exterior Insulation Finish System (EIFS)
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Building Science Corporation 25 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 52 Wall construction using the EIFS cladding system
1121 Thermal Control
1313 1313
1313 1313
1313 131313
13 13 $
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 53 Thermal analysis of an EIFS wall system
Table 15 Calculated whole wall R-value for a EIFS wall system with 4rdquo of EPS
1122 Moisture Control
1313131313131313
131313amp1313
13131313
131313amp
13131313131313
13 13 13+ 13amp 131313
1313131313 131313) amp
1123 Constructability and Cost
131313131313
131313amp1313131313amp
131313131313 1313 13
1313amp
1124 Other Considerations
131313131313amp 13
13131313 131313
13amp13$1313131313
1313131313amp 131313131313
131313131313amp
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
D Conclusions
amp 1313
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13131313 1313
1313
Table 16 Summary of all calculated R-values
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1313131313 13
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Building Science Corporation -) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 17 Hours of potential winter time air leakage condensation
13
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131313
13
1313
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1313
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30 Forest St Somerville MA 02143
Table 18 Wall Comparison Chart
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13 13 amp
$13$1313$ 13$
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$ $13$ amp13 $13
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13 $amp13
13$13 13
$ $ 13amp
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30 Forest St Somerville MA 02143
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30 Forest St Somerville MA 02143
E Works Cited
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30 Forest St Somerville MA 02143
Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
Figure 11 Winter air leakage condensation potential for Case 1 and Case 9
13 $1313
13
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Figure 12 Winter time sheathing relative humidity for Case 3 Case 4 and Case 5
13$13 13
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
131313amp13 13 13$
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Figure 13 Winter air leakage condensation potential for Case 3 Case 4 and Case 5
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13$1313$ 1313131313$
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Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 14 Winter air leakage condensation potential for Case 4 and Case 10
13
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 15 Installation of high density spray foam in an Offset Framed Wall in a cold climate
13
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 16 Winter time air leakage condensation potential for Case 5 and Case 11
13 $$
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$ $amp $ $ampamp
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Building Science Corporation +- wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 17 Winter time sheathing relative humidity for Case 8
13131313 13 131313
13131313131313131313 13
13 1313 13$(ampamp+1313 13 1313 13
13 131313amp)1313131313
13131313131313 13 13131313
1313 13 13
13131313 13131313 13
131313131313131313
13131313131313 13
Building Science Corporation - wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 18 Winter air leakage condensation potential for Case 8
223 Summer Inward Vapor Drives
13 13 131313
1313 1313$1313 1313
1313 1313$13 13$13131313$
1313 13 $13
13131313
1313
13 13 131313 131313
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13131313 13 1313$1313
1313 1313$1313
11313$1313$13-$13 131313
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Building Science Corporation -+ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 19 Inward vapor drive relative humidity of poly or GWB for Case 1 Case 2 and Case 9
13$13 131313
1313 131313 13
1313$1313 13
13131313131313
Figure 20 Inward vapor drive relative humidity of poly or GWB for Case 3 Case 4 and Case 5
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313amp$
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Figure 21 Inward vapor drive relative humidity of poly or GWB for Case 4 and Case 10
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 22 Inward vapor drive relative humidity of poly or GWB for Case 8
() 13
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13
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 23 Inward vapor drive relative humidity of poly or GWB for Cases 5 8 and 11
224 Wall Drying
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Building Science Corporation 02 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 24 Drying Curves for Case 1 and Case 2
13131313 13 13
13 131313
Figure 25 Drying curves for Case 3 Case 4 and Case 5
13 1313
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 26 Drying curves for Case 8
1313 1313$13)1313
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13(13131313 13)13 13 13
13131313131313131313131313 13
1313131313 13131313 131313
131313131313131313131313131313 13
Figure 27 Drying Curves for Case 4 and Case 10 with and without a poly vapor barrier
131313131313 1313 131313
131313 13131313 13 13
Building Science Corporation 30 Forest St Somerville MA 02143
(+ wwwbuildingsciencecom
13 1313
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Figure 28 Drying Curves for Case 5 and Case 11
23 Enclosure Durability
13 13 13
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13 131313
13 13 13 1313
13131313 13
1313
1313
24 Buildability
13 1313
13131313 13
1313 13 13131313
1313
13
1313 131313
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
25 Material Use
13131313 1313
13131313$131313
13 1313131313131313131313
13131313131313$1313131313
1313131313
131313$
26 Cost
13 131313131313
1313$1313131313
13131313 1313
13$13amp1313 213
1313 )+$1313 13)-$+
1313$13131313 1313131313
131313$
C Results
1 CASE 1 STANDARD CONSTRUCTION PRACTICE
131313131313--0130(13
13131301313131313133 13$)-2
131313 13131313$
Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 29 Standard construction practice
111 Thermal Control
13) amp( 13
+amp-
13 13 ( ampampampamp(amp13$
13 $ 13 13
13 13
13(
Building Science Corporation - wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 30 Therm modeling of Case 1 - 2x6 construction
1313 13 13 131313 (-$13
13 131313 1313 13
131313) )13131313131313(-131313
13131313131313131313
13 13131313131313131313)+
13)-13131313131313 13
13
Table 5 Summary of R-value results from Therm modeling for Case 1
1313131313131313131313
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112 Moisture Control
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30 Forest St Somerville MA 02143
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113 Constructability and Cost
13
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114 Other Considerations
13
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12 Case 2 Advanced framing with insulated sheathing
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30 Forest St Somerville MA 02143
Figure 31 Advanced framing construction
121 Thermal Control
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1313131313 1313
131313 1313
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30 Forest St Somerville MA 02143
Figure 32 Therm modeling of Case 2 advanced framing with 1 XPS insulated sheathing
amp $ $ 13 + 2 3$$35
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Table 6 Summary of R-value results from Therm modeling for Case 2
122 Moisture Control
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30 Forest St Somerville MA 02143
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123 Constructability and Cost
131313131313
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124 Other Considerations
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13 Case 3 Interior 2x3 horizontal strapping
13 $
13$
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 33 2x6 wall construction with interior strapping
131 Thermal Control
1313 1313131313
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1313131313 1313
131313 13 13131313
1313 1313131313
1313 1313 1313131313
13131313 13
13 13131313$
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 34 Therm analysis of horizontally strapped wall
13$13-amp0)132amp 13$
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Table 7 Calculated R-value of an interior horizontal strapped wall
132 Moisture Control
13
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30 Forest St Somerville MA 02143
13 13
133 Constructability and Cost
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13 13
1313
134 Other Considerations
13
131313
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14 Case 4 Double Stud
1313
131313
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30 Forest St Somerville MA 02143
Figure 35 Double stud wall
141 Thermal Control
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30 Forest St Somerville MA 02143
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Figure 36 Therm model of the double stud wall
Table 8 Calculated R-value of a double stud wall
142 Moisture Control
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30 Forest St Somerville MA 02143
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143 Constructability and Cost
13
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144 Other Considerations
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15 Case 5 Truss Wall
1313
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Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 37 Truss wall construction
151 Thermal Control
1313
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30 Forest St Somerville MA 02143
Figure 38 Therm results of the truss wall
Table 9 Calculated R-value for truss wall
152 Moisture Control
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30 Forest St Somerville MA 02143
153 Constructability and Cost
13
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154 Other Considerations
13 $$
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16 Case 6 Structural Insulated Panel Systems (SIPs)
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Figure 39 SIPs wall construction
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30 Forest St Somerville MA 02143
161 Thermal Control
13 13
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Figure 40 Therm results of SIPs panel analysis
Table 10 Calculated R-value for a Sips wall system
162 Moisture Control
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Building Science Corporation 33 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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163 Constructability and Cost
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164 Other Considerations
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17 Case 7 Insulated Concrete Forms (ICFs)
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30 Forest St Somerville MA 02143
Figure 41 ICF wall construction
171 Thermal Control
1313
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Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 42 Nine inch foam ICF with five inches of EPS
Figure 43 Fifteen inch foam ICF with five inches of EPS
13 13 1313
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172 Moisture Control
1313131313131313 13$amp131313
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13 1313$1313131313
131313amp13
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173 Constructability and Cost
13131313 $1313$13$ 13
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174 Other Considerations
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30 Forest St Somerville MA 02143
13 1313 13131313 1313 13 13
13 13 1313 13
131313 13131313131313
131313 1313 13 13 1313 13
131313131313 131313
13131313
18 Case 8 Advanced framing with spray foam
13 13 13131313131313
13131313131313 13$
13 $
Figure 44 2x6 wall construction with spray foam insulation
181 Thermal Control
13131313 1313131313 13131313131313
131313131313
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30 Forest St Somerville MA 02143
13amp13 1313$
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Figure 45 Therm modeling of spray foam wall and rim joist
13 amp amp+1+
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Table 11 Therm results of spray foam insulation analysis
182 Moisture Control
13 $
1313 13
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Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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113 13 13 13
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183 Constructability and Cost
13 13 13 13
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184 Other Considerations
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19 Case 9 Hybrid Wall Insulation ndash Flash and Fill
13 $1313
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 46 Hybrid wall construction with 2 spray foam and fibrous fill
191 Thermal Control
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Building Science Corporation amp$ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 47 Therm analysis of hybrid wall system
Table 12 Calculated R-value for a hybrid wall system
192 Moisture Control
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193 Constructability and Cost
13131313131313
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194 Other Considerations
1313
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30 Forest St Somerville MA 02143
13 13
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110 Case 10 Double Stud Wall with Spray Foam
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Figure 48 Double stud wall with 2 of spray foam and cellulose fill
1101 Thermal Control
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Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 49 Therm analysis of double stud wall construction with spray foam
Table 13 Calculated whole wall R-value for a double stud wall system with 2rdquo spray foam
1102 Moisture Control
13 13 (13
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1103 Constructability and Cost
13131313 13 13
13131313131313
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30 Forest St Somerville MA 02143
1104 Other Considerations
13 13 13 1313
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111 Case 11 Offset Frame Wall with Exterior Spray Foam
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30 Forest St Somerville MA 02143
Figure 50 Offset frame wall construction with exterior spray foam
1111 Thermal Control
131313 13 1313131313
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13 13 13 13 13 13 13
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 51 Therm analysis of an offset truss wall with exterior spray foam
Table 14 Calculated whole wall R-value for an offset framed wall with exterior spray foam
1112 Moisture Control
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30 Forest St Somerville MA 02143
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1114 Other Considerations
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112 Case 12 Exterior Insulation Finish System (EIFS)
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Building Science Corporation 25 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 52 Wall construction using the EIFS cladding system
1121 Thermal Control
1313 1313
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1313 131313
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Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 53 Thermal analysis of an EIFS wall system
Table 15 Calculated whole wall R-value for a EIFS wall system with 4rdquo of EPS
1122 Moisture Control
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1123 Constructability and Cost
131313131313
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1124 Other Considerations
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30 Forest St Somerville MA 02143
D Conclusions
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Table 16 Summary of all calculated R-values
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30 Forest St Somerville MA 02143
Table 17 Hours of potential winter time air leakage condensation
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30 Forest St Somerville MA 02143
Table 18 Wall Comparison Chart
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30 Forest St Somerville MA 02143
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30 Forest St Somerville MA 02143
E Works Cited
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30 Forest St Somerville MA 02143
Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
131313amp13 13 13$
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Figure 13 Winter air leakage condensation potential for Case 3 Case 4 and Case 5
1313 131313$1313$13
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Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 14 Winter air leakage condensation potential for Case 4 and Case 10
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 15 Installation of high density spray foam in an Offset Framed Wall in a cold climate
13
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30 Forest St Somerville MA 02143
Figure 16 Winter time air leakage condensation potential for Case 5 and Case 11
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30 Forest St Somerville MA 02143
Figure 17 Winter time sheathing relative humidity for Case 8
13131313 13 131313
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Building Science Corporation - wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 18 Winter air leakage condensation potential for Case 8
223 Summer Inward Vapor Drives
13 13 131313
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30 Forest St Somerville MA 02143
Figure 19 Inward vapor drive relative humidity of poly or GWB for Case 1 Case 2 and Case 9
13$13 131313
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Figure 20 Inward vapor drive relative humidity of poly or GWB for Case 3 Case 4 and Case 5
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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Figure 21 Inward vapor drive relative humidity of poly or GWB for Case 4 and Case 10
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30 Forest St Somerville MA 02143
Figure 22 Inward vapor drive relative humidity of poly or GWB for Case 8
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30 Forest St Somerville MA 02143
Figure 23 Inward vapor drive relative humidity of poly or GWB for Cases 5 8 and 11
224 Wall Drying
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Building Science Corporation 02 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 24 Drying Curves for Case 1 and Case 2
13131313 13 13
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Figure 25 Drying curves for Case 3 Case 4 and Case 5
13 1313
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 26 Drying curves for Case 8
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13131313131313131313131313 13
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Figure 27 Drying Curves for Case 4 and Case 10 with and without a poly vapor barrier
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Building Science Corporation 30 Forest St Somerville MA 02143
(+ wwwbuildingsciencecom
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Figure 28 Drying Curves for Case 5 and Case 11
23 Enclosure Durability
13 13 13
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13 13 13 1313
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24 Buildability
13 1313
13131313 13
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1313
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
25 Material Use
13131313 1313
13131313$131313
13 1313131313131313131313
13131313131313$1313131313
1313131313
131313$
26 Cost
13 131313131313
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13131313 1313
13$13amp1313 213
1313 )+$1313 13)-$+
1313$13131313 1313131313
131313$
C Results
1 CASE 1 STANDARD CONSTRUCTION PRACTICE
131313131313--0130(13
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131313 13131313$
Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 29 Standard construction practice
111 Thermal Control
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Building Science Corporation - wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 30 Therm modeling of Case 1 - 2x6 construction
1313 13 13 131313 (-$13
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13131313131313131313
13 13131313131313131313)+
13)-13131313131313 13
13
Table 5 Summary of R-value results from Therm modeling for Case 1
1313131313131313131313
131313 131313 13 13
13 1313131313
1313 1313 131313
13 13 13 13
112 Moisture Control
1313131313 13131313 13
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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113 Constructability and Cost
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114 Other Considerations
13
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12 Case 2 Advanced framing with insulated sheathing
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Building Science Corporation 0 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 31 Advanced framing construction
121 Thermal Control
131313 13$13 1313
1313 13$13$1313 13
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1313131313 1313
131313(-(13$amp-( 1313amp
+(13$13$1313$1313amp13
1313131313 1313
131313 1313
13131313131313
131313amp1313 13
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 32 Therm modeling of Case 2 advanced framing with 1 XPS insulated sheathing
amp $ $ 13 + 2 3$$35
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$ amp 2($ )
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Table 6 Summary of R-value results from Therm modeling for Case 2
122 Moisture Control
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Building Science Corporation 00 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
131313$ 1313
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2 131313
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123 Constructability and Cost
131313131313
13130$
13-$131313
131313(13
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13 1313
124 Other Considerations
amp 1313
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131313$1313 13
1313
13 Case 3 Interior 2x3 horizontal strapping
13 $
13$
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 33 2x6 wall construction with interior strapping
131 Thermal Control
1313 1313131313
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1313131313 1313
131313 13 13131313
1313 1313131313
1313 1313 1313131313
13131313 13
13 13131313$
131313 13
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 34 Therm analysis of horizontally strapped wall
13$13-amp0)132amp 13$
3-1 1amp13 13
amp 13 13amp
Table 7 Calculated R-value of an interior horizontal strapped wall
132 Moisture Control
13
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13 $amp
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30 Forest St Somerville MA 02143
13 13
133 Constructability and Cost
1313$
13 13
1313
134 Other Considerations
13
131313
13
14 Case 4 Double Stud
1313
131313
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 35 Double stud wall
141 Thermal Control
13
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30 Forest St Somerville MA 02143
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Figure 36 Therm model of the double stud wall
Table 8 Calculated R-value of a double stud wall
142 Moisture Control
13131313
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30 Forest St Somerville MA 02143
13
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13 1313
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143 Constructability and Cost
13
amp 13
144 Other Considerations
13 13
131313
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15 Case 5 Truss Wall
1313
13 13131313
13 13 13
131313amp
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 37 Truss wall construction
151 Thermal Control
1313
13 13(
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131313
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13 13
13131313
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 38 Therm results of the truss wall
Table 9 Calculated R-value for truss wall
152 Moisture Control
13
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30 Forest St Somerville MA 02143
153 Constructability and Cost
13
13131313
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154 Other Considerations
13 $$
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16 Case 6 Structural Insulated Panel Systems (SIPs)
131313
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Figure 39 SIPs wall construction
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
161 Thermal Control
13 13
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Figure 40 Therm results of SIPs panel analysis
Table 10 Calculated R-value for a Sips wall system
162 Moisture Control
13 $ $ amp
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amp
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)
Building Science Corporation 33 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($$
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163 Constructability and Cost
$amp $$$$ $
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164 Other Considerations
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17 Case 7 Insulated Concrete Forms (ICFs)
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 41 ICF wall construction
171 Thermal Control
1313
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amp)$)
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 42 Nine inch foam ICF with five inches of EPS
Figure 43 Fifteen inch foam ICF with five inches of EPS
13 13 1313
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172 Moisture Control
1313131313131313 13$amp131313
131313 13amp13
$ 13$1313$13ampamp
13 1313$1313131313
131313amp13
1313131313 13amp
173 Constructability and Cost
13131313 $1313$13$ 13
13 13$1313amp13$13
1313 amp13 13
13 13 1313$
13$13 13$131313
131313 1313 13$amp
174 Other Considerations
13 1313 131313$
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13amp131313$ 131313
1313 13amp13 131313
Building Science Corporation () wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 1313 13131313 1313 13 13
13 13 1313 13
131313 13131313131313
131313 1313 13 13 1313 13
131313131313 131313
13131313
18 Case 8 Advanced framing with spray foam
13 13 13131313131313
13131313131313 13$
13 $
Figure 44 2x6 wall construction with spray foam insulation
181 Thermal Control
13131313 1313131313 13131313131313
131313131313
Building Science Corporation amp( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13amp13 1313$
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Figure 45 Therm modeling of spray foam wall and rim joist
13 amp amp+1+
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Table 11 Therm results of spray foam insulation analysis
182 Moisture Control
13 $
1313 13
131313
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Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313 13 13
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13 13
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1313 13
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(+) 13 13 1313+-
113 13 13 13
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183 Constructability and Cost
13 13 13 13
$13 13
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184 Other Considerations
1313
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19 Case 9 Hybrid Wall Insulation ndash Flash and Fill
13 $1313
1313 $13
131313$13 131313
13 13$
1313 13 0amp $
13 13
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 46 Hybrid wall construction with 2 spray foam and fibrous fill
191 Thermal Control
131313131313
13 1313 13
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13 13 13 13
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Building Science Corporation amp$ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 47 Therm analysis of hybrid wall system
Table 12 Calculated R-value for a hybrid wall system
192 Moisture Control
+ amp 13
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193 Constructability and Cost
13131313131313
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194 Other Considerations
1313
1313 1313
1313
Building Science Corporation -+ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 13
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110 Case 10 Double Stud Wall with Spray Foam
amp 13 13
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13
Figure 48 Double stud wall with 2 of spray foam and cellulose fill
1101 Thermal Control
$) 13
13(amp() $
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Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 49 Therm analysis of double stud wall construction with spray foam
Table 13 Calculated whole wall R-value for a double stud wall system with 2rdquo spray foam
1102 Moisture Control
13 13 (13
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13 1313 13
13 13
($$13(amp$$$13
13 1313 1313 13 13
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1103 Constructability and Cost
13131313 13 13
13131313131313
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30 Forest St Somerville MA 02143
1104 Other Considerations
13 13 13 1313
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111 Case 11 Offset Frame Wall with Exterior Spray Foam
131313 1313 13 1313
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13 13 13 13 13 13
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 50 Offset frame wall construction with exterior spray foam
1111 Thermal Control
131313 13 1313131313
1313 131313
13 13 13131313
13 13 13 13 13 13 13
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 51 Therm analysis of an offset truss wall with exterior spray foam
Table 14 Calculated whole wall R-value for an offset framed wall with exterior spray foam
1112 Moisture Control
13
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13 131313
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1113 Constructability and Cost
13 $13
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30 Forest St Somerville MA 02143
$($( $$
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1114 Other Considerations
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112 Case 12 Exterior Insulation Finish System (EIFS)
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Building Science Corporation 25 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 52 Wall construction using the EIFS cladding system
1121 Thermal Control
1313 1313
1313 1313
1313 131313
13 13 $
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 53 Thermal analysis of an EIFS wall system
Table 15 Calculated whole wall R-value for a EIFS wall system with 4rdquo of EPS
1122 Moisture Control
1313131313131313
131313amp1313
13131313
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1313131313 131313) amp
1123 Constructability and Cost
131313131313
131313amp1313131313amp
131313131313 1313 13
1313amp
1124 Other Considerations
131313131313amp 13
13131313 131313
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1313131313amp 131313131313
131313131313amp
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30 Forest St Somerville MA 02143
D Conclusions
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Table 16 Summary of all calculated R-values
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30 Forest St Somerville MA 02143
Table 17 Hours of potential winter time air leakage condensation
13
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30 Forest St Somerville MA 02143
Table 18 Wall Comparison Chart
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30 Forest St Somerville MA 02143
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30 Forest St Somerville MA 02143
E Works Cited
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30 Forest St Somerville MA 02143
Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
Figure 14 Winter air leakage condensation potential for Case 4 and Case 10
13
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 15 Installation of high density spray foam in an Offset Framed Wall in a cold climate
13
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 16 Winter time air leakage condensation potential for Case 5 and Case 11
13 $$
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Building Science Corporation +- wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 17 Winter time sheathing relative humidity for Case 8
13131313 13 131313
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Building Science Corporation - wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 18 Winter air leakage condensation potential for Case 8
223 Summer Inward Vapor Drives
13 13 131313
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Building Science Corporation -+ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 19 Inward vapor drive relative humidity of poly or GWB for Case 1 Case 2 and Case 9
13$13 131313
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Figure 20 Inward vapor drive relative humidity of poly or GWB for Case 3 Case 4 and Case 5
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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Figure 21 Inward vapor drive relative humidity of poly or GWB for Case 4 and Case 10
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 22 Inward vapor drive relative humidity of poly or GWB for Case 8
() 13
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30 Forest St Somerville MA 02143
Figure 23 Inward vapor drive relative humidity of poly or GWB for Cases 5 8 and 11
224 Wall Drying
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Building Science Corporation 02 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 24 Drying Curves for Case 1 and Case 2
13131313 13 13
13 131313
Figure 25 Drying curves for Case 3 Case 4 and Case 5
13 1313
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131313 13
13
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 26 Drying curves for Case 8
1313 1313$13)1313
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13131313131313131313131313 13
1313131313 13131313 131313
131313131313131313131313131313 13
Figure 27 Drying Curves for Case 4 and Case 10 with and without a poly vapor barrier
131313131313 1313 131313
131313 13131313 13 13
Building Science Corporation 30 Forest St Somerville MA 02143
(+ wwwbuildingsciencecom
13 1313
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Figure 28 Drying Curves for Case 5 and Case 11
23 Enclosure Durability
13 13 13
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13 13 13 1313
13131313 13
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24 Buildability
13 1313
13131313 13
1313 13 13131313
1313
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
25 Material Use
13131313 1313
13131313$131313
13 1313131313131313131313
13131313131313$1313131313
1313131313
131313$
26 Cost
13 131313131313
1313$1313131313
13131313 1313
13$13amp1313 213
1313 )+$1313 13)-$+
1313$13131313 1313131313
131313$
C Results
1 CASE 1 STANDARD CONSTRUCTION PRACTICE
131313131313--0130(13
13131301313131313133 13$)-2
131313 13131313$
Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 29 Standard construction practice
111 Thermal Control
13) amp( 13
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13 13
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Building Science Corporation - wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 30 Therm modeling of Case 1 - 2x6 construction
1313 13 13 131313 (-$13
13 131313 1313 13
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13131313131313131313
13 13131313131313131313)+
13)-13131313131313 13
13
Table 5 Summary of R-value results from Therm modeling for Case 1
1313131313131313131313
131313 131313 13 13
13 1313131313
1313 1313 131313
13 13 13 13
112 Moisture Control
1313131313 13131313 13
++ +13 1313)+ )- 131313
131313131313131313 13 1313131313(amp
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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113 Constructability and Cost
13
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114 Other Considerations
13
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131+13
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12 Case 2 Advanced framing with insulated sheathing
1313
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Building Science Corporation 0 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 31 Advanced framing construction
121 Thermal Control
131313 13$13 1313
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1313131313 1313
131313(-(13$amp-( 1313amp
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1313131313 1313
131313 1313
13131313131313
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Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 32 Therm modeling of Case 2 advanced framing with 1 XPS insulated sheathing
amp $ $ 13 + 2 3$$35
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Table 6 Summary of R-value results from Therm modeling for Case 2
122 Moisture Control
$
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Building Science Corporation 00 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
131313$ 1313
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13
13 1313 13
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2 131313
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123 Constructability and Cost
131313131313
13130$
13-$131313
131313(13
$$13131313
13 1313
124 Other Considerations
amp 1313
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1313$ 13 13
131313$1313 13
1313
13 Case 3 Interior 2x3 horizontal strapping
13 $
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 33 2x6 wall construction with interior strapping
131 Thermal Control
1313 1313131313
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1313131313 1313
131313 13 13131313
1313 1313131313
1313 1313 1313131313
13131313 13
13 13131313$
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 34 Therm analysis of horizontally strapped wall
13$13-amp0)132amp 13$
3-1 1amp13 13
amp 13 13amp
Table 7 Calculated R-value of an interior horizontal strapped wall
132 Moisture Control
13
(1313$amp
$ 13)
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13 $amp
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$ $ 13
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Building Science Corporation 1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 13
133 Constructability and Cost
1313$
13 13
1313
134 Other Considerations
13
131313
13
14 Case 4 Double Stud
1313
131313
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 35 Double stud wall
141 Thermal Control
13
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1313
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13
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1313
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30 Forest St Somerville MA 02143
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amp13 1313$
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Figure 36 Therm model of the double stud wall
Table 8 Calculated R-value of a double stud wall
142 Moisture Control
13131313
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131313$13
131313
13amp 0++ 13$-
1313$
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Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13
13)amp 13
13 1313
13
13
13(13$)- 13)amp
143 Constructability and Cost
13
amp 13
144 Other Considerations
13 13
131313
13 1313
15 Case 5 Truss Wall
1313
13 13131313
13 13 13
131313amp
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 37 Truss wall construction
151 Thermal Control
1313
13 13(
1313)1313
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amp
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1313
)-13
131313
13
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13 13
13131313
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 38 Therm results of the truss wall
Table 9 Calculated R-value for truss wall
152 Moisture Control
13
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1313
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13
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30 Forest St Somerville MA 02143
153 Constructability and Cost
13
13131313
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154 Other Considerations
13 $$
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16 Case 6 Structural Insulated Panel Systems (SIPs)
131313
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amp
Figure 39 SIPs wall construction
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
161 Thermal Control
13 13
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13 $ (
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27( $ amp03)4 13
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Figure 40 Therm results of SIPs panel analysis
Table 10 Calculated R-value for a Sips wall system
162 Moisture Control
13 $ $ amp
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amp
-1311) 13 $
)
Building Science Corporation 33 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($$
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163 Constructability and Cost
$amp $$$$ $
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+amp
164 Other Considerations
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17 Case 7 Insulated Concrete Forms (ICFs)
(amp($
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 41 ICF wall construction
171 Thermal Control
1313
1313 1313
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amp)$)
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 42 Nine inch foam ICF with five inches of EPS
Figure 43 Fifteen inch foam ICF with five inches of EPS
13 13 1313
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172 Moisture Control
1313131313131313 13$amp131313
131313 13amp13
$ 13$1313$13ampamp
13 1313$1313131313
131313amp13
1313131313 13amp
173 Constructability and Cost
13131313 $1313$13$ 13
13 13$1313amp13$13
1313 amp13 13
13 13 1313$
13$13 13$131313
131313 1313 13$amp
174 Other Considerations
13 1313 131313$
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13amp131313$ 131313
1313 13amp13 131313
Building Science Corporation () wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 1313 13131313 1313 13 13
13 13 1313 13
131313 13131313131313
131313 1313 13 13 1313 13
131313131313 131313
13131313
18 Case 8 Advanced framing with spray foam
13 13 13131313131313
13131313131313 13$
13 $
Figure 44 2x6 wall construction with spray foam insulation
181 Thermal Control
13131313 1313131313 13131313131313
131313131313
Building Science Corporation amp( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13amp13 1313$
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13-
Figure 45 Therm modeling of spray foam wall and rim joist
13 amp amp+1+
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Table 11 Therm results of spray foam insulation analysis
182 Moisture Control
13 $
1313 13
131313
13
Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313 13 13
13 13 $ 13
131313 23
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13 13
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1313 13
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1313 13 13
13 1313$
(+) 13 13 1313+-
113 13 13 13
-1313+-$
183 Constructability and Cost
13 13 13 13
$13 13
1313 13 13$
184 Other Considerations
1313
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19 Case 9 Hybrid Wall Insulation ndash Flash and Fill
13 $1313
1313 $13
131313$13 131313
13 13$
1313 13 0amp $
13 13
13$ 1313
13 $
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 46 Hybrid wall construction with 2 spray foam and fibrous fill
191 Thermal Control
131313131313
13 1313 13
$amp $ amp 13
131313$(
13 13 13 13
1313
Building Science Corporation amp$ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 47 Therm analysis of hybrid wall system
Table 12 Calculated R-value for a hybrid wall system
192 Moisture Control
+ amp 13
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13 +(
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193 Constructability and Cost
13131313131313
13
1313
194 Other Considerations
1313
1313 1313
1313
Building Science Corporation -+ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 13
13
110 Case 10 Double Stud Wall with Spray Foam
amp 13 13
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131313
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13
Figure 48 Double stud wall with 2 of spray foam and cellulose fill
1101 Thermal Control
$) 13
13(amp() $
13$
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 49 Therm analysis of double stud wall construction with spray foam
Table 13 Calculated whole wall R-value for a double stud wall system with 2rdquo spray foam
1102 Moisture Control
13 13 (13
13 13
13 1313 13
13 13
($$13(amp$$$13
13 1313 1313 13 13
13 13 13 $13 13
1313 amp+ 13
1313 amp1313 13
13 1313 amp
1313 13 13
1103 Constructability and Cost
13131313 13 13
13131313131313
Building Science Corporation )( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1104 Other Considerations
13 13 13 1313
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13 13 (
131313 1313 13 13 13 13
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111 Case 11 Offset Frame Wall with Exterior Spray Foam
131313 1313 13 1313
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13 1313$ 13 13 13(
13 13 13 13 13 13
$ 13 ( 1313 13 131313131313
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13 13 13 13 13 13 13 13
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 50 Offset frame wall construction with exterior spray foam
1111 Thermal Control
131313 13 1313131313
1313 131313
13 13 13131313
13 13 13 13 13 13 13
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 51 Therm analysis of an offset truss wall with exterior spray foam
Table 14 Calculated whole wall R-value for an offset framed wall with exterior spray foam
1112 Moisture Control
13
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13 131313
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13 13131313
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1113 Constructability and Cost
13 $13
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30 Forest St Somerville MA 02143
$($( $$
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1114 Other Considerations
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112 Case 12 Exterior Insulation Finish System (EIFS)
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Building Science Corporation 25 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 52 Wall construction using the EIFS cladding system
1121 Thermal Control
1313 1313
1313 1313
1313 131313
13 13 $
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 53 Thermal analysis of an EIFS wall system
Table 15 Calculated whole wall R-value for a EIFS wall system with 4rdquo of EPS
1122 Moisture Control
1313131313131313
131313amp1313
13131313
131313amp
13131313131313
13 13 13+ 13amp 131313
1313131313 131313) amp
1123 Constructability and Cost
131313131313
131313amp1313131313amp
131313131313 1313 13
1313amp
1124 Other Considerations
131313131313amp 13
13131313 131313
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1313131313amp 131313131313
131313131313amp
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30 Forest St Somerville MA 02143
D Conclusions
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13131313 1313
1313
Table 16 Summary of all calculated R-values
131313 amp
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1313131313 13
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Building Science Corporation -) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 17 Hours of potential winter time air leakage condensation
13
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30 Forest St Somerville MA 02143
Table 18 Wall Comparison Chart
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$13$1313$ 13$
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30 Forest St Somerville MA 02143
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30 Forest St Somerville MA 02143
E Works Cited
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30 Forest St Somerville MA 02143
Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
Figure 15 Installation of high density spray foam in an Offset Framed Wall in a cold climate
13
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 16 Winter time air leakage condensation potential for Case 5 and Case 11
13 $$
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Building Science Corporation +- wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 17 Winter time sheathing relative humidity for Case 8
13131313 13 131313
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13131313131313 13 13131313
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13131313 13131313 13
131313131313131313
13131313131313 13
Building Science Corporation - wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 18 Winter air leakage condensation potential for Case 8
223 Summer Inward Vapor Drives
13 13 131313
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Building Science Corporation -+ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 19 Inward vapor drive relative humidity of poly or GWB for Case 1 Case 2 and Case 9
13$13 131313
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13131313131313
Figure 20 Inward vapor drive relative humidity of poly or GWB for Case 3 Case 4 and Case 5
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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Figure 21 Inward vapor drive relative humidity of poly or GWB for Case 4 and Case 10
1313
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 22 Inward vapor drive relative humidity of poly or GWB for Case 8
() 13
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Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 23 Inward vapor drive relative humidity of poly or GWB for Cases 5 8 and 11
224 Wall Drying
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Building Science Corporation 02 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 24 Drying Curves for Case 1 and Case 2
13131313 13 13
13 131313
Figure 25 Drying curves for Case 3 Case 4 and Case 5
13 1313
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13
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 26 Drying curves for Case 8
1313 1313$13)1313
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13(13131313 13)13 13 13
13131313131313131313131313 13
1313131313 13131313 131313
131313131313131313131313131313 13
Figure 27 Drying Curves for Case 4 and Case 10 with and without a poly vapor barrier
131313131313 1313 131313
131313 13131313 13 13
Building Science Corporation 30 Forest St Somerville MA 02143
(+ wwwbuildingsciencecom
13 1313
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Figure 28 Drying Curves for Case 5 and Case 11
23 Enclosure Durability
13 13 13
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13 13 13 1313
13131313 13
1313
1313
24 Buildability
13 1313
13131313 13
1313 13 13131313
1313
13
1313 131313
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
25 Material Use
13131313 1313
13131313$131313
13 1313131313131313131313
13131313131313$1313131313
1313131313
131313$
26 Cost
13 131313131313
1313$1313131313
13131313 1313
13$13amp1313 213
1313 )+$1313 13)-$+
1313$13131313 1313131313
131313$
C Results
1 CASE 1 STANDARD CONSTRUCTION PRACTICE
131313131313--0130(13
13131301313131313133 13$)-2
131313 13131313$
Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 29 Standard construction practice
111 Thermal Control
13) amp( 13
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13 $ 13 13
13 13
13(
Building Science Corporation - wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 30 Therm modeling of Case 1 - 2x6 construction
1313 13 13 131313 (-$13
13 131313 1313 13
131313) )13131313131313(-131313
13131313131313131313
13 13131313131313131313)+
13)-13131313131313 13
13
Table 5 Summary of R-value results from Therm modeling for Case 1
1313131313131313131313
131313 131313 13 13
13 1313131313
1313 1313 131313
13 13 13 13
112 Moisture Control
1313131313 13131313 13
++ +13 1313)+ )- 131313
131313131313131313 13 1313131313(amp
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
131313
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113 Constructability and Cost
13
amp13
13amp
114 Other Considerations
13
13amp
131+13
amp 13
13amp
12 Case 2 Advanced framing with insulated sheathing
1313
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Building Science Corporation 0 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 31 Advanced framing construction
121 Thermal Control
131313 13$13 1313
1313 13$13$1313 13
$$)amp $$)13$$13 13) 13
1313131313 1313
131313(-(13$amp-( 1313amp
+(13$13$1313$1313amp13
1313131313 1313
131313 1313
13131313131313
131313amp1313 13
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 32 Therm modeling of Case 2 advanced framing with 1 XPS insulated sheathing
amp $ $ 13 + 2 3$$35
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$ ($ $
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Table 6 Summary of R-value results from Therm modeling for Case 2
122 Moisture Control
$
$$$
( )
$ (-(2( $
3$ 76(23$amp (
$
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(13
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Building Science Corporation 00 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
131313$ 1313
1++-++13
13
13 1313 13
13)-
13
131313 $ )
2 131313
13
123 Constructability and Cost
131313131313
13130$
13-$131313
131313(13
$$13131313
13 1313
124 Other Considerations
amp 1313
1313
1313$ 13 13
131313$1313 13
1313
13 Case 3 Interior 2x3 horizontal strapping
13 $
13$
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 33 2x6 wall construction with interior strapping
131 Thermal Control
1313 1313131313
1313131313 amp
1313131313 1313
131313 13 13131313
1313 1313131313
1313 1313 1313131313
13131313 13
13 13131313$
131313 13
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 34 Therm analysis of horizontally strapped wall
13$13-amp0)132amp 13$
3-1 1amp13 13
amp 13 13amp
Table 7 Calculated R-value of an interior horizontal strapped wall
132 Moisture Control
13
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$amp
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13 $amp
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30 Forest St Somerville MA 02143
13 13
133 Constructability and Cost
1313$
13 13
1313
134 Other Considerations
13
131313
13
14 Case 4 Double Stud
1313
131313
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 35 Double stud wall
141 Thermal Control
13
1313) 13
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1313
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13
13
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13 13
$ 13
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30 Forest St Somerville MA 02143
13$131313
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Figure 36 Therm model of the double stud wall
Table 8 Calculated R-value of a double stud wall
142 Moisture Control
13131313
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amp13 $$13
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131313
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Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13
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13 1313
13
13
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143 Constructability and Cost
13
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144 Other Considerations
13 13
131313
13 1313
15 Case 5 Truss Wall
1313
13 13131313
13 13 13
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Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 37 Truss wall construction
151 Thermal Control
1313
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13131313
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 38 Therm results of the truss wall
Table 9 Calculated R-value for truss wall
152 Moisture Control
13
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30 Forest St Somerville MA 02143
153 Constructability and Cost
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154 Other Considerations
13 $$
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16 Case 6 Structural Insulated Panel Systems (SIPs)
131313
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Figure 39 SIPs wall construction
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
161 Thermal Control
13 13
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Figure 40 Therm results of SIPs panel analysis
Table 10 Calculated R-value for a Sips wall system
162 Moisture Control
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Building Science Corporation 33 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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163 Constructability and Cost
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164 Other Considerations
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17 Case 7 Insulated Concrete Forms (ICFs)
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 41 ICF wall construction
171 Thermal Control
1313
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Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 42 Nine inch foam ICF with five inches of EPS
Figure 43 Fifteen inch foam ICF with five inches of EPS
13 13 1313
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172 Moisture Control
1313131313131313 13$amp131313
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173 Constructability and Cost
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174 Other Considerations
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30 Forest St Somerville MA 02143
13 1313 13131313 1313 13 13
13 13 1313 13
131313 13131313131313
131313 1313 13 13 1313 13
131313131313 131313
13131313
18 Case 8 Advanced framing with spray foam
13 13 13131313131313
13131313131313 13$
13 $
Figure 44 2x6 wall construction with spray foam insulation
181 Thermal Control
13131313 1313131313 13131313131313
131313131313
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30 Forest St Somerville MA 02143
13amp13 1313$
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Figure 45 Therm modeling of spray foam wall and rim joist
13 amp amp+1+
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Table 11 Therm results of spray foam insulation analysis
182 Moisture Control
13 $
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30 Forest St Somerville MA 02143
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113 13 13 13
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183 Constructability and Cost
13 13 13 13
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184 Other Considerations
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19 Case 9 Hybrid Wall Insulation ndash Flash and Fill
13 $1313
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13 13$
1313 13 0amp $
13 13
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 46 Hybrid wall construction with 2 spray foam and fibrous fill
191 Thermal Control
131313131313
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Building Science Corporation amp$ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 47 Therm analysis of hybrid wall system
Table 12 Calculated R-value for a hybrid wall system
192 Moisture Control
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193 Constructability and Cost
13131313131313
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194 Other Considerations
1313
1313 1313
1313
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30 Forest St Somerville MA 02143
13 13
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110 Case 10 Double Stud Wall with Spray Foam
amp 13 13
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Figure 48 Double stud wall with 2 of spray foam and cellulose fill
1101 Thermal Control
$) 13
13(amp() $
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Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 49 Therm analysis of double stud wall construction with spray foam
Table 13 Calculated whole wall R-value for a double stud wall system with 2rdquo spray foam
1102 Moisture Control
13 13 (13
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1103 Constructability and Cost
13131313 13 13
13131313131313
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30 Forest St Somerville MA 02143
1104 Other Considerations
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111 Case 11 Offset Frame Wall with Exterior Spray Foam
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30 Forest St Somerville MA 02143
Figure 50 Offset frame wall construction with exterior spray foam
1111 Thermal Control
131313 13 1313131313
1313 131313
13 13 13131313
13 13 13 13 13 13 13
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 51 Therm analysis of an offset truss wall with exterior spray foam
Table 14 Calculated whole wall R-value for an offset framed wall with exterior spray foam
1112 Moisture Control
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30 Forest St Somerville MA 02143
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1114 Other Considerations
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112 Case 12 Exterior Insulation Finish System (EIFS)
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Building Science Corporation 25 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 52 Wall construction using the EIFS cladding system
1121 Thermal Control
1313 1313
1313 1313
1313 131313
13 13 $
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 53 Thermal analysis of an EIFS wall system
Table 15 Calculated whole wall R-value for a EIFS wall system with 4rdquo of EPS
1122 Moisture Control
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1123 Constructability and Cost
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1124 Other Considerations
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30 Forest St Somerville MA 02143
D Conclusions
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Table 16 Summary of all calculated R-values
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30 Forest St Somerville MA 02143
Table 17 Hours of potential winter time air leakage condensation
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30 Forest St Somerville MA 02143
Table 18 Wall Comparison Chart
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30 Forest St Somerville MA 02143
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30 Forest St Somerville MA 02143
E Works Cited
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30 Forest St Somerville MA 02143
Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
Figure 16 Winter time air leakage condensation potential for Case 5 and Case 11
13 $$
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Building Science Corporation +- wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 17 Winter time sheathing relative humidity for Case 8
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131313131313131313
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Building Science Corporation - wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 18 Winter air leakage condensation potential for Case 8
223 Summer Inward Vapor Drives
13 13 131313
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Building Science Corporation -+ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 19 Inward vapor drive relative humidity of poly or GWB for Case 1 Case 2 and Case 9
13$13 131313
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Figure 20 Inward vapor drive relative humidity of poly or GWB for Case 3 Case 4 and Case 5
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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Figure 21 Inward vapor drive relative humidity of poly or GWB for Case 4 and Case 10
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 22 Inward vapor drive relative humidity of poly or GWB for Case 8
() 13
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Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 23 Inward vapor drive relative humidity of poly or GWB for Cases 5 8 and 11
224 Wall Drying
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Building Science Corporation 02 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 24 Drying Curves for Case 1 and Case 2
13131313 13 13
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Figure 25 Drying curves for Case 3 Case 4 and Case 5
13 1313
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 26 Drying curves for Case 8
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1313131313 13131313 131313
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Figure 27 Drying Curves for Case 4 and Case 10 with and without a poly vapor barrier
131313131313 1313 131313
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Building Science Corporation 30 Forest St Somerville MA 02143
(+ wwwbuildingsciencecom
13 1313
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Figure 28 Drying Curves for Case 5 and Case 11
23 Enclosure Durability
13 13 13
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24 Buildability
13 1313
13131313 13
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
25 Material Use
13131313 1313
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13 1313131313131313131313
13131313131313$1313131313
1313131313
131313$
26 Cost
13 131313131313
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13131313 1313
13$13amp1313 213
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1313$13131313 1313131313
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C Results
1 CASE 1 STANDARD CONSTRUCTION PRACTICE
131313131313--0130(13
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Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 29 Standard construction practice
111 Thermal Control
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Building Science Corporation - wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 30 Therm modeling of Case 1 - 2x6 construction
1313 13 13 131313 (-$13
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13
Table 5 Summary of R-value results from Therm modeling for Case 1
1313131313131313131313
131313 131313 13 13
13 1313131313
1313 1313 131313
13 13 13 13
112 Moisture Control
1313131313 13131313 13
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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113 Constructability and Cost
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114 Other Considerations
13
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12 Case 2 Advanced framing with insulated sheathing
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Building Science Corporation 0 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 31 Advanced framing construction
121 Thermal Control
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1313131313 1313
131313(-(13$amp-( 1313amp
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1313131313 1313
131313 1313
13131313131313
131313amp1313 13
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 32 Therm modeling of Case 2 advanced framing with 1 XPS insulated sheathing
amp $ $ 13 + 2 3$$35
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Table 6 Summary of R-value results from Therm modeling for Case 2
122 Moisture Control
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Building Science Corporation 00 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
131313$ 1313
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2 131313
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123 Constructability and Cost
131313131313
13130$
13-$131313
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13 1313
124 Other Considerations
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131313$1313 13
1313
13 Case 3 Interior 2x3 horizontal strapping
13 $
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 33 2x6 wall construction with interior strapping
131 Thermal Control
1313 1313131313
1313131313 amp
1313131313 1313
131313 13 13131313
1313 1313131313
1313 1313 1313131313
13131313 13
13 13131313$
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 34 Therm analysis of horizontally strapped wall
13$13-amp0)132amp 13$
3-1 1amp13 13
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Table 7 Calculated R-value of an interior horizontal strapped wall
132 Moisture Control
13
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13 $amp
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30 Forest St Somerville MA 02143
13 13
133 Constructability and Cost
1313$
13 13
1313
134 Other Considerations
13
131313
13
14 Case 4 Double Stud
1313
131313
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 35 Double stud wall
141 Thermal Control
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30 Forest St Somerville MA 02143
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Figure 36 Therm model of the double stud wall
Table 8 Calculated R-value of a double stud wall
142 Moisture Control
13131313
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30 Forest St Somerville MA 02143
13
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13 1313
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143 Constructability and Cost
13
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144 Other Considerations
13 13
131313
13 1313
15 Case 5 Truss Wall
1313
13 13131313
13 13 13
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Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 37 Truss wall construction
151 Thermal Control
1313
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 38 Therm results of the truss wall
Table 9 Calculated R-value for truss wall
152 Moisture Control
13
1313
13 1313
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30 Forest St Somerville MA 02143
153 Constructability and Cost
13
13131313
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154 Other Considerations
13 $$
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16 Case 6 Structural Insulated Panel Systems (SIPs)
131313
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Figure 39 SIPs wall construction
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
161 Thermal Control
13 13
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Figure 40 Therm results of SIPs panel analysis
Table 10 Calculated R-value for a Sips wall system
162 Moisture Control
13 $ $ amp
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Building Science Corporation 33 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($$
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163 Constructability and Cost
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164 Other Considerations
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17 Case 7 Insulated Concrete Forms (ICFs)
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 41 ICF wall construction
171 Thermal Control
1313
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Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 42 Nine inch foam ICF with five inches of EPS
Figure 43 Fifteen inch foam ICF with five inches of EPS
13 13 1313
13 1313131313$13$1313
1313amp1313 13 1313
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172 Moisture Control
1313131313131313 13$amp131313
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173 Constructability and Cost
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174 Other Considerations
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30 Forest St Somerville MA 02143
13 1313 13131313 1313 13 13
13 13 1313 13
131313 13131313131313
131313 1313 13 13 1313 13
131313131313 131313
13131313
18 Case 8 Advanced framing with spray foam
13 13 13131313131313
13131313131313 13$
13 $
Figure 44 2x6 wall construction with spray foam insulation
181 Thermal Control
13131313 1313131313 13131313131313
131313131313
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30 Forest St Somerville MA 02143
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Figure 45 Therm modeling of spray foam wall and rim joist
13 amp amp+1+
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Table 11 Therm results of spray foam insulation analysis
182 Moisture Control
13 $
1313 13
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30 Forest St Somerville MA 02143
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113 13 13 13
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183 Constructability and Cost
13 13 13 13
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184 Other Considerations
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19 Case 9 Hybrid Wall Insulation ndash Flash and Fill
13 $1313
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13 13
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 46 Hybrid wall construction with 2 spray foam and fibrous fill
191 Thermal Control
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30 Forest St Somerville MA 02143
Figure 47 Therm analysis of hybrid wall system
Table 12 Calculated R-value for a hybrid wall system
192 Moisture Control
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193 Constructability and Cost
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194 Other Considerations
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30 Forest St Somerville MA 02143
13 13
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110 Case 10 Double Stud Wall with Spray Foam
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Figure 48 Double stud wall with 2 of spray foam and cellulose fill
1101 Thermal Control
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13(amp() $
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Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 49 Therm analysis of double stud wall construction with spray foam
Table 13 Calculated whole wall R-value for a double stud wall system with 2rdquo spray foam
1102 Moisture Control
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1103 Constructability and Cost
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30 Forest St Somerville MA 02143
1104 Other Considerations
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111 Case 11 Offset Frame Wall with Exterior Spray Foam
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30 Forest St Somerville MA 02143
Figure 50 Offset frame wall construction with exterior spray foam
1111 Thermal Control
131313 13 1313131313
1313 131313
13 13 13131313
13 13 13 13 13 13 13
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30 Forest St Somerville MA 02143
Figure 51 Therm analysis of an offset truss wall with exterior spray foam
Table 14 Calculated whole wall R-value for an offset framed wall with exterior spray foam
1112 Moisture Control
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30 Forest St Somerville MA 02143
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1114 Other Considerations
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112 Case 12 Exterior Insulation Finish System (EIFS)
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30 Forest St Somerville MA 02143
Figure 52 Wall construction using the EIFS cladding system
1121 Thermal Control
1313 1313
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13 13 $
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 53 Thermal analysis of an EIFS wall system
Table 15 Calculated whole wall R-value for a EIFS wall system with 4rdquo of EPS
1122 Moisture Control
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1124 Other Considerations
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30 Forest St Somerville MA 02143
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30 Forest St Somerville MA 02143
Table 17 Hours of potential winter time air leakage condensation
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30 Forest St Somerville MA 02143
Table 18 Wall Comparison Chart
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30 Forest St Somerville MA 02143
Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
Figure 17 Winter time sheathing relative humidity for Case 8
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Building Science Corporation - wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 18 Winter air leakage condensation potential for Case 8
223 Summer Inward Vapor Drives
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30 Forest St Somerville MA 02143
Figure 19 Inward vapor drive relative humidity of poly or GWB for Case 1 Case 2 and Case 9
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Figure 20 Inward vapor drive relative humidity of poly or GWB for Case 3 Case 4 and Case 5
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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Figure 21 Inward vapor drive relative humidity of poly or GWB for Case 4 and Case 10
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30 Forest St Somerville MA 02143
Figure 22 Inward vapor drive relative humidity of poly or GWB for Case 8
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30 Forest St Somerville MA 02143
Figure 23 Inward vapor drive relative humidity of poly or GWB for Cases 5 8 and 11
224 Wall Drying
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Building Science Corporation 02 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 24 Drying Curves for Case 1 and Case 2
13131313 13 13
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Figure 25 Drying curves for Case 3 Case 4 and Case 5
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 26 Drying curves for Case 8
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Figure 27 Drying Curves for Case 4 and Case 10 with and without a poly vapor barrier
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Building Science Corporation 30 Forest St Somerville MA 02143
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Figure 28 Drying Curves for Case 5 and Case 11
23 Enclosure Durability
13 13 13
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24 Buildability
13 1313
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
25 Material Use
13131313 1313
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1313131313
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26 Cost
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C Results
1 CASE 1 STANDARD CONSTRUCTION PRACTICE
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Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 29 Standard construction practice
111 Thermal Control
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Building Science Corporation - wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 30 Therm modeling of Case 1 - 2x6 construction
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Table 5 Summary of R-value results from Therm modeling for Case 1
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112 Moisture Control
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30 Forest St Somerville MA 02143
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113 Constructability and Cost
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114 Other Considerations
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30 Forest St Somerville MA 02143
Figure 31 Advanced framing construction
121 Thermal Control
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30 Forest St Somerville MA 02143
Figure 32 Therm modeling of Case 2 advanced framing with 1 XPS insulated sheathing
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122 Moisture Control
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30 Forest St Somerville MA 02143
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123 Constructability and Cost
131313131313
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124 Other Considerations
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13 Case 3 Interior 2x3 horizontal strapping
13 $
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 33 2x6 wall construction with interior strapping
131 Thermal Control
1313 1313131313
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1313131313 1313
131313 13 13131313
1313 1313131313
1313 1313 1313131313
13131313 13
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 34 Therm analysis of horizontally strapped wall
13$13-amp0)132amp 13$
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Table 7 Calculated R-value of an interior horizontal strapped wall
132 Moisture Control
13
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30 Forest St Somerville MA 02143
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133 Constructability and Cost
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134 Other Considerations
13
131313
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14 Case 4 Double Stud
1313
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30 Forest St Somerville MA 02143
Figure 35 Double stud wall
141 Thermal Control
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30 Forest St Somerville MA 02143
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Figure 36 Therm model of the double stud wall
Table 8 Calculated R-value of a double stud wall
142 Moisture Control
13131313
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30 Forest St Somerville MA 02143
13
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143 Constructability and Cost
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144 Other Considerations
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15 Case 5 Truss Wall
1313
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13 13 13
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Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 37 Truss wall construction
151 Thermal Control
1313
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30 Forest St Somerville MA 02143
Figure 38 Therm results of the truss wall
Table 9 Calculated R-value for truss wall
152 Moisture Control
13
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30 Forest St Somerville MA 02143
153 Constructability and Cost
13
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154 Other Considerations
13 $$
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16 Case 6 Structural Insulated Panel Systems (SIPs)
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Figure 39 SIPs wall construction
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
161 Thermal Control
13 13
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Figure 40 Therm results of SIPs panel analysis
Table 10 Calculated R-value for a Sips wall system
162 Moisture Control
13 $ $ amp
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Building Science Corporation 33 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($$
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163 Constructability and Cost
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164 Other Considerations
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17 Case 7 Insulated Concrete Forms (ICFs)
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 41 ICF wall construction
171 Thermal Control
1313
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Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 42 Nine inch foam ICF with five inches of EPS
Figure 43 Fifteen inch foam ICF with five inches of EPS
13 13 1313
13 1313131313$13$1313
1313amp1313 13 1313
13131313$amp
172 Moisture Control
1313131313131313 13$amp131313
131313 13amp13
$ 13$1313$13ampamp
13 1313$1313131313
131313amp13
1313131313 13amp
173 Constructability and Cost
13131313 $1313$13$ 13
13 13$1313amp13$13
1313 amp13 13
13 13 1313$
13$13 13$131313
131313 1313 13$amp
174 Other Considerations
13 1313 131313$
13$$131313 1313 13
13amp131313$ 131313
1313 13amp13 131313
Building Science Corporation () wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 1313 13131313 1313 13 13
13 13 1313 13
131313 13131313131313
131313 1313 13 13 1313 13
131313131313 131313
13131313
18 Case 8 Advanced framing with spray foam
13 13 13131313131313
13131313131313 13$
13 $
Figure 44 2x6 wall construction with spray foam insulation
181 Thermal Control
13131313 1313131313 13131313131313
131313131313
Building Science Corporation amp( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13amp13 1313$
13amp
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13-
Figure 45 Therm modeling of spray foam wall and rim joist
13 amp amp+1+
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Table 11 Therm results of spray foam insulation analysis
182 Moisture Control
13 $
1313 13
131313
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Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313 13 13
13 13 $ 13
131313 23
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1313 13 13
13 1313$
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113 13 13 13
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183 Constructability and Cost
13 13 13 13
$13 13
1313 13 13$
184 Other Considerations
1313
$ 1313
13 1313$
19 Case 9 Hybrid Wall Insulation ndash Flash and Fill
13 $1313
1313 $13
131313$13 131313
13 13$
1313 13 0amp $
13 13
13$ 1313
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 46 Hybrid wall construction with 2 spray foam and fibrous fill
191 Thermal Control
131313131313
13 1313 13
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13 13 13 13
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30 Forest St Somerville MA 02143
Figure 47 Therm analysis of hybrid wall system
Table 12 Calculated R-value for a hybrid wall system
192 Moisture Control
+ amp 13
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193 Constructability and Cost
13131313131313
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194 Other Considerations
1313
1313 1313
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Building Science Corporation -+ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 13
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110 Case 10 Double Stud Wall with Spray Foam
amp 13 13
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131313
13
13 131313
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13
Figure 48 Double stud wall with 2 of spray foam and cellulose fill
1101 Thermal Control
$) 13
13(amp() $
13$
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 49 Therm analysis of double stud wall construction with spray foam
Table 13 Calculated whole wall R-value for a double stud wall system with 2rdquo spray foam
1102 Moisture Control
13 13 (13
13 13
13 1313 13
13 13
($$13(amp$$$13
13 1313 1313 13 13
13 13 13 $13 13
1313 amp+ 13
1313 amp1313 13
13 1313 amp
1313 13 13
1103 Constructability and Cost
13131313 13 13
13131313131313
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30 Forest St Somerville MA 02143
1104 Other Considerations
13 13 13 1313
131313(13 131313 1313 13 amp
13 13 (
131313 1313 13 13 13 13
13 (
111 Case 11 Offset Frame Wall with Exterior Spray Foam
131313 1313 13 1313
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13 1313$ 13 13 13(
13 13 13 13 13 13
$ 13 ( 1313 13 131313131313
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1313 ( 1313 13 13
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131313 1313 1313(13 13
13 13 13 )13
13 13 13 13 13 13 13 13
(
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 50 Offset frame wall construction with exterior spray foam
1111 Thermal Control
131313 13 1313131313
1313 131313
13 13 13131313
13 13 13 13 13 13 13
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 51 Therm analysis of an offset truss wall with exterior spray foam
Table 14 Calculated whole wall R-value for an offset framed wall with exterior spray foam
1112 Moisture Control
13
$ 13$
+amp13
+amp$
13 131313
1313 ()amp$13
13 13131313
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1113 Constructability and Cost
13 $13
1313 13 13 $
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30 Forest St Somerville MA 02143
$($( $$
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1114 Other Considerations
$$amp$(amp$+
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112 Case 12 Exterior Insulation Finish System (EIFS)
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Building Science Corporation 25 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 52 Wall construction using the EIFS cladding system
1121 Thermal Control
1313 1313
1313 1313
1313 131313
13 13 $
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 53 Thermal analysis of an EIFS wall system
Table 15 Calculated whole wall R-value for a EIFS wall system with 4rdquo of EPS
1122 Moisture Control
1313131313131313
131313amp1313
13131313
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13131313131313
13 13 13+ 13amp 131313
1313131313 131313) amp
1123 Constructability and Cost
131313131313
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131313131313 1313 13
1313amp
1124 Other Considerations
131313131313amp 13
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1313131313amp 131313131313
131313131313amp
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30 Forest St Somerville MA 02143
D Conclusions
amp 1313
)- 13$13
13131313 1313
1313
Table 16 Summary of all calculated R-values
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30 Forest St Somerville MA 02143
Table 17 Hours of potential winter time air leakage condensation
13
) 1313amp$13
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1313
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1313
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30 Forest St Somerville MA 02143
Table 18 Wall Comparison Chart
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13 $amp13
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30 Forest St Somerville MA 02143
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30 Forest St Somerville MA 02143
E Works Cited
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30 Forest St Somerville MA 02143
Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
Figure 18 Winter air leakage condensation potential for Case 8
223 Summer Inward Vapor Drives
13 13 131313
1313 1313$1313 1313
1313 1313$13 13$13131313$
1313 13 $13
13131313
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1313131313
1313 13 13 13)13$$13
13131313 13 1313$1313
1313 1313$1313
11313$1313$13-$13 131313
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13 131313 131313amp
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Building Science Corporation -+ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 19 Inward vapor drive relative humidity of poly or GWB for Case 1 Case 2 and Case 9
13$13 131313
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13131313131313
Figure 20 Inward vapor drive relative humidity of poly or GWB for Case 3 Case 4 and Case 5
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313amp$
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Figure 21 Inward vapor drive relative humidity of poly or GWB for Case 4 and Case 10
1313
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 22 Inward vapor drive relative humidity of poly or GWB for Case 8
() 13
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13
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 23 Inward vapor drive relative humidity of poly or GWB for Cases 5 8 and 11
224 Wall Drying
-
+031
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13 amp
Building Science Corporation 02 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 24 Drying Curves for Case 1 and Case 2
13131313 13 13
13 131313
Figure 25 Drying curves for Case 3 Case 4 and Case 5
13 1313
13131313131313
131313 13
13
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 26 Drying curves for Case 8
1313 1313$13)1313
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13(13131313 13)13 13 13
13131313131313131313131313 13
1313131313 13131313 131313
131313131313131313131313131313 13
Figure 27 Drying Curves for Case 4 and Case 10 with and without a poly vapor barrier
131313131313 1313 131313
131313 13131313 13 13
Building Science Corporation 30 Forest St Somerville MA 02143
(+ wwwbuildingsciencecom
13 1313
1313 131313
$$ 1313
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131313 1313
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Figure 28 Drying Curves for Case 5 and Case 11
23 Enclosure Durability
13 13 13
131313
13 131313
13 13 13 1313
13131313 13
1313
1313
24 Buildability
13 1313
13131313 13
1313 13 13131313
1313
13
1313 131313
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
25 Material Use
13131313 1313
13131313$131313
13 1313131313131313131313
13131313131313$1313131313
1313131313
131313$
26 Cost
13 131313131313
1313$1313131313
13131313 1313
13$13amp1313 213
1313 )+$1313 13)-$+
1313$13131313 1313131313
131313$
C Results
1 CASE 1 STANDARD CONSTRUCTION PRACTICE
131313131313--0130(13
13131301313131313133 13$)-2
131313 13131313$
Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 29 Standard construction practice
111 Thermal Control
13) amp( 13
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13 13 ( ampampampamp(amp13$
13 $ 13 13
13 13
13(
Building Science Corporation - wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 30 Therm modeling of Case 1 - 2x6 construction
1313 13 13 131313 (-$13
13 131313 1313 13
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13131313131313131313
13 13131313131313131313)+
13)-13131313131313 13
13
Table 5 Summary of R-value results from Therm modeling for Case 1
1313131313131313131313
131313 131313 13 13
13 1313131313
1313 1313 131313
13 13 13 13
112 Moisture Control
1313131313 13131313 13
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
131313
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113 Constructability and Cost
13
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114 Other Considerations
13
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131+13
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12 Case 2 Advanced framing with insulated sheathing
1313
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Building Science Corporation 0 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 31 Advanced framing construction
121 Thermal Control
131313 13$13 1313
1313 13$13$1313 13
$$)amp $$)13$$13 13) 13
1313131313 1313
131313(-(13$amp-( 1313amp
+(13$13$1313$1313amp13
1313131313 1313
131313 1313
13131313131313
131313amp1313 13
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 32 Therm modeling of Case 2 advanced framing with 1 XPS insulated sheathing
amp $ $ 13 + 2 3$$35
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Table 6 Summary of R-value results from Therm modeling for Case 2
122 Moisture Control
$
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Building Science Corporation 00 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
131313$ 1313
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13 1313 13
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2 131313
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123 Constructability and Cost
131313131313
13130$
13-$131313
131313(13
$$13131313
13 1313
124 Other Considerations
amp 1313
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131313$1313 13
1313
13 Case 3 Interior 2x3 horizontal strapping
13 $
13$
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 33 2x6 wall construction with interior strapping
131 Thermal Control
1313 1313131313
1313131313 amp
1313131313 1313
131313 13 13131313
1313 1313131313
1313 1313 1313131313
13131313 13
13 13131313$
131313 13
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 34 Therm analysis of horizontally strapped wall
13$13-amp0)132amp 13$
3-1 1amp13 13
amp 13 13amp
Table 7 Calculated R-value of an interior horizontal strapped wall
132 Moisture Control
13
(1313$amp
$ 13)
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$amp
13$ 13$
13 $amp
$
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Building Science Corporation 1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 13
133 Constructability and Cost
1313$
13 13
1313
134 Other Considerations
13
131313
13
14 Case 4 Double Stud
1313
131313
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 35 Double stud wall
141 Thermal Control
13
1313) 13
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1313
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13
13
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13 13
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30 Forest St Somerville MA 02143
13$131313
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Figure 36 Therm model of the double stud wall
Table 8 Calculated R-value of a double stud wall
142 Moisture Control
13131313
01313 13
amp13 $$13
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131313$13
131313
13amp 0++ 13$-
1313$
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Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13
13)amp 13
13 1313
13
13
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143 Constructability and Cost
13
amp 13
144 Other Considerations
13 13
131313
13 1313
15 Case 5 Truss Wall
1313
13 13131313
13 13 13
131313amp
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 37 Truss wall construction
151 Thermal Control
1313
13 13(
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13
1313
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131313
13
13 $)
13 13
13131313
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 38 Therm results of the truss wall
Table 9 Calculated R-value for truss wall
152 Moisture Control
13
1313
13 1313
13amp(
131313
13 13
1313
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13
13
13 13$13
13
13
1313
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Building Science Corporation amp$ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
153 Constructability and Cost
13
13131313
13
13+($13
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$ 13
154 Other Considerations
13 $$
1313amp
)
16 Case 6 Structural Insulated Panel Systems (SIPs)
131313
13 13$13 13
amp
Figure 39 SIPs wall construction
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
161 Thermal Control
13 13
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)13 $$
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13 $ (
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27( $ amp03)4 13
)$ amp02)5
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Figure 40 Therm results of SIPs panel analysis
Table 10 Calculated R-value for a Sips wall system
162 Moisture Control
13 $ $ amp
$ ) ( 13
amp
-1311) 13 $
)
Building Science Corporation 33 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($$
amp$$+$($
163 Constructability and Cost
$amp $$$$ $
()$$(($(
+amp
164 Other Considerations
()($$$((
$) $ $$
$)$amp$amp($
$)
$$)($amp
amp)ampamp13+$$$
)(ampamp13+$(amp
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- +13amp()$)$
)($
17 Case 7 Insulated Concrete Forms (ICFs)
(amp($
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 41 ICF wall construction
171 Thermal Control
1313
1313 1313
131313 (
+$)$13 13($
amp)$)
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 42 Nine inch foam ICF with five inches of EPS
Figure 43 Fifteen inch foam ICF with five inches of EPS
13 13 1313
13 1313131313$13$1313
1313amp1313 13 1313
13131313$amp
172 Moisture Control
1313131313131313 13$amp131313
131313 13amp13
$ 13$1313$13ampamp
13 1313$1313131313
131313amp13
1313131313 13amp
173 Constructability and Cost
13131313 $1313$13$ 13
13 13$1313amp13$13
1313 amp13 13
13 13 1313$
13$13 13$131313
131313 1313 13$amp
174 Other Considerations
13 1313 131313$
13$$131313 1313 13
13amp131313$ 131313
1313 13amp13 131313
Building Science Corporation () wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 1313 13131313 1313 13 13
13 13 1313 13
131313 13131313131313
131313 1313 13 13 1313 13
131313131313 131313
13131313
18 Case 8 Advanced framing with spray foam
13 13 13131313131313
13131313131313 13$
13 $
Figure 44 2x6 wall construction with spray foam insulation
181 Thermal Control
13131313 1313131313 13131313131313
131313131313
Building Science Corporation amp( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13amp13 1313$
13amp
0$+ $0
13$
$131313
13131313$1313
13-
Figure 45 Therm modeling of spray foam wall and rim joist
13 amp amp+1+
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13-amp(1+)13
amp 131
amp
Table 11 Therm results of spray foam insulation analysis
182 Moisture Control
13 $
1313 13
131313
13
Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313 13 13
13 13 $ 13
131313 23
(+-)$
13 13
1313
13 (+)$
1313 13
1313 3
1313$
1313 13 13
13 1313$
(+) 13 13 1313+-
113 13 13 13
-1313+-$
183 Constructability and Cost
13 13 13 13
$13 13
1313 13 13$
184 Other Considerations
1313
$ 1313
13 1313$
19 Case 9 Hybrid Wall Insulation ndash Flash and Fill
13 $1313
1313 $13
131313$13 131313
13 13$
1313 13 0amp $
13 13
13$ 1313
13 $
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 46 Hybrid wall construction with 2 spray foam and fibrous fill
191 Thermal Control
131313131313
13 1313 13
$amp $ amp 13
131313$(
13 13 13 13
1313
Building Science Corporation amp$ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 47 Therm analysis of hybrid wall system
Table 12 Calculated R-value for a hybrid wall system
192 Moisture Control
+ amp 13
$1313
13 $1313 $ 13
13
13 +(
131313
131313)13(
193 Constructability and Cost
13131313131313
13
1313
194 Other Considerations
1313
1313 1313
1313
Building Science Corporation -+ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 13
13
110 Case 10 Double Stud Wall with Spray Foam
amp 13 13
) 13 13
)13
amp 13 13
131313
13
13 131313
1313 13 1313 13
13
Figure 48 Double stud wall with 2 of spray foam and cellulose fill
1101 Thermal Control
$) 13
13(amp() $
13$
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 49 Therm analysis of double stud wall construction with spray foam
Table 13 Calculated whole wall R-value for a double stud wall system with 2rdquo spray foam
1102 Moisture Control
13 13 (13
13 13
13 1313 13
13 13
($$13(amp$$$13
13 1313 1313 13 13
13 13 13 $13 13
1313 amp+ 13
1313 amp1313 13
13 1313 amp
1313 13 13
1103 Constructability and Cost
13131313 13 13
13131313131313
Building Science Corporation )( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1104 Other Considerations
13 13 13 1313
131313(13 131313 1313 13 amp
13 13 (
131313 1313 13 13 13 13
13 (
111 Case 11 Offset Frame Wall with Exterior Spray Foam
131313 1313 13 1313
13 13 13 13( 13 1313131313 131313
13 1313$ 13 13 13(
13 13 13 13 13 13
$ 13 ( 1313 13 131313131313
1313 13 13( 1313
13 13 13(
13 13 13 13 13(
1313 ( 1313 13 13
1313 (1313 13 13 13 1313
1313 13 13( 1313
13 13 13$13 -++13 13
131313 1313 1313(13 13
13 13 13 )13
13 13 13 13 13 13 13 13
(
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 50 Offset frame wall construction with exterior spray foam
1111 Thermal Control
131313 13 1313131313
1313 131313
13 13 13131313
13 13 13 13 13 13 13
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 51 Therm analysis of an offset truss wall with exterior spray foam
Table 14 Calculated whole wall R-value for an offset framed wall with exterior spray foam
1112 Moisture Control
13
$ 13$
+amp13
+amp$
13 131313
1313 ()amp$13
13 13131313
1313$
1313
13
(-amp$
1113 Constructability and Cost
13 $13
1313 13 13 $
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($( $$
$ $($$($$+
1114 Other Considerations
$$amp$(amp$+
( $ $(($$
ampamp$amp$+
amp$+13 $-
$$(($
112 Case 12 Exterior Insulation Finish System (EIFS)
$(- 13()+
$ $
amp$$+amp$
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13$$$$+
(amp $
$amp(amp$(+
$$ampamp 13$ampamp$(
$amp(+($$
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($amp$13$$
($$ 13($$+
Building Science Corporation 25 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 52 Wall construction using the EIFS cladding system
1121 Thermal Control
1313 1313
1313 1313
1313 131313
13 13 $
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 53 Thermal analysis of an EIFS wall system
Table 15 Calculated whole wall R-value for a EIFS wall system with 4rdquo of EPS
1122 Moisture Control
1313131313131313
131313amp1313
13131313
131313amp
13131313131313
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1123 Constructability and Cost
131313131313
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1124 Other Considerations
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30 Forest St Somerville MA 02143
D Conclusions
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Table 16 Summary of all calculated R-values
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30 Forest St Somerville MA 02143
Table 17 Hours of potential winter time air leakage condensation
13
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Table 18 Wall Comparison Chart
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30 Forest St Somerville MA 02143
Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
Figure 19 Inward vapor drive relative humidity of poly or GWB for Case 1 Case 2 and Case 9
13$13 131313
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13131313131313
Figure 20 Inward vapor drive relative humidity of poly or GWB for Case 3 Case 4 and Case 5
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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Figure 21 Inward vapor drive relative humidity of poly or GWB for Case 4 and Case 10
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30 Forest St Somerville MA 02143
Figure 22 Inward vapor drive relative humidity of poly or GWB for Case 8
() 13
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13
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 23 Inward vapor drive relative humidity of poly or GWB for Cases 5 8 and 11
224 Wall Drying
-
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Building Science Corporation 02 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 24 Drying Curves for Case 1 and Case 2
13131313 13 13
13 131313
Figure 25 Drying curves for Case 3 Case 4 and Case 5
13 1313
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13
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 26 Drying curves for Case 8
1313 1313$13)1313
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13(13131313 13)13 13 13
13131313131313131313131313 13
1313131313 13131313 131313
131313131313131313131313131313 13
Figure 27 Drying Curves for Case 4 and Case 10 with and without a poly vapor barrier
131313131313 1313 131313
131313 13131313 13 13
Building Science Corporation 30 Forest St Somerville MA 02143
(+ wwwbuildingsciencecom
13 1313
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Figure 28 Drying Curves for Case 5 and Case 11
23 Enclosure Durability
13 13 13
131313
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13 13 13 1313
13131313 13
1313
1313
24 Buildability
13 1313
13131313 13
1313 13 13131313
1313
13
1313 131313
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
25 Material Use
13131313 1313
13131313$131313
13 1313131313131313131313
13131313131313$1313131313
1313131313
131313$
26 Cost
13 131313131313
1313$1313131313
13131313 1313
13$13amp1313 213
1313 )+$1313 13)-$+
1313$13131313 1313131313
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C Results
1 CASE 1 STANDARD CONSTRUCTION PRACTICE
131313131313--0130(13
13131301313131313133 13$)-2
131313 13131313$
Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 29 Standard construction practice
111 Thermal Control
13) amp( 13
+amp-
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13 $ 13 13
13 13
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Building Science Corporation - wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 30 Therm modeling of Case 1 - 2x6 construction
1313 13 13 131313 (-$13
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13131313131313131313
13 13131313131313131313)+
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13
Table 5 Summary of R-value results from Therm modeling for Case 1
1313131313131313131313
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13 1313131313
1313 1313 131313
13 13 13 13
112 Moisture Control
1313131313 13131313 13
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30 Forest St Somerville MA 02143
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113 Constructability and Cost
13
amp13
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114 Other Considerations
13
13amp
131+13
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12 Case 2 Advanced framing with insulated sheathing
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30 Forest St Somerville MA 02143
Figure 31 Advanced framing construction
121 Thermal Control
131313 13$13 1313
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1313131313 1313
131313 1313
13131313131313
131313amp1313 13
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 32 Therm modeling of Case 2 advanced framing with 1 XPS insulated sheathing
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Table 6 Summary of R-value results from Therm modeling for Case 2
122 Moisture Control
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30 Forest St Somerville MA 02143
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123 Constructability and Cost
131313131313
13130$
13-$131313
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13 1313
124 Other Considerations
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131313$1313 13
1313
13 Case 3 Interior 2x3 horizontal strapping
13 $
13$
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 33 2x6 wall construction with interior strapping
131 Thermal Control
1313 1313131313
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1313131313 1313
131313 13 13131313
1313 1313131313
1313 1313 1313131313
13131313 13
13 13131313$
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 34 Therm analysis of horizontally strapped wall
13$13-amp0)132amp 13$
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Table 7 Calculated R-value of an interior horizontal strapped wall
132 Moisture Control
13
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13 $amp
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30 Forest St Somerville MA 02143
13 13
133 Constructability and Cost
1313$
13 13
1313
134 Other Considerations
13
131313
13
14 Case 4 Double Stud
1313
131313
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 35 Double stud wall
141 Thermal Control
13
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30 Forest St Somerville MA 02143
13$131313
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)-0 13 13
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Figure 36 Therm model of the double stud wall
Table 8 Calculated R-value of a double stud wall
142 Moisture Control
13131313
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131313
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30 Forest St Somerville MA 02143
13
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13 1313
13
13
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143 Constructability and Cost
13
amp 13
144 Other Considerations
13 13
131313
13 1313
15 Case 5 Truss Wall
1313
13 13131313
13 13 13
131313amp
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 37 Truss wall construction
151 Thermal Control
1313
13 13(
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131313
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13 13
13131313
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 38 Therm results of the truss wall
Table 9 Calculated R-value for truss wall
152 Moisture Control
13
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30 Forest St Somerville MA 02143
153 Constructability and Cost
13
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154 Other Considerations
13 $$
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16 Case 6 Structural Insulated Panel Systems (SIPs)
131313
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amp
Figure 39 SIPs wall construction
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
161 Thermal Control
13 13
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13 $ (
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Figure 40 Therm results of SIPs panel analysis
Table 10 Calculated R-value for a Sips wall system
162 Moisture Control
13 $ $ amp
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)
Building Science Corporation 33 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($$
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163 Constructability and Cost
$amp $$$$ $
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164 Other Considerations
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17 Case 7 Insulated Concrete Forms (ICFs)
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30 Forest St Somerville MA 02143
Figure 41 ICF wall construction
171 Thermal Control
1313
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Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 42 Nine inch foam ICF with five inches of EPS
Figure 43 Fifteen inch foam ICF with five inches of EPS
13 13 1313
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13131313$amp
172 Moisture Control
1313131313131313 13$amp131313
131313 13amp13
$ 13$1313$13ampamp
13 1313$1313131313
131313amp13
1313131313 13amp
173 Constructability and Cost
13131313 $1313$13$ 13
13 13$1313amp13$13
1313 amp13 13
13 13 1313$
13$13 13$131313
131313 1313 13$amp
174 Other Considerations
13 1313 131313$
13$$131313 1313 13
13amp131313$ 131313
1313 13amp13 131313
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30 Forest St Somerville MA 02143
13 1313 13131313 1313 13 13
13 13 1313 13
131313 13131313131313
131313 1313 13 13 1313 13
131313131313 131313
13131313
18 Case 8 Advanced framing with spray foam
13 13 13131313131313
13131313131313 13$
13 $
Figure 44 2x6 wall construction with spray foam insulation
181 Thermal Control
13131313 1313131313 13131313131313
131313131313
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30 Forest St Somerville MA 02143
13amp13 1313$
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13-
Figure 45 Therm modeling of spray foam wall and rim joist
13 amp amp+1+
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Table 11 Therm results of spray foam insulation analysis
182 Moisture Control
13 $
1313 13
131313
13
Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313 13 13
13 13 $ 13
131313 23
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13 13
1313
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1313 13
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1313 13 13
13 1313$
(+) 13 13 1313+-
113 13 13 13
-1313+-$
183 Constructability and Cost
13 13 13 13
$13 13
1313 13 13$
184 Other Considerations
1313
$ 1313
13 1313$
19 Case 9 Hybrid Wall Insulation ndash Flash and Fill
13 $1313
1313 $13
131313$13 131313
13 13$
1313 13 0amp $
13 13
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 46 Hybrid wall construction with 2 spray foam and fibrous fill
191 Thermal Control
131313131313
13 1313 13
$amp $ amp 13
131313$(
13 13 13 13
1313
Building Science Corporation amp$ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 47 Therm analysis of hybrid wall system
Table 12 Calculated R-value for a hybrid wall system
192 Moisture Control
+ amp 13
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193 Constructability and Cost
13131313131313
13
1313
194 Other Considerations
1313
1313 1313
1313
Building Science Corporation -+ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 13
13
110 Case 10 Double Stud Wall with Spray Foam
amp 13 13
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131313
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13
Figure 48 Double stud wall with 2 of spray foam and cellulose fill
1101 Thermal Control
$) 13
13(amp() $
13$
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 49 Therm analysis of double stud wall construction with spray foam
Table 13 Calculated whole wall R-value for a double stud wall system with 2rdquo spray foam
1102 Moisture Control
13 13 (13
13 13
13 1313 13
13 13
($$13(amp$$$13
13 1313 1313 13 13
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1313 amp1313 13
13 1313 amp
1313 13 13
1103 Constructability and Cost
13131313 13 13
13131313131313
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30 Forest St Somerville MA 02143
1104 Other Considerations
13 13 13 1313
131313(13 131313 1313 13 amp
13 13 (
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111 Case 11 Offset Frame Wall with Exterior Spray Foam
131313 1313 13 1313
13 13 13 13( 13 1313131313 131313
13 1313$ 13 13 13(
13 13 13 13 13 13
$ 13 ( 1313 13 131313131313
1313 13 13( 1313
13 13 13(
13 13 13 13 13(
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 50 Offset frame wall construction with exterior spray foam
1111 Thermal Control
131313 13 1313131313
1313 131313
13 13 13131313
13 13 13 13 13 13 13
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 51 Therm analysis of an offset truss wall with exterior spray foam
Table 14 Calculated whole wall R-value for an offset framed wall with exterior spray foam
1112 Moisture Control
13
$ 13$
+amp13
+amp$
13 131313
1313 ()amp$13
13 13131313
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1113 Constructability and Cost
13 $13
1313 13 13 $
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($( $$
$ $($$($$+
1114 Other Considerations
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112 Case 12 Exterior Insulation Finish System (EIFS)
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Building Science Corporation 25 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 52 Wall construction using the EIFS cladding system
1121 Thermal Control
1313 1313
1313 1313
1313 131313
13 13 $
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 53 Thermal analysis of an EIFS wall system
Table 15 Calculated whole wall R-value for a EIFS wall system with 4rdquo of EPS
1122 Moisture Control
1313131313131313
131313amp1313
13131313
131313amp
13131313131313
13 13 13+ 13amp 131313
1313131313 131313) amp
1123 Constructability and Cost
131313131313
131313amp1313131313amp
131313131313 1313 13
1313amp
1124 Other Considerations
131313131313amp 13
13131313 131313
13amp13$1313131313
1313131313amp 131313131313
131313131313amp
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
D Conclusions
amp 1313
)- 13$13
13131313 1313
1313
Table 16 Summary of all calculated R-values
131313 amp
amp(
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13 ampamp(1313$
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( 131313$1313$13
amp+( 1313
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1313131313 13
131313
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) 13
131313$
$13
13
Building Science Corporation -) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 17 Hours of potential winter time air leakage condensation
13
) 1313amp$13
amp 13amp 13)
amp13amp$13
131313
13
1313
13
1313
Building Science Corporation (amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 18 Wall Comparison Chart
$$ 13$$13
$13
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amp$13
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13 13 amp
$13$1313$ 13$
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$ $13$ amp13 $13
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13 $amp13
13$13 13
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30 Forest St Somerville MA 02143
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30 Forest St Somerville MA 02143
E Works Cited
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Building Science Corporation GF wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
1313amp$
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Figure 21 Inward vapor drive relative humidity of poly or GWB for Case 4 and Case 10
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 22 Inward vapor drive relative humidity of poly or GWB for Case 8
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Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 23 Inward vapor drive relative humidity of poly or GWB for Cases 5 8 and 11
224 Wall Drying
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Building Science Corporation 02 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 24 Drying Curves for Case 1 and Case 2
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Figure 25 Drying curves for Case 3 Case 4 and Case 5
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 26 Drying curves for Case 8
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Figure 27 Drying Curves for Case 4 and Case 10 with and without a poly vapor barrier
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Building Science Corporation 30 Forest St Somerville MA 02143
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Figure 28 Drying Curves for Case 5 and Case 11
23 Enclosure Durability
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24 Buildability
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30 Forest St Somerville MA 02143
25 Material Use
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26 Cost
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13131313 1313
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1 CASE 1 STANDARD CONSTRUCTION PRACTICE
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30 Forest St Somerville MA 02143
Figure 29 Standard construction practice
111 Thermal Control
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Building Science Corporation - wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 30 Therm modeling of Case 1 - 2x6 construction
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Table 5 Summary of R-value results from Therm modeling for Case 1
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112 Moisture Control
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30 Forest St Somerville MA 02143
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113 Constructability and Cost
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114 Other Considerations
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30 Forest St Somerville MA 02143
Figure 31 Advanced framing construction
121 Thermal Control
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30 Forest St Somerville MA 02143
Figure 32 Therm modeling of Case 2 advanced framing with 1 XPS insulated sheathing
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Table 6 Summary of R-value results from Therm modeling for Case 2
122 Moisture Control
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123 Constructability and Cost
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124 Other Considerations
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13 Case 3 Interior 2x3 horizontal strapping
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30 Forest St Somerville MA 02143
Figure 33 2x6 wall construction with interior strapping
131 Thermal Control
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30 Forest St Somerville MA 02143
Figure 34 Therm analysis of horizontally strapped wall
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Table 7 Calculated R-value of an interior horizontal strapped wall
132 Moisture Control
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133 Constructability and Cost
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134 Other Considerations
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Figure 35 Double stud wall
141 Thermal Control
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30 Forest St Somerville MA 02143
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Figure 36 Therm model of the double stud wall
Table 8 Calculated R-value of a double stud wall
142 Moisture Control
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30 Forest St Somerville MA 02143
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143 Constructability and Cost
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144 Other Considerations
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15 Case 5 Truss Wall
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Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 37 Truss wall construction
151 Thermal Control
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30 Forest St Somerville MA 02143
Figure 38 Therm results of the truss wall
Table 9 Calculated R-value for truss wall
152 Moisture Control
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30 Forest St Somerville MA 02143
153 Constructability and Cost
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154 Other Considerations
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16 Case 6 Structural Insulated Panel Systems (SIPs)
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Figure 39 SIPs wall construction
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30 Forest St Somerville MA 02143
161 Thermal Control
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Table 10 Calculated R-value for a Sips wall system
162 Moisture Control
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Building Science Corporation 33 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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163 Constructability and Cost
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17 Case 7 Insulated Concrete Forms (ICFs)
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30 Forest St Somerville MA 02143
Figure 41 ICF wall construction
171 Thermal Control
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30 Forest St Somerville MA 02143
Figure 42 Nine inch foam ICF with five inches of EPS
Figure 43 Fifteen inch foam ICF with five inches of EPS
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172 Moisture Control
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173 Constructability and Cost
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174 Other Considerations
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30 Forest St Somerville MA 02143
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18 Case 8 Advanced framing with spray foam
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Figure 44 2x6 wall construction with spray foam insulation
181 Thermal Control
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30 Forest St Somerville MA 02143
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Figure 45 Therm modeling of spray foam wall and rim joist
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Table 11 Therm results of spray foam insulation analysis
182 Moisture Control
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30 Forest St Somerville MA 02143
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183 Constructability and Cost
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184 Other Considerations
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19 Case 9 Hybrid Wall Insulation ndash Flash and Fill
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 46 Hybrid wall construction with 2 spray foam and fibrous fill
191 Thermal Control
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30 Forest St Somerville MA 02143
Figure 47 Therm analysis of hybrid wall system
Table 12 Calculated R-value for a hybrid wall system
192 Moisture Control
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193 Constructability and Cost
13131313131313
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194 Other Considerations
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30 Forest St Somerville MA 02143
13 13
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110 Case 10 Double Stud Wall with Spray Foam
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Figure 48 Double stud wall with 2 of spray foam and cellulose fill
1101 Thermal Control
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Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 49 Therm analysis of double stud wall construction with spray foam
Table 13 Calculated whole wall R-value for a double stud wall system with 2rdquo spray foam
1102 Moisture Control
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1103 Constructability and Cost
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30 Forest St Somerville MA 02143
1104 Other Considerations
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111 Case 11 Offset Frame Wall with Exterior Spray Foam
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30 Forest St Somerville MA 02143
Figure 50 Offset frame wall construction with exterior spray foam
1111 Thermal Control
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13 13 13 13 13 13 13
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 51 Therm analysis of an offset truss wall with exterior spray foam
Table 14 Calculated whole wall R-value for an offset framed wall with exterior spray foam
1112 Moisture Control
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30 Forest St Somerville MA 02143
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1114 Other Considerations
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112 Case 12 Exterior Insulation Finish System (EIFS)
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Building Science Corporation 25 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 52 Wall construction using the EIFS cladding system
1121 Thermal Control
1313 1313
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Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 53 Thermal analysis of an EIFS wall system
Table 15 Calculated whole wall R-value for a EIFS wall system with 4rdquo of EPS
1122 Moisture Control
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1123 Constructability and Cost
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1124 Other Considerations
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D Conclusions
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30 Forest St Somerville MA 02143
Table 17 Hours of potential winter time air leakage condensation
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30 Forest St Somerville MA 02143
Table 18 Wall Comparison Chart
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Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
Figure 22 Inward vapor drive relative humidity of poly or GWB for Case 8
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Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 23 Inward vapor drive relative humidity of poly or GWB for Cases 5 8 and 11
224 Wall Drying
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Building Science Corporation 02 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 24 Drying Curves for Case 1 and Case 2
13131313 13 13
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Figure 25 Drying curves for Case 3 Case 4 and Case 5
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 26 Drying curves for Case 8
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Figure 27 Drying Curves for Case 4 and Case 10 with and without a poly vapor barrier
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Building Science Corporation 30 Forest St Somerville MA 02143
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Figure 28 Drying Curves for Case 5 and Case 11
23 Enclosure Durability
13 13 13
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13 13 13 1313
13131313 13
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24 Buildability
13 1313
13131313 13
1313 13 13131313
1313
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1313 131313
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
25 Material Use
13131313 1313
13131313$131313
13 1313131313131313131313
13131313131313$1313131313
1313131313
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26 Cost
13 131313131313
1313$1313131313
13131313 1313
13$13amp1313 213
1313 )+$1313 13)-$+
1313$13131313 1313131313
131313$
C Results
1 CASE 1 STANDARD CONSTRUCTION PRACTICE
131313131313--0130(13
13131301313131313133 13$)-2
131313 13131313$
Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 29 Standard construction practice
111 Thermal Control
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Building Science Corporation - wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 30 Therm modeling of Case 1 - 2x6 construction
1313 13 13 131313 (-$13
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13
Table 5 Summary of R-value results from Therm modeling for Case 1
1313131313131313131313
131313 131313 13 13
13 1313131313
1313 1313 131313
13 13 13 13
112 Moisture Control
1313131313 13131313 13
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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113 Constructability and Cost
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114 Other Considerations
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12 Case 2 Advanced framing with insulated sheathing
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Building Science Corporation 0 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 31 Advanced framing construction
121 Thermal Control
131313 13$13 1313
1313 13$13$1313 13
$$)amp $$)13$$13 13) 13
1313131313 1313
131313(-(13$amp-( 1313amp
+(13$13$1313$1313amp13
1313131313 1313
131313 1313
13131313131313
131313amp1313 13
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 32 Therm modeling of Case 2 advanced framing with 1 XPS insulated sheathing
amp $ $ 13 + 2 3$$35
$) 3( -(3 1(2($
$ amp 2($ )
$ ($ $
)13 ( amp amp
3(2 213 (
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Table 6 Summary of R-value results from Therm modeling for Case 2
122 Moisture Control
$
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Building Science Corporation 00 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
131313$ 1313
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2 131313
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123 Constructability and Cost
131313131313
13130$
13-$131313
131313(13
$$13131313
13 1313
124 Other Considerations
amp 1313
1313
1313$ 13 13
131313$1313 13
1313
13 Case 3 Interior 2x3 horizontal strapping
13 $
13$
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 33 2x6 wall construction with interior strapping
131 Thermal Control
1313 1313131313
1313131313 amp
1313131313 1313
131313 13 13131313
1313 1313131313
1313 1313 1313131313
13131313 13
13 13131313$
131313 13
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 34 Therm analysis of horizontally strapped wall
13$13-amp0)132amp 13$
3-1 1amp13 13
amp 13 13amp
Table 7 Calculated R-value of an interior horizontal strapped wall
132 Moisture Control
13
(1313$amp
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$amp
13$ 13$
13 $amp
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Building Science Corporation 1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 13
133 Constructability and Cost
1313$
13 13
1313
134 Other Considerations
13
131313
13
14 Case 4 Double Stud
1313
131313
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 35 Double stud wall
141 Thermal Control
13
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1313
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30 Forest St Somerville MA 02143
13$131313
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Figure 36 Therm model of the double stud wall
Table 8 Calculated R-value of a double stud wall
142 Moisture Control
13131313
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131313
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30 Forest St Somerville MA 02143
13
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13 1313
13
13
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143 Constructability and Cost
13
amp 13
144 Other Considerations
13 13
131313
13 1313
15 Case 5 Truss Wall
1313
13 13131313
13 13 13
131313amp
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 37 Truss wall construction
151 Thermal Control
1313
13 13(
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amp
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1313
)-13
131313
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13 13
13131313
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 38 Therm results of the truss wall
Table 9 Calculated R-value for truss wall
152 Moisture Control
13
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30 Forest St Somerville MA 02143
153 Constructability and Cost
13
13131313
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154 Other Considerations
13 $$
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)
16 Case 6 Structural Insulated Panel Systems (SIPs)
131313
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amp
Figure 39 SIPs wall construction
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
161 Thermal Control
13 13
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Figure 40 Therm results of SIPs panel analysis
Table 10 Calculated R-value for a Sips wall system
162 Moisture Control
13 $ $ amp
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amp
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)
Building Science Corporation 33 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($$
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163 Constructability and Cost
$amp $$$$ $
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164 Other Considerations
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17 Case 7 Insulated Concrete Forms (ICFs)
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 41 ICF wall construction
171 Thermal Control
1313
1313 1313
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amp)$)
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 42 Nine inch foam ICF with five inches of EPS
Figure 43 Fifteen inch foam ICF with five inches of EPS
13 13 1313
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172 Moisture Control
1313131313131313 13$amp131313
131313 13amp13
$ 13$1313$13ampamp
13 1313$1313131313
131313amp13
1313131313 13amp
173 Constructability and Cost
13131313 $1313$13$ 13
13 13$1313amp13$13
1313 amp13 13
13 13 1313$
13$13 13$131313
131313 1313 13$amp
174 Other Considerations
13 1313 131313$
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13amp131313$ 131313
1313 13amp13 131313
Building Science Corporation () wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 1313 13131313 1313 13 13
13 13 1313 13
131313 13131313131313
131313 1313 13 13 1313 13
131313131313 131313
13131313
18 Case 8 Advanced framing with spray foam
13 13 13131313131313
13131313131313 13$
13 $
Figure 44 2x6 wall construction with spray foam insulation
181 Thermal Control
13131313 1313131313 13131313131313
131313131313
Building Science Corporation amp( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13amp13 1313$
13amp
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$131313
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13-
Figure 45 Therm modeling of spray foam wall and rim joist
13 amp amp+1+
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amp
Table 11 Therm results of spray foam insulation analysis
182 Moisture Control
13 $
1313 13
131313
13
Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313 13 13
13 13 $ 13
131313 23
(+-)$
13 13
1313
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1313 13
1313 3
1313$
1313 13 13
13 1313$
(+) 13 13 1313+-
113 13 13 13
-1313+-$
183 Constructability and Cost
13 13 13 13
$13 13
1313 13 13$
184 Other Considerations
1313
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19 Case 9 Hybrid Wall Insulation ndash Flash and Fill
13 $1313
1313 $13
131313$13 131313
13 13$
1313 13 0amp $
13 13
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13 $
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 46 Hybrid wall construction with 2 spray foam and fibrous fill
191 Thermal Control
131313131313
13 1313 13
$amp $ amp 13
131313$(
13 13 13 13
1313
Building Science Corporation amp$ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 47 Therm analysis of hybrid wall system
Table 12 Calculated R-value for a hybrid wall system
192 Moisture Control
+ amp 13
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193 Constructability and Cost
13131313131313
13
1313
194 Other Considerations
1313
1313 1313
1313
Building Science Corporation -+ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 13
13
110 Case 10 Double Stud Wall with Spray Foam
amp 13 13
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131313
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13
Figure 48 Double stud wall with 2 of spray foam and cellulose fill
1101 Thermal Control
$) 13
13(amp() $
13$
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 49 Therm analysis of double stud wall construction with spray foam
Table 13 Calculated whole wall R-value for a double stud wall system with 2rdquo spray foam
1102 Moisture Control
13 13 (13
13 13
13 1313 13
13 13
($$13(amp$$$13
13 1313 1313 13 13
13 13 13 $13 13
1313 amp+ 13
1313 amp1313 13
13 1313 amp
1313 13 13
1103 Constructability and Cost
13131313 13 13
13131313131313
Building Science Corporation )( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1104 Other Considerations
13 13 13 1313
131313(13 131313 1313 13 amp
13 13 (
131313 1313 13 13 13 13
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111 Case 11 Offset Frame Wall with Exterior Spray Foam
131313 1313 13 1313
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13 1313$ 13 13 13(
13 13 13 13 13 13
$ 13 ( 1313 13 131313131313
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 50 Offset frame wall construction with exterior spray foam
1111 Thermal Control
131313 13 1313131313
1313 131313
13 13 13131313
13 13 13 13 13 13 13
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 51 Therm analysis of an offset truss wall with exterior spray foam
Table 14 Calculated whole wall R-value for an offset framed wall with exterior spray foam
1112 Moisture Control
13
$ 13$
+amp13
+amp$
13 131313
1313 ()amp$13
13 13131313
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1113 Constructability and Cost
13 $13
1313 13 13 $
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30 Forest St Somerville MA 02143
$($( $$
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1114 Other Considerations
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112 Case 12 Exterior Insulation Finish System (EIFS)
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Building Science Corporation 25 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 52 Wall construction using the EIFS cladding system
1121 Thermal Control
1313 1313
1313 1313
1313 131313
13 13 $
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 53 Thermal analysis of an EIFS wall system
Table 15 Calculated whole wall R-value for a EIFS wall system with 4rdquo of EPS
1122 Moisture Control
1313131313131313
131313amp1313
13131313
131313amp
13131313131313
13 13 13+ 13amp 131313
1313131313 131313) amp
1123 Constructability and Cost
131313131313
131313amp1313131313amp
131313131313 1313 13
1313amp
1124 Other Considerations
131313131313amp 13
13131313 131313
13amp13$1313131313
1313131313amp 131313131313
131313131313amp
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
D Conclusions
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13131313 1313
1313
Table 16 Summary of all calculated R-values
131313 amp
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1313131313 13
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Building Science Corporation -) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 17 Hours of potential winter time air leakage condensation
13
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30 Forest St Somerville MA 02143
Table 18 Wall Comparison Chart
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$13$1313$ 13$
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30 Forest St Somerville MA 02143
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30 Forest St Somerville MA 02143
E Works Cited
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30 Forest St Somerville MA 02143
Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
Figure 23 Inward vapor drive relative humidity of poly or GWB for Cases 5 8 and 11
224 Wall Drying
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Building Science Corporation 02 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 24 Drying Curves for Case 1 and Case 2
13131313 13 13
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Figure 25 Drying curves for Case 3 Case 4 and Case 5
13 1313
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 26 Drying curves for Case 8
1313 1313$13)1313
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13(13131313 13)13 13 13
13131313131313131313131313 13
1313131313 13131313 131313
131313131313131313131313131313 13
Figure 27 Drying Curves for Case 4 and Case 10 with and without a poly vapor barrier
131313131313 1313 131313
131313 13131313 13 13
Building Science Corporation 30 Forest St Somerville MA 02143
(+ wwwbuildingsciencecom
13 1313
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Figure 28 Drying Curves for Case 5 and Case 11
23 Enclosure Durability
13 13 13
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13 13 13 1313
13131313 13
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24 Buildability
13 1313
13131313 13
1313 13 13131313
1313
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
25 Material Use
13131313 1313
13131313$131313
13 1313131313131313131313
13131313131313$1313131313
1313131313
131313$
26 Cost
13 131313131313
1313$1313131313
13131313 1313
13$13amp1313 213
1313 )+$1313 13)-$+
1313$13131313 1313131313
131313$
C Results
1 CASE 1 STANDARD CONSTRUCTION PRACTICE
131313131313--0130(13
13131301313131313133 13$)-2
131313 13131313$
Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 29 Standard construction practice
111 Thermal Control
13) amp( 13
+amp-
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13 $ 13 13
13 13
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Building Science Corporation - wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 30 Therm modeling of Case 1 - 2x6 construction
1313 13 13 131313 (-$13
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13131313131313131313
13 13131313131313131313)+
13)-13131313131313 13
13
Table 5 Summary of R-value results from Therm modeling for Case 1
1313131313131313131313
131313 131313 13 13
13 1313131313
1313 1313 131313
13 13 13 13
112 Moisture Control
1313131313 13131313 13
++ +13 1313)+ )- 131313
131313131313131313 13 1313131313(amp
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
131313
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113 Constructability and Cost
13
amp13
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114 Other Considerations
13
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131+13
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12 Case 2 Advanced framing with insulated sheathing
1313
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Building Science Corporation 0 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 31 Advanced framing construction
121 Thermal Control
131313 13$13 1313
1313 13$13$1313 13
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1313131313 1313
131313(-(13$amp-( 1313amp
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1313131313 1313
131313 1313
13131313131313
131313amp1313 13
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 32 Therm modeling of Case 2 advanced framing with 1 XPS insulated sheathing
amp $ $ 13 + 2 3$$35
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3(2 213 (
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Table 6 Summary of R-value results from Therm modeling for Case 2
122 Moisture Control
$
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Building Science Corporation 00 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
131313$ 1313
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2 131313
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123 Constructability and Cost
131313131313
13130$
13-$131313
131313(13
$$13131313
13 1313
124 Other Considerations
amp 1313
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131313$1313 13
1313
13 Case 3 Interior 2x3 horizontal strapping
13 $
13$
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 33 2x6 wall construction with interior strapping
131 Thermal Control
1313 1313131313
1313131313 amp
1313131313 1313
131313 13 13131313
1313 1313131313
1313 1313 1313131313
13131313 13
13 13131313$
131313 13
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 34 Therm analysis of horizontally strapped wall
13$13-amp0)132amp 13$
3-1 1amp13 13
amp 13 13amp
Table 7 Calculated R-value of an interior horizontal strapped wall
132 Moisture Control
13
(1313$amp
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$amp
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13 $amp
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Building Science Corporation 1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 13
133 Constructability and Cost
1313$
13 13
1313
134 Other Considerations
13
131313
13
14 Case 4 Double Stud
1313
131313
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 35 Double stud wall
141 Thermal Control
13
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1313
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13
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13 13
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13$131313
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Figure 36 Therm model of the double stud wall
Table 8 Calculated R-value of a double stud wall
142 Moisture Control
13131313
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Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13
13)amp 13
13 1313
13
13
13(13$)- 13)amp
143 Constructability and Cost
13
amp 13
144 Other Considerations
13 13
131313
13 1313
15 Case 5 Truss Wall
1313
13 13131313
13 13 13
131313amp
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 37 Truss wall construction
151 Thermal Control
1313
13 13(
1313)1313
13 $)13)+
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13
1313
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131313
13
13 $)
13 13
13131313
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 38 Therm results of the truss wall
Table 9 Calculated R-value for truss wall
152 Moisture Control
13
1313
13 1313
13amp(
131313
13 13
1313
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13
13
13 13$13
13
13
1313
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Building Science Corporation amp$ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
153 Constructability and Cost
13
13131313
13
13+($13
13
$ 13
154 Other Considerations
13 $$
1313amp
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16 Case 6 Structural Insulated Panel Systems (SIPs)
131313
13 13$13 13
amp
Figure 39 SIPs wall construction
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
161 Thermal Control
13 13
-)2)4+(4)4+(6)4+) 13
)13 $$
$2)6)
13 $ (
(( $
)
$1302( -
27( $ amp03)4 13
)$ amp02)5
-0( $)
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amp 13$)
Figure 40 Therm results of SIPs panel analysis
Table 10 Calculated R-value for a Sips wall system
162 Moisture Control
13 $ $ amp
$ ) ( 13
amp
-1311) 13 $
)
Building Science Corporation 33 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($$
amp$$+$($
163 Constructability and Cost
$amp $$$$ $
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+amp
164 Other Considerations
()($$$((
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)(ampamp13+$(amp
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)($
17 Case 7 Insulated Concrete Forms (ICFs)
(amp($
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 41 ICF wall construction
171 Thermal Control
1313
1313 1313
131313 (
+$)$13 13($
amp)$)
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 42 Nine inch foam ICF with five inches of EPS
Figure 43 Fifteen inch foam ICF with five inches of EPS
13 13 1313
13 1313131313$13$1313
1313amp1313 13 1313
13131313$amp
172 Moisture Control
1313131313131313 13$amp131313
131313 13amp13
$ 13$1313$13ampamp
13 1313$1313131313
131313amp13
1313131313 13amp
173 Constructability and Cost
13131313 $1313$13$ 13
13 13$1313amp13$13
1313 amp13 13
13 13 1313$
13$13 13$131313
131313 1313 13$amp
174 Other Considerations
13 1313 131313$
13$$131313 1313 13
13amp131313$ 131313
1313 13amp13 131313
Building Science Corporation () wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 1313 13131313 1313 13 13
13 13 1313 13
131313 13131313131313
131313 1313 13 13 1313 13
131313131313 131313
13131313
18 Case 8 Advanced framing with spray foam
13 13 13131313131313
13131313131313 13$
13 $
Figure 44 2x6 wall construction with spray foam insulation
181 Thermal Control
13131313 1313131313 13131313131313
131313131313
Building Science Corporation amp( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13amp13 1313$
13amp
0$+ $0
13$
$131313
13131313$1313
13-
Figure 45 Therm modeling of spray foam wall and rim joist
13 amp amp+1+
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13-amp(1+)13
amp 131
amp
Table 11 Therm results of spray foam insulation analysis
182 Moisture Control
13 $
1313 13
131313
13
Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313 13 13
13 13 $ 13
131313 23
(+-)$
13 13
1313
13 (+)$
1313 13
1313 3
1313$
1313 13 13
13 1313$
(+) 13 13 1313+-
113 13 13 13
-1313+-$
183 Constructability and Cost
13 13 13 13
$13 13
1313 13 13$
184 Other Considerations
1313
$ 1313
13 1313$
19 Case 9 Hybrid Wall Insulation ndash Flash and Fill
13 $1313
1313 $13
131313$13 131313
13 13$
1313 13 0amp $
13 13
13$ 1313
13 $
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 46 Hybrid wall construction with 2 spray foam and fibrous fill
191 Thermal Control
131313131313
13 1313 13
$amp $ amp 13
131313$(
13 13 13 13
1313
Building Science Corporation amp$ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 47 Therm analysis of hybrid wall system
Table 12 Calculated R-value for a hybrid wall system
192 Moisture Control
+ amp 13
$1313
13 $1313 $ 13
13
13 +(
131313
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193 Constructability and Cost
13131313131313
13
1313
194 Other Considerations
1313
1313 1313
1313
Building Science Corporation -+ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 13
13
110 Case 10 Double Stud Wall with Spray Foam
amp 13 13
) 13 13
)13
amp 13 13
131313
13
13 131313
1313 13 1313 13
13
Figure 48 Double stud wall with 2 of spray foam and cellulose fill
1101 Thermal Control
$) 13
13(amp() $
13$
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 49 Therm analysis of double stud wall construction with spray foam
Table 13 Calculated whole wall R-value for a double stud wall system with 2rdquo spray foam
1102 Moisture Control
13 13 (13
13 13
13 1313 13
13 13
($$13(amp$$$13
13 1313 1313 13 13
13 13 13 $13 13
1313 amp+ 13
1313 amp1313 13
13 1313 amp
1313 13 13
1103 Constructability and Cost
13131313 13 13
13131313131313
Building Science Corporation )( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1104 Other Considerations
13 13 13 1313
131313(13 131313 1313 13 amp
13 13 (
131313 1313 13 13 13 13
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111 Case 11 Offset Frame Wall with Exterior Spray Foam
131313 1313 13 1313
13 13 13 13( 13 1313131313 131313
13 1313$ 13 13 13(
13 13 13 13 13 13
$ 13 ( 1313 13 131313131313
1313 13 13( 1313
13 13 13(
13 13 13 13 13(
1313 ( 1313 13 13
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1313 13 13( 1313
13 13 13$13 -++13 13
131313 1313 1313(13 13
13 13 13 )13
13 13 13 13 13 13 13 13
(
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 50 Offset frame wall construction with exterior spray foam
1111 Thermal Control
131313 13 1313131313
1313 131313
13 13 13131313
13 13 13 13 13 13 13
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 51 Therm analysis of an offset truss wall with exterior spray foam
Table 14 Calculated whole wall R-value for an offset framed wall with exterior spray foam
1112 Moisture Control
13
$ 13$
+amp13
+amp$
13 131313
1313 ()amp$13
13 13131313
1313$
1313
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1113 Constructability and Cost
13 $13
1313 13 13 $
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($( $$
$ $($$($$+
1114 Other Considerations
$$amp$(amp$+
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ampamp$amp$+
amp$+13 $-
$$(($
112 Case 12 Exterior Insulation Finish System (EIFS)
$(- 13()+
$ $
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-016532443405amp(+
13$$$$+
(amp $
$amp(amp$(+
$$ampamp 13$ampamp$(
$amp(+($$
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($amp$13$$
($$ 13($$+
Building Science Corporation 25 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 52 Wall construction using the EIFS cladding system
1121 Thermal Control
1313 1313
1313 1313
1313 131313
13 13 $
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 53 Thermal analysis of an EIFS wall system
Table 15 Calculated whole wall R-value for a EIFS wall system with 4rdquo of EPS
1122 Moisture Control
1313131313131313
131313amp1313
13131313
131313amp
13131313131313
13 13 13+ 13amp 131313
1313131313 131313) amp
1123 Constructability and Cost
131313131313
131313amp1313131313amp
131313131313 1313 13
1313amp
1124 Other Considerations
131313131313amp 13
13131313 131313
13amp13$1313131313
1313131313amp 131313131313
131313131313amp
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
D Conclusions
amp 1313
)- 13$13
13131313 1313
1313
Table 16 Summary of all calculated R-values
131313 amp
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amp+( 1313
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1313131313 13
131313
13 $
) 13
131313$
$13
13
Building Science Corporation -) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 17 Hours of potential winter time air leakage condensation
13
) 1313amp$13
amp 13amp 13)
amp13amp$13
131313
13
1313
13
1313
Building Science Corporation (amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 18 Wall Comparison Chart
$$ 13$$13
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13 13 amp
$13$1313$ 13$
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$ $13$ amp13 $13
13
13 $amp13
13$13 13
$ $ 13amp
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30 Forest St Somerville MA 02143
1313
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13 1313
13
131313 1313
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30 Forest St Somerville MA 02143
E Works Cited
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Building Science Corporation GF wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
Figure 24 Drying Curves for Case 1 and Case 2
13131313 13 13
13 131313
Figure 25 Drying curves for Case 3 Case 4 and Case 5
13 1313
13131313131313
131313 13
13
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 26 Drying curves for Case 8
1313 1313$13)1313
1313$ 13amp 13)1313 13amp13 13 1313
13(13131313 13)13 13 13
13131313131313131313131313 13
1313131313 13131313 131313
131313131313131313131313131313 13
Figure 27 Drying Curves for Case 4 and Case 10 with and without a poly vapor barrier
131313131313 1313 131313
131313 13131313 13 13
Building Science Corporation 30 Forest St Somerville MA 02143
(+ wwwbuildingsciencecom
13 1313
1313 131313
$$ 1313
amp 13 131313
13
1313 13
13
131313 1313
13
Figure 28 Drying Curves for Case 5 and Case 11
23 Enclosure Durability
13 13 13
131313
13 131313
13 13 13 1313
13131313 13
1313
1313
24 Buildability
13 1313
13131313 13
1313 13 13131313
1313
13
1313 131313
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
25 Material Use
13131313 1313
13131313$131313
13 1313131313131313131313
13131313131313$1313131313
1313131313
131313$
26 Cost
13 131313131313
1313$1313131313
13131313 1313
13$13amp1313 213
1313 )+$1313 13)-$+
1313$13131313 1313131313
131313$
C Results
1 CASE 1 STANDARD CONSTRUCTION PRACTICE
131313131313--0130(13
13131301313131313133 13$)-2
131313 13131313$
Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 29 Standard construction practice
111 Thermal Control
13) amp( 13
+amp-
13 13 ( ampampampamp(amp13$
13 $ 13 13
13 13
13(
Building Science Corporation - wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 30 Therm modeling of Case 1 - 2x6 construction
1313 13 13 131313 (-$13
13 131313 1313 13
131313) )13131313131313(-131313
13131313131313131313
13 13131313131313131313)+
13)-13131313131313 13
13
Table 5 Summary of R-value results from Therm modeling for Case 1
1313131313131313131313
131313 131313 13 13
13 1313131313
1313 1313 131313
13 13 13 13
112 Moisture Control
1313131313 13131313 13
++ +13 1313)+ )- 131313
131313131313131313 13 1313131313(amp
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
131313
amp 13
2-)0--)04011+amp
113 Constructability and Cost
13
amp13
13amp
114 Other Considerations
13
13amp
131+13
amp 13
13amp
12 Case 2 Advanced framing with insulated sheathing
1313
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amp 3131(ampamp
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13 13
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13
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Building Science Corporation 0 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 31 Advanced framing construction
121 Thermal Control
131313 13$13 1313
1313 13$13$1313 13
$$)amp $$)13$$13 13) 13
1313131313 1313
131313(-(13$amp-( 1313amp
+(13$13$1313$1313amp13
1313131313 1313
131313 1313
13131313131313
131313amp1313 13
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 32 Therm modeling of Case 2 advanced framing with 1 XPS insulated sheathing
amp $ $ 13 + 2 3$$35
$) 3( -(3 1(2($
$ amp 2($ )
$ ($ $
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3(2 213 (
(
) $ $3(
Table 6 Summary of R-value results from Therm modeling for Case 2
122 Moisture Control
$
$$$
( )
$ (-(2( $
3$ 76(23$amp (
$
amp (4 $ $13
(13
$amp$ amp (
Building Science Corporation 00 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
131313$ 1313
1++-++13
13
13 1313 13
13)-
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131313 $ )
2 131313
13
123 Constructability and Cost
131313131313
13130$
13-$131313
131313(13
$$13131313
13 1313
124 Other Considerations
amp 1313
1313
1313$ 13 13
131313$1313 13
1313
13 Case 3 Interior 2x3 horizontal strapping
13 $
13$
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 33 2x6 wall construction with interior strapping
131 Thermal Control
1313 1313131313
1313131313 amp
1313131313 1313
131313 13 13131313
1313 1313131313
1313 1313 1313131313
13131313 13
13 13131313$
131313 13
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 34 Therm analysis of horizontally strapped wall
13$13-amp0)132amp 13$
3-1 1amp13 13
amp 13 13amp
Table 7 Calculated R-value of an interior horizontal strapped wall
132 Moisture Control
13
(1313$amp
$ 13)
-amp $$13 13$
$amp
13$ 13$
13 $amp
$
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$ $ 13
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Building Science Corporation 1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 13
133 Constructability and Cost
1313$
13 13
1313
134 Other Considerations
13
131313
13
14 Case 4 Double Stud
1313
131313
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 35 Double stud wall
141 Thermal Control
13
1313) 13
)13
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13 13
1313
1313
13
13
131313
) 13
13 13
$ 13
1313
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13$131313
-amp1313
1313 13$ 13131313
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)-0 13 13
amp13 1313$
13amp$1amp(13 13
-amp $
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13$$
1313amp
Figure 36 Therm model of the double stud wall
Table 8 Calculated R-value of a double stud wall
142 Moisture Control
13131313
01313 13
amp13 $$13
1313 1313amp
131313$13
131313
13amp 0++ 13$-
1313$
13 13)-amp
Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13
13)amp 13
13 1313
13
13
13(13$)- 13)amp
143 Constructability and Cost
13
amp 13
144 Other Considerations
13 13
131313
13 1313
15 Case 5 Truss Wall
1313
13 13131313
13 13 13
131313amp
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 37 Truss wall construction
151 Thermal Control
1313
13 13(
1313)1313
13 $)13)+
amp
13
1313
)-13
131313
13
13 $)
13 13
13131313
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 38 Therm results of the truss wall
Table 9 Calculated R-value for truss wall
152 Moisture Control
13
1313
13 1313
13amp(
131313
13 13
1313
13$
13
13
13 13$13
13
13
1313
13
Building Science Corporation amp$ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
153 Constructability and Cost
13
13131313
13
13+($13
13
$ 13
154 Other Considerations
13 $$
1313amp
)
16 Case 6 Structural Insulated Panel Systems (SIPs)
131313
13 13$13 13
amp
Figure 39 SIPs wall construction
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
161 Thermal Control
13 13
-)2)4+(4)4+(6)4+) 13
)13 $$
$2)6)
13 $ (
(( $
)
$1302( -
27( $ amp03)4 13
)$ amp02)5
-0( $)
amp $ (
$( ) $
amp 13$)
Figure 40 Therm results of SIPs panel analysis
Table 10 Calculated R-value for a Sips wall system
162 Moisture Control
13 $ $ amp
$ ) ( 13
amp
-1311) 13 $
)
Building Science Corporation 33 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($$
amp$$+$($
163 Constructability and Cost
$amp $$$$ $
()$$(($(
+amp
164 Other Considerations
()($$$((
$) $ $$
$)$amp$amp($
$)
$$)($amp
amp)ampamp13+$$$
)(ampamp13+$(amp
$
- +13amp()$)$
)($
17 Case 7 Insulated Concrete Forms (ICFs)
(amp($
$$$
$$$
amp)($$
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 41 ICF wall construction
171 Thermal Control
1313
1313 1313
131313 (
+$)$13 13($
amp)$)
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 42 Nine inch foam ICF with five inches of EPS
Figure 43 Fifteen inch foam ICF with five inches of EPS
13 13 1313
13 1313131313$13$1313
1313amp1313 13 1313
13131313$amp
172 Moisture Control
1313131313131313 13$amp131313
131313 13amp13
$ 13$1313$13ampamp
13 1313$1313131313
131313amp13
1313131313 13amp
173 Constructability and Cost
13131313 $1313$13$ 13
13 13$1313amp13$13
1313 amp13 13
13 13 1313$
13$13 13$131313
131313 1313 13$amp
174 Other Considerations
13 1313 131313$
13$$131313 1313 13
13amp131313$ 131313
1313 13amp13 131313
Building Science Corporation () wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 1313 13131313 1313 13 13
13 13 1313 13
131313 13131313131313
131313 1313 13 13 1313 13
131313131313 131313
13131313
18 Case 8 Advanced framing with spray foam
13 13 13131313131313
13131313131313 13$
13 $
Figure 44 2x6 wall construction with spray foam insulation
181 Thermal Control
13131313 1313131313 13131313131313
131313131313
Building Science Corporation amp( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13amp13 1313$
13amp
0$+ $0
13$
$131313
13131313$1313
13-
Figure 45 Therm modeling of spray foam wall and rim joist
13 amp amp+1+
$+ amp
13-amp(1+)13
amp 131
amp
Table 11 Therm results of spray foam insulation analysis
182 Moisture Control
13 $
1313 13
131313
13
Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313 13 13
13 13 $ 13
131313 23
(+-)$
13 13
1313
13 (+)$
1313 13
1313 3
1313$
1313 13 13
13 1313$
(+) 13 13 1313+-
113 13 13 13
-1313+-$
183 Constructability and Cost
13 13 13 13
$13 13
1313 13 13$
184 Other Considerations
1313
$ 1313
13 1313$
19 Case 9 Hybrid Wall Insulation ndash Flash and Fill
13 $1313
1313 $13
131313$13 131313
13 13$
1313 13 0amp $
13 13
13$ 1313
13 $
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 46 Hybrid wall construction with 2 spray foam and fibrous fill
191 Thermal Control
131313131313
13 1313 13
$amp $ amp 13
131313$(
13 13 13 13
1313
Building Science Corporation amp$ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 47 Therm analysis of hybrid wall system
Table 12 Calculated R-value for a hybrid wall system
192 Moisture Control
+ amp 13
$1313
13 $1313 $ 13
13
13 +(
131313
131313)13(
193 Constructability and Cost
13131313131313
13
1313
194 Other Considerations
1313
1313 1313
1313
Building Science Corporation -+ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 13
13
110 Case 10 Double Stud Wall with Spray Foam
amp 13 13
) 13 13
)13
amp 13 13
131313
13
13 131313
1313 13 1313 13
13
Figure 48 Double stud wall with 2 of spray foam and cellulose fill
1101 Thermal Control
$) 13
13(amp() $
13$
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 49 Therm analysis of double stud wall construction with spray foam
Table 13 Calculated whole wall R-value for a double stud wall system with 2rdquo spray foam
1102 Moisture Control
13 13 (13
13 13
13 1313 13
13 13
($$13(amp$$$13
13 1313 1313 13 13
13 13 13 $13 13
1313 amp+ 13
1313 amp1313 13
13 1313 amp
1313 13 13
1103 Constructability and Cost
13131313 13 13
13131313131313
Building Science Corporation )( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1104 Other Considerations
13 13 13 1313
131313(13 131313 1313 13 amp
13 13 (
131313 1313 13 13 13 13
13 (
111 Case 11 Offset Frame Wall with Exterior Spray Foam
131313 1313 13 1313
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13 1313$ 13 13 13(
13 13 13 13 13 13
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13 13 13 13 13 13 13 13
(
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30 Forest St Somerville MA 02143
Figure 50 Offset frame wall construction with exterior spray foam
1111 Thermal Control
131313 13 1313131313
1313 131313
13 13 13131313
13 13 13 13 13 13 13
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 51 Therm analysis of an offset truss wall with exterior spray foam
Table 14 Calculated whole wall R-value for an offset framed wall with exterior spray foam
1112 Moisture Control
13
$ 13$
+amp13
+amp$
13 131313
1313 ()amp$13
13 13131313
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1313
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1113 Constructability and Cost
13 $13
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30 Forest St Somerville MA 02143
$($( $$
$ $($$($$+
1114 Other Considerations
$$amp$(amp$+
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ampamp$amp$+
amp$+13 $-
$$(($
112 Case 12 Exterior Insulation Finish System (EIFS)
$(- 13()+
$ $
amp$$+amp$
-016532443405amp(+
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(amp $
$amp(amp$(+
$$ampamp 13$ampamp$(
$amp(+($$
amp$$$ $()+
($amp$13$$
($$ 13($$+
Building Science Corporation 25 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 52 Wall construction using the EIFS cladding system
1121 Thermal Control
1313 1313
1313 1313
1313 131313
13 13 $
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 53 Thermal analysis of an EIFS wall system
Table 15 Calculated whole wall R-value for a EIFS wall system with 4rdquo of EPS
1122 Moisture Control
1313131313131313
131313amp1313
13131313
131313amp
13131313131313
13 13 13+ 13amp 131313
1313131313 131313) amp
1123 Constructability and Cost
131313131313
131313amp1313131313amp
131313131313 1313 13
1313amp
1124 Other Considerations
131313131313amp 13
13131313 131313
13amp13$1313131313
1313131313amp 131313131313
131313131313amp
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
D Conclusions
amp 1313
)- 13$13
13131313 1313
1313
Table 16 Summary of all calculated R-values
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) 13
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$13
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30 Forest St Somerville MA 02143
Table 17 Hours of potential winter time air leakage condensation
13
) 1313amp$13
amp 13amp 13)
amp13amp$13
131313
13
1313
13
1313
Building Science Corporation (amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 18 Wall Comparison Chart
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13 13 amp
$13$1313$ 13$
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13 $amp13
13$13 13
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30 Forest St Somerville MA 02143
Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
Figure 26 Drying curves for Case 8
1313 1313$13)1313
1313$ 13amp 13)1313 13amp13 13 1313
13(13131313 13)13 13 13
13131313131313131313131313 13
1313131313 13131313 131313
131313131313131313131313131313 13
Figure 27 Drying Curves for Case 4 and Case 10 with and without a poly vapor barrier
131313131313 1313 131313
131313 13131313 13 13
Building Science Corporation 30 Forest St Somerville MA 02143
(+ wwwbuildingsciencecom
13 1313
1313 131313
$$ 1313
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1313 13
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Figure 28 Drying Curves for Case 5 and Case 11
23 Enclosure Durability
13 13 13
131313
13 131313
13 13 13 1313
13131313 13
1313
1313
24 Buildability
13 1313
13131313 13
1313 13 13131313
1313
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1313 131313
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
25 Material Use
13131313 1313
13131313$131313
13 1313131313131313131313
13131313131313$1313131313
1313131313
131313$
26 Cost
13 131313131313
1313$1313131313
13131313 1313
13$13amp1313 213
1313 )+$1313 13)-$+
1313$13131313 1313131313
131313$
C Results
1 CASE 1 STANDARD CONSTRUCTION PRACTICE
131313131313--0130(13
13131301313131313133 13$)-2
131313 13131313$
Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 29 Standard construction practice
111 Thermal Control
13) amp( 13
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13 $ 13 13
13 13
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Building Science Corporation - wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 30 Therm modeling of Case 1 - 2x6 construction
1313 13 13 131313 (-$13
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131313) )13131313131313(-131313
13131313131313131313
13 13131313131313131313)+
13)-13131313131313 13
13
Table 5 Summary of R-value results from Therm modeling for Case 1
1313131313131313131313
131313 131313 13 13
13 1313131313
1313 1313 131313
13 13 13 13
112 Moisture Control
1313131313 13131313 13
++ +13 1313)+ )- 131313
131313131313131313 13 1313131313(amp
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
131313
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2-)0--)04011+amp
113 Constructability and Cost
13
amp13
13amp
114 Other Considerations
13
13amp
131+13
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13amp
12 Case 2 Advanced framing with insulated sheathing
1313
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Building Science Corporation 0 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 31 Advanced framing construction
121 Thermal Control
131313 13$13 1313
1313 13$13$1313 13
$$)amp $$)13$$13 13) 13
1313131313 1313
131313(-(13$amp-( 1313amp
+(13$13$1313$1313amp13
1313131313 1313
131313 1313
13131313131313
131313amp1313 13
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 32 Therm modeling of Case 2 advanced framing with 1 XPS insulated sheathing
amp $ $ 13 + 2 3$$35
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Table 6 Summary of R-value results from Therm modeling for Case 2
122 Moisture Control
$
$$$
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$ (-(2( $
3$ 76(23$amp (
$
amp (4 $ $13
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Building Science Corporation 00 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
131313$ 1313
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13)-
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2 131313
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123 Constructability and Cost
131313131313
13130$
13-$131313
131313(13
$$13131313
13 1313
124 Other Considerations
amp 1313
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131313$1313 13
1313
13 Case 3 Interior 2x3 horizontal strapping
13 $
13$
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 33 2x6 wall construction with interior strapping
131 Thermal Control
1313 1313131313
1313131313 amp
1313131313 1313
131313 13 13131313
1313 1313131313
1313 1313 1313131313
13131313 13
13 13131313$
131313 13
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 34 Therm analysis of horizontally strapped wall
13$13-amp0)132amp 13$
3-1 1amp13 13
amp 13 13amp
Table 7 Calculated R-value of an interior horizontal strapped wall
132 Moisture Control
13
(1313$amp
$ 13)
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13 $amp
$
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Building Science Corporation 1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 13
133 Constructability and Cost
1313$
13 13
1313
134 Other Considerations
13
131313
13
14 Case 4 Double Stud
1313
131313
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 35 Double stud wall
141 Thermal Control
13
1313) 13
)13
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13 13
1313
1313
13
13
131313
) 13
13 13
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13$131313
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)-0 13 13
amp13 1313$
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Figure 36 Therm model of the double stud wall
Table 8 Calculated R-value of a double stud wall
142 Moisture Control
13131313
01313 13
amp13 $$13
1313 1313amp
131313$13
131313
13amp 0++ 13$-
1313$
13 13)-amp
Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13
13)amp 13
13 1313
13
13
13(13$)- 13)amp
143 Constructability and Cost
13
amp 13
144 Other Considerations
13 13
131313
13 1313
15 Case 5 Truss Wall
1313
13 13131313
13 13 13
131313amp
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 37 Truss wall construction
151 Thermal Control
1313
13 13(
1313)1313
13 $)13)+
amp
13
1313
)-13
131313
13
13 $)
13 13
13131313
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 38 Therm results of the truss wall
Table 9 Calculated R-value for truss wall
152 Moisture Control
13
1313
13 1313
13amp(
131313
13 13
1313
13$
13
13
13 13$13
13
13
1313
13
Building Science Corporation amp$ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
153 Constructability and Cost
13
13131313
13
13+($13
13
$ 13
154 Other Considerations
13 $$
1313amp
)
16 Case 6 Structural Insulated Panel Systems (SIPs)
131313
13 13$13 13
amp
Figure 39 SIPs wall construction
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
161 Thermal Control
13 13
-)2)4+(4)4+(6)4+) 13
)13 $$
$2)6)
13 $ (
(( $
)
$1302( -
27( $ amp03)4 13
)$ amp02)5
-0( $)
amp $ (
$( ) $
amp 13$)
Figure 40 Therm results of SIPs panel analysis
Table 10 Calculated R-value for a Sips wall system
162 Moisture Control
13 $ $ amp
$ ) ( 13
amp
-1311) 13 $
)
Building Science Corporation 33 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($$
amp$$+$($
163 Constructability and Cost
$amp $$$$ $
()$$(($(
+amp
164 Other Considerations
()($$$((
$) $ $$
$)$amp$amp($
$)
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amp)ampamp13+$$$
)(ampamp13+$(amp
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- +13amp()$)$
)($
17 Case 7 Insulated Concrete Forms (ICFs)
(amp($
$$$
$$$
amp)($$
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 41 ICF wall construction
171 Thermal Control
1313
1313 1313
131313 (
+$)$13 13($
amp)$)
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 42 Nine inch foam ICF with five inches of EPS
Figure 43 Fifteen inch foam ICF with five inches of EPS
13 13 1313
13 1313131313$13$1313
1313amp1313 13 1313
13131313$amp
172 Moisture Control
1313131313131313 13$amp131313
131313 13amp13
$ 13$1313$13ampamp
13 1313$1313131313
131313amp13
1313131313 13amp
173 Constructability and Cost
13131313 $1313$13$ 13
13 13$1313amp13$13
1313 amp13 13
13 13 1313$
13$13 13$131313
131313 1313 13$amp
174 Other Considerations
13 1313 131313$
13$$131313 1313 13
13amp131313$ 131313
1313 13amp13 131313
Building Science Corporation () wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 1313 13131313 1313 13 13
13 13 1313 13
131313 13131313131313
131313 1313 13 13 1313 13
131313131313 131313
13131313
18 Case 8 Advanced framing with spray foam
13 13 13131313131313
13131313131313 13$
13 $
Figure 44 2x6 wall construction with spray foam insulation
181 Thermal Control
13131313 1313131313 13131313131313
131313131313
Building Science Corporation amp( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13amp13 1313$
13amp
0$+ $0
13$
$131313
13131313$1313
13-
Figure 45 Therm modeling of spray foam wall and rim joist
13 amp amp+1+
$+ amp
13-amp(1+)13
amp 131
amp
Table 11 Therm results of spray foam insulation analysis
182 Moisture Control
13 $
1313 13
131313
13
Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313 13 13
13 13 $ 13
131313 23
(+-)$
13 13
1313
13 (+)$
1313 13
1313 3
1313$
1313 13 13
13 1313$
(+) 13 13 1313+-
113 13 13 13
-1313+-$
183 Constructability and Cost
13 13 13 13
$13 13
1313 13 13$
184 Other Considerations
1313
$ 1313
13 1313$
19 Case 9 Hybrid Wall Insulation ndash Flash and Fill
13 $1313
1313 $13
131313$13 131313
13 13$
1313 13 0amp $
13 13
13$ 1313
13 $
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 46 Hybrid wall construction with 2 spray foam and fibrous fill
191 Thermal Control
131313131313
13 1313 13
$amp $ amp 13
131313$(
13 13 13 13
1313
Building Science Corporation amp$ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 47 Therm analysis of hybrid wall system
Table 12 Calculated R-value for a hybrid wall system
192 Moisture Control
+ amp 13
$1313
13 $1313 $ 13
13
13 +(
131313
131313)13(
193 Constructability and Cost
13131313131313
13
1313
194 Other Considerations
1313
1313 1313
1313
Building Science Corporation -+ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 13
13
110 Case 10 Double Stud Wall with Spray Foam
amp 13 13
) 13 13
)13
amp 13 13
131313
13
13 131313
1313 13 1313 13
13
Figure 48 Double stud wall with 2 of spray foam and cellulose fill
1101 Thermal Control
$) 13
13(amp() $
13$
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 49 Therm analysis of double stud wall construction with spray foam
Table 13 Calculated whole wall R-value for a double stud wall system with 2rdquo spray foam
1102 Moisture Control
13 13 (13
13 13
13 1313 13
13 13
($$13(amp$$$13
13 1313 1313 13 13
13 13 13 $13 13
1313 amp+ 13
1313 amp1313 13
13 1313 amp
1313 13 13
1103 Constructability and Cost
13131313 13 13
13131313131313
Building Science Corporation )( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1104 Other Considerations
13 13 13 1313
131313(13 131313 1313 13 amp
13 13 (
131313 1313 13 13 13 13
13 (
111 Case 11 Offset Frame Wall with Exterior Spray Foam
131313 1313 13 1313
13 13 13 13( 13 1313131313 131313
13 1313$ 13 13 13(
13 13 13 13 13 13
$ 13 ( 1313 13 131313131313
1313 13 13( 1313
13 13 13(
13 13 13 13 13(
1313 ( 1313 13 13
1313 (1313 13 13 13 1313
1313 13 13( 1313
13 13 13$13 -++13 13
131313 1313 1313(13 13
13 13 13 )13
13 13 13 13 13 13 13 13
(
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 50 Offset frame wall construction with exterior spray foam
1111 Thermal Control
131313 13 1313131313
1313 131313
13 13 13131313
13 13 13 13 13 13 13
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 51 Therm analysis of an offset truss wall with exterior spray foam
Table 14 Calculated whole wall R-value for an offset framed wall with exterior spray foam
1112 Moisture Control
13
$ 13$
+amp13
+amp$
13 131313
1313 ()amp$13
13 13131313
1313$
1313
13
(-amp$
1113 Constructability and Cost
13 $13
1313 13 13 $
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($( $$
$ $($$($$+
1114 Other Considerations
$$amp$(amp$+
( $ $(($$
ampamp$amp$+
amp$+13 $-
$$(($
112 Case 12 Exterior Insulation Finish System (EIFS)
$(- 13()+
$ $
amp$$+amp$
-016532443405amp(+
13$$$$+
(amp $
$amp(amp$(+
$$ampamp 13$ampamp$(
$amp(+($$
amp$$$ $()+
($amp$13$$
($$ 13($$+
Building Science Corporation 25 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 52 Wall construction using the EIFS cladding system
1121 Thermal Control
1313 1313
1313 1313
1313 131313
13 13 $
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 53 Thermal analysis of an EIFS wall system
Table 15 Calculated whole wall R-value for a EIFS wall system with 4rdquo of EPS
1122 Moisture Control
1313131313131313
131313amp1313
13131313
131313amp
13131313131313
13 13 13+ 13amp 131313
1313131313 131313) amp
1123 Constructability and Cost
131313131313
131313amp1313131313amp
131313131313 1313 13
1313amp
1124 Other Considerations
131313131313amp 13
13131313 131313
13amp13$1313131313
1313131313amp 131313131313
131313131313amp
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
D Conclusions
amp 1313
)- 13$13
13131313 1313
1313
Table 16 Summary of all calculated R-values
131313 amp
amp(
13amp 1313
13 ampamp(1313$
13amp) amp
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( 131313$1313$13
amp+( 1313
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amp 13131313
1313131313 13
131313
13 $
) 13
131313$
$13
13
Building Science Corporation -) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 17 Hours of potential winter time air leakage condensation
13
) 1313amp$13
amp 13amp 13)
amp13amp$13
131313
13
1313
13
1313
Building Science Corporation (amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 18 Wall Comparison Chart
$$ 13$$13
$13
amp$
amp$13
1313
(
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$( $ (
13
$ 13 amp amp
13 13 amp
$13$1313$ 13$
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$ $13$ amp13 $13
13
13 $amp13
13$13 13
$ $ 13amp
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Building Science Corporation +) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313
13
13 1313
13
131313 1313
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
E Works Cited
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+amp17 amp7- 7 $$( $+7amp1213 -amp9 $$amp$
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- ampamp amp07amp8amp$+ -amp$amp7CAAI9
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Building Science Corporation GF wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
13 1313
1313 131313
$$ 1313
amp 13 131313
13
1313 13
13
131313 1313
13
Figure 28 Drying Curves for Case 5 and Case 11
23 Enclosure Durability
13 13 13
131313
13 131313
13 13 13 1313
13131313 13
1313
1313
24 Buildability
13 1313
13131313 13
1313 13 13131313
1313
13
1313 131313
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
25 Material Use
13131313 1313
13131313$131313
13 1313131313131313131313
13131313131313$1313131313
1313131313
131313$
26 Cost
13 131313131313
1313$1313131313
13131313 1313
13$13amp1313 213
1313 )+$1313 13)-$+
1313$13131313 1313131313
131313$
C Results
1 CASE 1 STANDARD CONSTRUCTION PRACTICE
131313131313--0130(13
13131301313131313133 13$)-2
131313 13131313$
Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 29 Standard construction practice
111 Thermal Control
13) amp( 13
+amp-
13 13 ( ampampampamp(amp13$
13 $ 13 13
13 13
13(
Building Science Corporation - wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 30 Therm modeling of Case 1 - 2x6 construction
1313 13 13 131313 (-$13
13 131313 1313 13
131313) )13131313131313(-131313
13131313131313131313
13 13131313131313131313)+
13)-13131313131313 13
13
Table 5 Summary of R-value results from Therm modeling for Case 1
1313131313131313131313
131313 131313 13 13
13 1313131313
1313 1313 131313
13 13 13 13
112 Moisture Control
1313131313 13131313 13
++ +13 1313)+ )- 131313
131313131313131313 13 1313131313(amp
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
131313
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113 Constructability and Cost
13
amp13
13amp
114 Other Considerations
13
13amp
131+13
amp 13
13amp
12 Case 2 Advanced framing with insulated sheathing
1313
amp 13131313
amp 3131(ampamp
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13 13
amp
13amp $
13amp
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13
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Building Science Corporation 0 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 31 Advanced framing construction
121 Thermal Control
131313 13$13 1313
1313 13$13$1313 13
$$)amp $$)13$$13 13) 13
1313131313 1313
131313(-(13$amp-( 1313amp
+(13$13$1313$1313amp13
1313131313 1313
131313 1313
13131313131313
131313amp1313 13
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 32 Therm modeling of Case 2 advanced framing with 1 XPS insulated sheathing
amp $ $ 13 + 2 3$$35
$) 3( -(3 1(2($
$ amp 2($ )
$ ($ $
)13 ( amp amp
3(2 213 (
(
) $ $3(
Table 6 Summary of R-value results from Therm modeling for Case 2
122 Moisture Control
$
$$$
( )
$ (-(2( $
3$ 76(23$amp (
$
amp (4 $ $13
(13
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Building Science Corporation 00 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
131313$ 1313
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13 1313 13
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2 131313
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123 Constructability and Cost
131313131313
13130$
13-$131313
131313(13
$$13131313
13 1313
124 Other Considerations
amp 1313
1313
1313$ 13 13
131313$1313 13
1313
13 Case 3 Interior 2x3 horizontal strapping
13 $
13$
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 33 2x6 wall construction with interior strapping
131 Thermal Control
1313 1313131313
1313131313 amp
1313131313 1313
131313 13 13131313
1313 1313131313
1313 1313 1313131313
13131313 13
13 13131313$
131313 13
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 34 Therm analysis of horizontally strapped wall
13$13-amp0)132amp 13$
3-1 1amp13 13
amp 13 13amp
Table 7 Calculated R-value of an interior horizontal strapped wall
132 Moisture Control
13
(1313$amp
$ 13)
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13 $amp
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Building Science Corporation 1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 13
133 Constructability and Cost
1313$
13 13
1313
134 Other Considerations
13
131313
13
14 Case 4 Double Stud
1313
131313
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 35 Double stud wall
141 Thermal Control
13
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13$131313
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)-0 13 13
amp13 1313$
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-amp $
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1313amp
Figure 36 Therm model of the double stud wall
Table 8 Calculated R-value of a double stud wall
142 Moisture Control
13131313
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131313
13amp 0++ 13$-
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Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13
13)amp 13
13 1313
13
13
13(13$)- 13)amp
143 Constructability and Cost
13
amp 13
144 Other Considerations
13 13
131313
13 1313
15 Case 5 Truss Wall
1313
13 13131313
13 13 13
131313amp
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 37 Truss wall construction
151 Thermal Control
1313
13 13(
1313)1313
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amp
13
1313
)-13
131313
13
13 $)
13 13
13131313
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 38 Therm results of the truss wall
Table 9 Calculated R-value for truss wall
152 Moisture Control
13
1313
13 1313
13amp(
131313
13 13
1313
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13
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Building Science Corporation amp$ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
153 Constructability and Cost
13
13131313
13
13+($13
13
$ 13
154 Other Considerations
13 $$
1313amp
)
16 Case 6 Structural Insulated Panel Systems (SIPs)
131313
13 13$13 13
amp
Figure 39 SIPs wall construction
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
161 Thermal Control
13 13
-)2)4+(4)4+(6)4+) 13
)13 $$
$2)6)
13 $ (
(( $
)
$1302( -
27( $ amp03)4 13
)$ amp02)5
-0( $)
amp $ (
$( ) $
amp 13$)
Figure 40 Therm results of SIPs panel analysis
Table 10 Calculated R-value for a Sips wall system
162 Moisture Control
13 $ $ amp
$ ) ( 13
amp
-1311) 13 $
)
Building Science Corporation 33 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($$
amp$$+$($
163 Constructability and Cost
$amp $$$$ $
()$$(($(
+amp
164 Other Considerations
()($$$((
$) $ $$
$)$amp$amp($
$)
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amp)ampamp13+$$$
)(ampamp13+$(amp
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- +13amp()$)$
)($
17 Case 7 Insulated Concrete Forms (ICFs)
(amp($
$$$
$$$
amp)($$
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 41 ICF wall construction
171 Thermal Control
1313
1313 1313
131313 (
+$)$13 13($
amp)$)
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 42 Nine inch foam ICF with five inches of EPS
Figure 43 Fifteen inch foam ICF with five inches of EPS
13 13 1313
13 1313131313$13$1313
1313amp1313 13 1313
13131313$amp
172 Moisture Control
1313131313131313 13$amp131313
131313 13amp13
$ 13$1313$13ampamp
13 1313$1313131313
131313amp13
1313131313 13amp
173 Constructability and Cost
13131313 $1313$13$ 13
13 13$1313amp13$13
1313 amp13 13
13 13 1313$
13$13 13$131313
131313 1313 13$amp
174 Other Considerations
13 1313 131313$
13$$131313 1313 13
13amp131313$ 131313
1313 13amp13 131313
Building Science Corporation () wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 1313 13131313 1313 13 13
13 13 1313 13
131313 13131313131313
131313 1313 13 13 1313 13
131313131313 131313
13131313
18 Case 8 Advanced framing with spray foam
13 13 13131313131313
13131313131313 13$
13 $
Figure 44 2x6 wall construction with spray foam insulation
181 Thermal Control
13131313 1313131313 13131313131313
131313131313
Building Science Corporation amp( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13amp13 1313$
13amp
0$+ $0
13$
$131313
13131313$1313
13-
Figure 45 Therm modeling of spray foam wall and rim joist
13 amp amp+1+
$+ amp
13-amp(1+)13
amp 131
amp
Table 11 Therm results of spray foam insulation analysis
182 Moisture Control
13 $
1313 13
131313
13
Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313 13 13
13 13 $ 13
131313 23
(+-)$
13 13
1313
13 (+)$
1313 13
1313 3
1313$
1313 13 13
13 1313$
(+) 13 13 1313+-
113 13 13 13
-1313+-$
183 Constructability and Cost
13 13 13 13
$13 13
1313 13 13$
184 Other Considerations
1313
$ 1313
13 1313$
19 Case 9 Hybrid Wall Insulation ndash Flash and Fill
13 $1313
1313 $13
131313$13 131313
13 13$
1313 13 0amp $
13 13
13$ 1313
13 $
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 46 Hybrid wall construction with 2 spray foam and fibrous fill
191 Thermal Control
131313131313
13 1313 13
$amp $ amp 13
131313$(
13 13 13 13
1313
Building Science Corporation amp$ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 47 Therm analysis of hybrid wall system
Table 12 Calculated R-value for a hybrid wall system
192 Moisture Control
+ amp 13
$1313
13 $1313 $ 13
13
13 +(
131313
131313)13(
193 Constructability and Cost
13131313131313
13
1313
194 Other Considerations
1313
1313 1313
1313
Building Science Corporation -+ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 13
13
110 Case 10 Double Stud Wall with Spray Foam
amp 13 13
) 13 13
)13
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131313
13
13 131313
1313 13 1313 13
13
Figure 48 Double stud wall with 2 of spray foam and cellulose fill
1101 Thermal Control
$) 13
13(amp() $
13$
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 49 Therm analysis of double stud wall construction with spray foam
Table 13 Calculated whole wall R-value for a double stud wall system with 2rdquo spray foam
1102 Moisture Control
13 13 (13
13 13
13 1313 13
13 13
($$13(amp$$$13
13 1313 1313 13 13
13 13 13 $13 13
1313 amp+ 13
1313 amp1313 13
13 1313 amp
1313 13 13
1103 Constructability and Cost
13131313 13 13
13131313131313
Building Science Corporation )( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1104 Other Considerations
13 13 13 1313
131313(13 131313 1313 13 amp
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131313 1313 13 13 13 13
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111 Case 11 Offset Frame Wall with Exterior Spray Foam
131313 1313 13 1313
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13 1313$ 13 13 13(
13 13 13 13 13 13
$ 13 ( 1313 13 131313131313
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13 13 13 13 13(
1313 ( 1313 13 13
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13 13 13$13 -++13 13
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13 13 13 )13
13 13 13 13 13 13 13 13
(
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 50 Offset frame wall construction with exterior spray foam
1111 Thermal Control
131313 13 1313131313
1313 131313
13 13 13131313
13 13 13 13 13 13 13
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 51 Therm analysis of an offset truss wall with exterior spray foam
Table 14 Calculated whole wall R-value for an offset framed wall with exterior spray foam
1112 Moisture Control
13
$ 13$
+amp13
+amp$
13 131313
1313 ()amp$13
13 13131313
1313$
1313
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1113 Constructability and Cost
13 $13
1313 13 13 $
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($( $$
$ $($$($$+
1114 Other Considerations
$$amp$(amp$+
( $ $(($$
ampamp$amp$+
amp$+13 $-
$$(($
112 Case 12 Exterior Insulation Finish System (EIFS)
$(- 13()+
$ $
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-016532443405amp(+
13$$$$+
(amp $
$amp(amp$(+
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$amp(+($$
amp$$$ $()+
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($$ 13($$+
Building Science Corporation 25 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 52 Wall construction using the EIFS cladding system
1121 Thermal Control
1313 1313
1313 1313
1313 131313
13 13 $
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 53 Thermal analysis of an EIFS wall system
Table 15 Calculated whole wall R-value for a EIFS wall system with 4rdquo of EPS
1122 Moisture Control
1313131313131313
131313amp1313
13131313
131313amp
13131313131313
13 13 13+ 13amp 131313
1313131313 131313) amp
1123 Constructability and Cost
131313131313
131313amp1313131313amp
131313131313 1313 13
1313amp
1124 Other Considerations
131313131313amp 13
13131313 131313
13amp13$1313131313
1313131313amp 131313131313
131313131313amp
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
D Conclusions
amp 1313
)- 13$13
13131313 1313
1313
Table 16 Summary of all calculated R-values
131313 amp
amp(
13amp 1313
13 ampamp(1313$
13amp) amp
amp13$ 13$
131313 amp )
( 131313$1313$13
amp+( 1313
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amp 13131313
1313131313 13
131313
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) 13
131313$
$13
13
Building Science Corporation -) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 17 Hours of potential winter time air leakage condensation
13
) 1313amp$13
amp 13amp 13)
amp13amp$13
131313
13
1313
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1313
Building Science Corporation (amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 18 Wall Comparison Chart
$$ 13$$13
$13
amp$
amp$13
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13 13 amp
$13$1313$ 13$
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$ $13$ amp13 $13
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13 $amp13
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$ $ 13amp
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30 Forest St Somerville MA 02143
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30 Forest St Somerville MA 02143
E Works Cited
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=++13 G7CAAJgt9
279amp+- -ampamp2-$ -+ $amp + -amp$amp+
$2amp9 (((ampampampamp7-( 1+CJ=CAAHgt8DBBDBC9
-++-7139979139amp713997137amp13913913ampampamp913267113$amp5113)
- ampamp amp07amp8amp$+ -amp$amp7CAAI9
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+ amp07amp8amp$+ -amp$amp7CAAG9
(+amp7$$7ampampampamp$9 1+$(+amp13+-$amp+9amp
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Building Science Corporation GF wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
25 Material Use
13131313 1313
13131313$131313
13 1313131313131313131313
13131313131313$1313131313
1313131313
131313$
26 Cost
13 131313131313
1313$1313131313
13131313 1313
13$13amp1313 213
1313 )+$1313 13)-$+
1313$13131313 1313131313
131313$
C Results
1 CASE 1 STANDARD CONSTRUCTION PRACTICE
131313131313--0130(13
13131301313131313133 13$)-2
131313 13131313$
Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 29 Standard construction practice
111 Thermal Control
13) amp( 13
+amp-
13 13 ( ampampampamp(amp13$
13 $ 13 13
13 13
13(
Building Science Corporation - wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 30 Therm modeling of Case 1 - 2x6 construction
1313 13 13 131313 (-$13
13 131313 1313 13
131313) )13131313131313(-131313
13131313131313131313
13 13131313131313131313)+
13)-13131313131313 13
13
Table 5 Summary of R-value results from Therm modeling for Case 1
1313131313131313131313
131313 131313 13 13
13 1313131313
1313 1313 131313
13 13 13 13
112 Moisture Control
1313131313 13131313 13
++ +13 1313)+ )- 131313
131313131313131313 13 1313131313(amp
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
131313
amp 13
2-)0--)04011+amp
113 Constructability and Cost
13
amp13
13amp
114 Other Considerations
13
13amp
131+13
amp 13
13amp
12 Case 2 Advanced framing with insulated sheathing
1313
amp 13131313
amp 3131(ampamp
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13 13
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13amp
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13
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Building Science Corporation 0 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 31 Advanced framing construction
121 Thermal Control
131313 13$13 1313
1313 13$13$1313 13
$$)amp $$)13$$13 13) 13
1313131313 1313
131313(-(13$amp-( 1313amp
+(13$13$1313$1313amp13
1313131313 1313
131313 1313
13131313131313
131313amp1313 13
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 32 Therm modeling of Case 2 advanced framing with 1 XPS insulated sheathing
amp $ $ 13 + 2 3$$35
$) 3( -(3 1(2($
$ amp 2($ )
$ ($ $
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3(2 213 (
(
) $ $3(
Table 6 Summary of R-value results from Therm modeling for Case 2
122 Moisture Control
$
$$$
( )
$ (-(2( $
3$ 76(23$amp (
$
amp (4 $ $13
(13
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Building Science Corporation 00 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
131313$ 1313
1++-++13
13
13 1313 13
13)-
13
131313 $ )
2 131313
13
123 Constructability and Cost
131313131313
13130$
13-$131313
131313(13
$$13131313
13 1313
124 Other Considerations
amp 1313
1313
1313$ 13 13
131313$1313 13
1313
13 Case 3 Interior 2x3 horizontal strapping
13 $
13$
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 33 2x6 wall construction with interior strapping
131 Thermal Control
1313 1313131313
1313131313 amp
1313131313 1313
131313 13 13131313
1313 1313131313
1313 1313 1313131313
13131313 13
13 13131313$
131313 13
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 34 Therm analysis of horizontally strapped wall
13$13-amp0)132amp 13$
3-1 1amp13 13
amp 13 13amp
Table 7 Calculated R-value of an interior horizontal strapped wall
132 Moisture Control
13
(1313$amp
$ 13)
-amp $$13 13$
$amp
13$ 13$
13 $amp
$
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$ $ 13
amp
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Building Science Corporation 1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 13
133 Constructability and Cost
1313$
13 13
1313
134 Other Considerations
13
131313
13
14 Case 4 Double Stud
1313
131313
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 35 Double stud wall
141 Thermal Control
13
1313) 13
)13
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13 13
1313
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13
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13 13
$ 13
1313
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13$131313
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)-0 13 13
amp13 1313$
13amp$1amp(13 13
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Figure 36 Therm model of the double stud wall
Table 8 Calculated R-value of a double stud wall
142 Moisture Control
13131313
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131313$13
131313
13amp 0++ 13$-
1313$
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Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13
13)amp 13
13 1313
13
13
13(13$)- 13)amp
143 Constructability and Cost
13
amp 13
144 Other Considerations
13 13
131313
13 1313
15 Case 5 Truss Wall
1313
13 13131313
13 13 13
131313amp
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 37 Truss wall construction
151 Thermal Control
1313
13 13(
1313)1313
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amp
13
1313
)-13
131313
13
13 $)
13 13
13131313
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 38 Therm results of the truss wall
Table 9 Calculated R-value for truss wall
152 Moisture Control
13
1313
13 1313
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13
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30 Forest St Somerville MA 02143
153 Constructability and Cost
13
13131313
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13+($13
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154 Other Considerations
13 $$
1313amp
)
16 Case 6 Structural Insulated Panel Systems (SIPs)
131313
13 13$13 13
amp
Figure 39 SIPs wall construction
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
161 Thermal Control
13 13
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)13 $$
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13 $ (
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)
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27( $ amp03)4 13
)$ amp02)5
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amp 13$)
Figure 40 Therm results of SIPs panel analysis
Table 10 Calculated R-value for a Sips wall system
162 Moisture Control
13 $ $ amp
$ ) ( 13
amp
-1311) 13 $
)
Building Science Corporation 33 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($$
amp$$+$($
163 Constructability and Cost
$amp $$$$ $
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+amp
164 Other Considerations
()($$$((
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)(ampamp13+$(amp
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17 Case 7 Insulated Concrete Forms (ICFs)
(amp($
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 41 ICF wall construction
171 Thermal Control
1313
1313 1313
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+$)$13 13($
amp)$)
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 42 Nine inch foam ICF with five inches of EPS
Figure 43 Fifteen inch foam ICF with five inches of EPS
13 13 1313
13 1313131313$13$1313
1313amp1313 13 1313
13131313$amp
172 Moisture Control
1313131313131313 13$amp131313
131313 13amp13
$ 13$1313$13ampamp
13 1313$1313131313
131313amp13
1313131313 13amp
173 Constructability and Cost
13131313 $1313$13$ 13
13 13$1313amp13$13
1313 amp13 13
13 13 1313$
13$13 13$131313
131313 1313 13$amp
174 Other Considerations
13 1313 131313$
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13amp131313$ 131313
1313 13amp13 131313
Building Science Corporation () wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 1313 13131313 1313 13 13
13 13 1313 13
131313 13131313131313
131313 1313 13 13 1313 13
131313131313 131313
13131313
18 Case 8 Advanced framing with spray foam
13 13 13131313131313
13131313131313 13$
13 $
Figure 44 2x6 wall construction with spray foam insulation
181 Thermal Control
13131313 1313131313 13131313131313
131313131313
Building Science Corporation amp( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13amp13 1313$
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$131313
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13-
Figure 45 Therm modeling of spray foam wall and rim joist
13 amp amp+1+
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Table 11 Therm results of spray foam insulation analysis
182 Moisture Control
13 $
1313 13
131313
13
Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313 13 13
13 13 $ 13
131313 23
(+-)$
13 13
1313
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1313 13
1313 3
1313$
1313 13 13
13 1313$
(+) 13 13 1313+-
113 13 13 13
-1313+-$
183 Constructability and Cost
13 13 13 13
$13 13
1313 13 13$
184 Other Considerations
1313
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13 1313$
19 Case 9 Hybrid Wall Insulation ndash Flash and Fill
13 $1313
1313 $13
131313$13 131313
13 13$
1313 13 0amp $
13 13
13$ 1313
13 $
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 46 Hybrid wall construction with 2 spray foam and fibrous fill
191 Thermal Control
131313131313
13 1313 13
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131313$(
13 13 13 13
1313
Building Science Corporation amp$ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 47 Therm analysis of hybrid wall system
Table 12 Calculated R-value for a hybrid wall system
192 Moisture Control
+ amp 13
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193 Constructability and Cost
13131313131313
13
1313
194 Other Considerations
1313
1313 1313
1313
Building Science Corporation -+ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 13
13
110 Case 10 Double Stud Wall with Spray Foam
amp 13 13
) 13 13
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131313
13
13 131313
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13
Figure 48 Double stud wall with 2 of spray foam and cellulose fill
1101 Thermal Control
$) 13
13(amp() $
13$
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 49 Therm analysis of double stud wall construction with spray foam
Table 13 Calculated whole wall R-value for a double stud wall system with 2rdquo spray foam
1102 Moisture Control
13 13 (13
13 13
13 1313 13
13 13
($$13(amp$$$13
13 1313 1313 13 13
13 13 13 $13 13
1313 amp+ 13
1313 amp1313 13
13 1313 amp
1313 13 13
1103 Constructability and Cost
13131313 13 13
13131313131313
Building Science Corporation )( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1104 Other Considerations
13 13 13 1313
131313(13 131313 1313 13 amp
13 13 (
131313 1313 13 13 13 13
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111 Case 11 Offset Frame Wall with Exterior Spray Foam
131313 1313 13 1313
13 13 13 13( 13 1313131313 131313
13 1313$ 13 13 13(
13 13 13 13 13 13
$ 13 ( 1313 13 131313131313
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13 13 13 13 13(
1313 ( 1313 13 13
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1313 13 13( 1313
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131313 1313 1313(13 13
13 13 13 )13
13 13 13 13 13 13 13 13
(
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 50 Offset frame wall construction with exterior spray foam
1111 Thermal Control
131313 13 1313131313
1313 131313
13 13 13131313
13 13 13 13 13 13 13
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 51 Therm analysis of an offset truss wall with exterior spray foam
Table 14 Calculated whole wall R-value for an offset framed wall with exterior spray foam
1112 Moisture Control
13
$ 13$
+amp13
+amp$
13 131313
1313 ()amp$13
13 13131313
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1313
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1113 Constructability and Cost
13 $13
1313 13 13 $
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($( $$
$ $($$($$+
1114 Other Considerations
$$amp$(amp$+
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112 Case 12 Exterior Insulation Finish System (EIFS)
$(- 13()+
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Building Science Corporation 25 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 52 Wall construction using the EIFS cladding system
1121 Thermal Control
1313 1313
1313 1313
1313 131313
13 13 $
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 53 Thermal analysis of an EIFS wall system
Table 15 Calculated whole wall R-value for a EIFS wall system with 4rdquo of EPS
1122 Moisture Control
1313131313131313
131313amp1313
13131313
131313amp
13131313131313
13 13 13+ 13amp 131313
1313131313 131313) amp
1123 Constructability and Cost
131313131313
131313amp1313131313amp
131313131313 1313 13
1313amp
1124 Other Considerations
131313131313amp 13
13131313 131313
13amp13$1313131313
1313131313amp 131313131313
131313131313amp
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
D Conclusions
amp 1313
)- 13$13
13131313 1313
1313
Table 16 Summary of all calculated R-values
131313 amp
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1313131313 13
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) 13
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Building Science Corporation -) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 17 Hours of potential winter time air leakage condensation
13
) 1313amp$13
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amp13amp$13
131313
13
1313
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1313
Building Science Corporation (amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 18 Wall Comparison Chart
$$ 13$$13
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13 13 amp
$13$1313$ 13$
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13$13 13
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30 Forest St Somerville MA 02143
1313
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30 Forest St Somerville MA 02143
E Works Cited
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Building Science Corporation GF wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
Figure 29 Standard construction practice
111 Thermal Control
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Building Science Corporation - wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 30 Therm modeling of Case 1 - 2x6 construction
1313 13 13 131313 (-$13
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13131313131313131313
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13
Table 5 Summary of R-value results from Therm modeling for Case 1
1313131313131313131313
131313 131313 13 13
13 1313131313
1313 1313 131313
13 13 13 13
112 Moisture Control
1313131313 13131313 13
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
131313
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113 Constructability and Cost
13
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114 Other Considerations
13
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131+13
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12 Case 2 Advanced framing with insulated sheathing
1313
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Building Science Corporation 0 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 31 Advanced framing construction
121 Thermal Control
131313 13$13 1313
1313 13$13$1313 13
$$)amp $$)13$$13 13) 13
1313131313 1313
131313(-(13$amp-( 1313amp
+(13$13$1313$1313amp13
1313131313 1313
131313 1313
13131313131313
131313amp1313 13
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 32 Therm modeling of Case 2 advanced framing with 1 XPS insulated sheathing
amp $ $ 13 + 2 3$$35
$) 3( -(3 1(2($
$ amp 2($ )
$ ($ $
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3(2 213 (
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Table 6 Summary of R-value results from Therm modeling for Case 2
122 Moisture Control
$
$$$
( )
$ (-(2( $
3$ 76(23$amp (
$
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(13
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Building Science Corporation 00 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
131313$ 1313
1++-++13
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13 1313 13
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2 131313
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123 Constructability and Cost
131313131313
13130$
13-$131313
131313(13
$$13131313
13 1313
124 Other Considerations
amp 1313
1313
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131313$1313 13
1313
13 Case 3 Interior 2x3 horizontal strapping
13 $
13$
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 33 2x6 wall construction with interior strapping
131 Thermal Control
1313 1313131313
1313131313 amp
1313131313 1313
131313 13 13131313
1313 1313131313
1313 1313 1313131313
13131313 13
13 13131313$
131313 13
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 34 Therm analysis of horizontally strapped wall
13$13-amp0)132amp 13$
3-1 1amp13 13
amp 13 13amp
Table 7 Calculated R-value of an interior horizontal strapped wall
132 Moisture Control
13
(1313$amp
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$amp
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13 $amp
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Building Science Corporation 1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 13
133 Constructability and Cost
1313$
13 13
1313
134 Other Considerations
13
131313
13
14 Case 4 Double Stud
1313
131313
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 35 Double stud wall
141 Thermal Control
13
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1313
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13
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13 13
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13$131313
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Figure 36 Therm model of the double stud wall
Table 8 Calculated R-value of a double stud wall
142 Moisture Control
13131313
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amp13 $$13
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131313$13
131313
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Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13
13)amp 13
13 1313
13
13
13(13$)- 13)amp
143 Constructability and Cost
13
amp 13
144 Other Considerations
13 13
131313
13 1313
15 Case 5 Truss Wall
1313
13 13131313
13 13 13
131313amp
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 37 Truss wall construction
151 Thermal Control
1313
13 13(
1313)1313
13 $)13)+
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13
1313
)-13
131313
13
13 $)
13 13
13131313
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 38 Therm results of the truss wall
Table 9 Calculated R-value for truss wall
152 Moisture Control
13
1313
13 1313
13amp(
131313
13 13
1313
13$
13
13
13 13$13
13
13
1313
13
Building Science Corporation amp$ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
153 Constructability and Cost
13
13131313
13
13+($13
13
$ 13
154 Other Considerations
13 $$
1313amp
)
16 Case 6 Structural Insulated Panel Systems (SIPs)
131313
13 13$13 13
amp
Figure 39 SIPs wall construction
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
161 Thermal Control
13 13
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)13 $$
$2)6)
13 $ (
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$1302( -
27( $ amp03)4 13
)$ amp02)5
-0( $)
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amp 13$)
Figure 40 Therm results of SIPs panel analysis
Table 10 Calculated R-value for a Sips wall system
162 Moisture Control
13 $ $ amp
$ ) ( 13
amp
-1311) 13 $
)
Building Science Corporation 33 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($$
amp$$+$($
163 Constructability and Cost
$amp $$$$ $
()$$(($(
+amp
164 Other Considerations
()($$$((
$) $ $$
$)$amp$amp($
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)(ampamp13+$(amp
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- +13amp()$)$
)($
17 Case 7 Insulated Concrete Forms (ICFs)
(amp($
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 41 ICF wall construction
171 Thermal Control
1313
1313 1313
131313 (
+$)$13 13($
amp)$)
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 42 Nine inch foam ICF with five inches of EPS
Figure 43 Fifteen inch foam ICF with five inches of EPS
13 13 1313
13 1313131313$13$1313
1313amp1313 13 1313
13131313$amp
172 Moisture Control
1313131313131313 13$amp131313
131313 13amp13
$ 13$1313$13ampamp
13 1313$1313131313
131313amp13
1313131313 13amp
173 Constructability and Cost
13131313 $1313$13$ 13
13 13$1313amp13$13
1313 amp13 13
13 13 1313$
13$13 13$131313
131313 1313 13$amp
174 Other Considerations
13 1313 131313$
13$$131313 1313 13
13amp131313$ 131313
1313 13amp13 131313
Building Science Corporation () wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 1313 13131313 1313 13 13
13 13 1313 13
131313 13131313131313
131313 1313 13 13 1313 13
131313131313 131313
13131313
18 Case 8 Advanced framing with spray foam
13 13 13131313131313
13131313131313 13$
13 $
Figure 44 2x6 wall construction with spray foam insulation
181 Thermal Control
13131313 1313131313 13131313131313
131313131313
Building Science Corporation amp( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13amp13 1313$
13amp
0$+ $0
13$
$131313
13131313$1313
13-
Figure 45 Therm modeling of spray foam wall and rim joist
13 amp amp+1+
$+ amp
13-amp(1+)13
amp 131
amp
Table 11 Therm results of spray foam insulation analysis
182 Moisture Control
13 $
1313 13
131313
13
Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313 13 13
13 13 $ 13
131313 23
(+-)$
13 13
1313
13 (+)$
1313 13
1313 3
1313$
1313 13 13
13 1313$
(+) 13 13 1313+-
113 13 13 13
-1313+-$
183 Constructability and Cost
13 13 13 13
$13 13
1313 13 13$
184 Other Considerations
1313
$ 1313
13 1313$
19 Case 9 Hybrid Wall Insulation ndash Flash and Fill
13 $1313
1313 $13
131313$13 131313
13 13$
1313 13 0amp $
13 13
13$ 1313
13 $
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 46 Hybrid wall construction with 2 spray foam and fibrous fill
191 Thermal Control
131313131313
13 1313 13
$amp $ amp 13
131313$(
13 13 13 13
1313
Building Science Corporation amp$ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 47 Therm analysis of hybrid wall system
Table 12 Calculated R-value for a hybrid wall system
192 Moisture Control
+ amp 13
$1313
13 $1313 $ 13
13
13 +(
131313
131313)13(
193 Constructability and Cost
13131313131313
13
1313
194 Other Considerations
1313
1313 1313
1313
Building Science Corporation -+ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 13
13
110 Case 10 Double Stud Wall with Spray Foam
amp 13 13
) 13 13
)13
amp 13 13
131313
13
13 131313
1313 13 1313 13
13
Figure 48 Double stud wall with 2 of spray foam and cellulose fill
1101 Thermal Control
$) 13
13(amp() $
13$
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 49 Therm analysis of double stud wall construction with spray foam
Table 13 Calculated whole wall R-value for a double stud wall system with 2rdquo spray foam
1102 Moisture Control
13 13 (13
13 13
13 1313 13
13 13
($$13(amp$$$13
13 1313 1313 13 13
13 13 13 $13 13
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1103 Constructability and Cost
13131313 13 13
13131313131313
Building Science Corporation )( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1104 Other Considerations
13 13 13 1313
131313(13 131313 1313 13 amp
13 13 (
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13 (
111 Case 11 Offset Frame Wall with Exterior Spray Foam
131313 1313 13 1313
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13 1313$ 13 13 13(
13 13 13 13 13 13
$ 13 ( 1313 13 131313131313
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(
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30 Forest St Somerville MA 02143
Figure 50 Offset frame wall construction with exterior spray foam
1111 Thermal Control
131313 13 1313131313
1313 131313
13 13 13131313
13 13 13 13 13 13 13
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 51 Therm analysis of an offset truss wall with exterior spray foam
Table 14 Calculated whole wall R-value for an offset framed wall with exterior spray foam
1112 Moisture Control
13
$ 13$
+amp13
+amp$
13 131313
1313 ()amp$13
13 13131313
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1313
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1113 Constructability and Cost
13 $13
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30 Forest St Somerville MA 02143
$($( $$
$ $($$($$+
1114 Other Considerations
$$amp$(amp$+
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ampamp$amp$+
amp$+13 $-
$$(($
112 Case 12 Exterior Insulation Finish System (EIFS)
$(- 13()+
$ $
amp$$+amp$
-016532443405amp(+
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(amp $
$amp(amp$(+
$$ampamp 13$ampamp$(
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Building Science Corporation 25 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 52 Wall construction using the EIFS cladding system
1121 Thermal Control
1313 1313
1313 1313
1313 131313
13 13 $
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 53 Thermal analysis of an EIFS wall system
Table 15 Calculated whole wall R-value for a EIFS wall system with 4rdquo of EPS
1122 Moisture Control
1313131313131313
131313amp1313
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13 13 13+ 13amp 131313
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1123 Constructability and Cost
131313131313
131313amp1313131313amp
131313131313 1313 13
1313amp
1124 Other Considerations
131313131313amp 13
13131313 131313
13amp13$1313131313
1313131313amp 131313131313
131313131313amp
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30 Forest St Somerville MA 02143
D Conclusions
amp 1313
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13131313 1313
1313
Table 16 Summary of all calculated R-values
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30 Forest St Somerville MA 02143
Table 17 Hours of potential winter time air leakage condensation
13
) 1313amp$13
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1313
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1313
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30 Forest St Somerville MA 02143
Table 18 Wall Comparison Chart
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30 Forest St Somerville MA 02143
Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
Figure 30 Therm modeling of Case 1 - 2x6 construction
1313 13 13 131313 (-$13
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131313) )13131313131313(-131313
13131313131313131313
13 13131313131313131313)+
13)-13131313131313 13
13
Table 5 Summary of R-value results from Therm modeling for Case 1
1313131313131313131313
131313 131313 13 13
13 1313131313
1313 1313 131313
13 13 13 13
112 Moisture Control
1313131313 13131313 13
++ +13 1313)+ )- 131313
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
131313
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113 Constructability and Cost
13
amp13
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114 Other Considerations
13
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131+13
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12 Case 2 Advanced framing with insulated sheathing
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30 Forest St Somerville MA 02143
Figure 31 Advanced framing construction
121 Thermal Control
131313 13$13 1313
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1313131313 1313
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1313131313 1313
131313 1313
13131313131313
131313amp1313 13
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 32 Therm modeling of Case 2 advanced framing with 1 XPS insulated sheathing
amp $ $ 13 + 2 3$$35
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Table 6 Summary of R-value results from Therm modeling for Case 2
122 Moisture Control
$
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3$ 76(23$amp (
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Building Science Corporation 00 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
131313$ 1313
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2 131313
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123 Constructability and Cost
131313131313
13130$
13-$131313
131313(13
$$13131313
13 1313
124 Other Considerations
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131313$1313 13
1313
13 Case 3 Interior 2x3 horizontal strapping
13 $
13$
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 33 2x6 wall construction with interior strapping
131 Thermal Control
1313 1313131313
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1313131313 1313
131313 13 13131313
1313 1313131313
1313 1313 1313131313
13131313 13
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 34 Therm analysis of horizontally strapped wall
13$13-amp0)132amp 13$
3-1 1amp13 13
amp 13 13amp
Table 7 Calculated R-value of an interior horizontal strapped wall
132 Moisture Control
13
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13 $amp
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30 Forest St Somerville MA 02143
13 13
133 Constructability and Cost
1313$
13 13
1313
134 Other Considerations
13
131313
13
14 Case 4 Double Stud
1313
131313
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 35 Double stud wall
141 Thermal Control
13
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30 Forest St Somerville MA 02143
13$131313
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)-0 13 13
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Figure 36 Therm model of the double stud wall
Table 8 Calculated R-value of a double stud wall
142 Moisture Control
13131313
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amp13 $$13
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131313
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30 Forest St Somerville MA 02143
13
13)amp 13
13 1313
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143 Constructability and Cost
13
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144 Other Considerations
13 13
131313
13 1313
15 Case 5 Truss Wall
1313
13 13131313
13 13 13
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Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 37 Truss wall construction
151 Thermal Control
1313
13 13(
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)-13
131313
13
13 $)
13 13
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 38 Therm results of the truss wall
Table 9 Calculated R-value for truss wall
152 Moisture Control
13
1313
13 1313
13amp(
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13 13
1313
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13
13 13$13
13
13
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30 Forest St Somerville MA 02143
153 Constructability and Cost
13
13131313
13
13+($13
13
$ 13
154 Other Considerations
13 $$
1313amp
)
16 Case 6 Structural Insulated Panel Systems (SIPs)
131313
13 13$13 13
amp
Figure 39 SIPs wall construction
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
161 Thermal Control
13 13
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)13 $$
$2)6)
13 $ (
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$1302( -
27( $ amp03)4 13
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-0( $)
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Figure 40 Therm results of SIPs panel analysis
Table 10 Calculated R-value for a Sips wall system
162 Moisture Control
13 $ $ amp
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amp
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)
Building Science Corporation 33 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($$
amp$$+$($
163 Constructability and Cost
$amp $$$$ $
()$$(($(
+amp
164 Other Considerations
()($$$((
$) $ $$
$)$amp$amp($
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)(ampamp13+$(amp
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17 Case 7 Insulated Concrete Forms (ICFs)
(amp($
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 41 ICF wall construction
171 Thermal Control
1313
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amp)$)
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 42 Nine inch foam ICF with five inches of EPS
Figure 43 Fifteen inch foam ICF with five inches of EPS
13 13 1313
13 1313131313$13$1313
1313amp1313 13 1313
13131313$amp
172 Moisture Control
1313131313131313 13$amp131313
131313 13amp13
$ 13$1313$13ampamp
13 1313$1313131313
131313amp13
1313131313 13amp
173 Constructability and Cost
13131313 $1313$13$ 13
13 13$1313amp13$13
1313 amp13 13
13 13 1313$
13$13 13$131313
131313 1313 13$amp
174 Other Considerations
13 1313 131313$
13$$131313 1313 13
13amp131313$ 131313
1313 13amp13 131313
Building Science Corporation () wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 1313 13131313 1313 13 13
13 13 1313 13
131313 13131313131313
131313 1313 13 13 1313 13
131313131313 131313
13131313
18 Case 8 Advanced framing with spray foam
13 13 13131313131313
13131313131313 13$
13 $
Figure 44 2x6 wall construction with spray foam insulation
181 Thermal Control
13131313 1313131313 13131313131313
131313131313
Building Science Corporation amp( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13amp13 1313$
13amp
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13-
Figure 45 Therm modeling of spray foam wall and rim joist
13 amp amp+1+
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amp
Table 11 Therm results of spray foam insulation analysis
182 Moisture Control
13 $
1313 13
131313
13
Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313 13 13
13 13 $ 13
131313 23
(+-)$
13 13
1313
13 (+)$
1313 13
1313 3
1313$
1313 13 13
13 1313$
(+) 13 13 1313+-
113 13 13 13
-1313+-$
183 Constructability and Cost
13 13 13 13
$13 13
1313 13 13$
184 Other Considerations
1313
$ 1313
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19 Case 9 Hybrid Wall Insulation ndash Flash and Fill
13 $1313
1313 $13
131313$13 131313
13 13$
1313 13 0amp $
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 46 Hybrid wall construction with 2 spray foam and fibrous fill
191 Thermal Control
131313131313
13 1313 13
$amp $ amp 13
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30 Forest St Somerville MA 02143
Figure 47 Therm analysis of hybrid wall system
Table 12 Calculated R-value for a hybrid wall system
192 Moisture Control
+ amp 13
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13
13 +(
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193 Constructability and Cost
13131313131313
13
1313
194 Other Considerations
1313
1313 1313
1313
Building Science Corporation -+ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 13
13
110 Case 10 Double Stud Wall with Spray Foam
amp 13 13
) 13 13
)13
amp 13 13
131313
13
13 131313
1313 13 1313 13
13
Figure 48 Double stud wall with 2 of spray foam and cellulose fill
1101 Thermal Control
$) 13
13(amp() $
13$
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 49 Therm analysis of double stud wall construction with spray foam
Table 13 Calculated whole wall R-value for a double stud wall system with 2rdquo spray foam
1102 Moisture Control
13 13 (13
13 13
13 1313 13
13 13
($$13(amp$$$13
13 1313 1313 13 13
13 13 13 $13 13
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13 1313 amp
1313 13 13
1103 Constructability and Cost
13131313 13 13
13131313131313
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30 Forest St Somerville MA 02143
1104 Other Considerations
13 13 13 1313
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13 13 (
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13 (
111 Case 11 Offset Frame Wall with Exterior Spray Foam
131313 1313 13 1313
13 13 13 13( 13 1313131313 131313
13 1313$ 13 13 13(
13 13 13 13 13 13
$ 13 ( 1313 13 131313131313
1313 13 13( 1313
13 13 13(
13 13 13 13 13(
1313 ( 1313 13 13
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13 13 13 13 13 13 13 13
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30 Forest St Somerville MA 02143
Figure 50 Offset frame wall construction with exterior spray foam
1111 Thermal Control
131313 13 1313131313
1313 131313
13 13 13131313
13 13 13 13 13 13 13
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 51 Therm analysis of an offset truss wall with exterior spray foam
Table 14 Calculated whole wall R-value for an offset framed wall with exterior spray foam
1112 Moisture Control
13
$ 13$
+amp13
+amp$
13 131313
1313 ()amp$13
13 13131313
1313$
1313
13
(-amp$
1113 Constructability and Cost
13 $13
1313 13 13 $
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($( $$
$ $($$($$+
1114 Other Considerations
$$amp$(amp$+
( $ $(($$
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amp$+13 $-
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112 Case 12 Exterior Insulation Finish System (EIFS)
$(- 13()+
$ $
amp$$+amp$
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(amp $
$amp(amp$(+
$$ampamp 13$ampamp$(
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($$ 13($$+
Building Science Corporation 25 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 52 Wall construction using the EIFS cladding system
1121 Thermal Control
1313 1313
1313 1313
1313 131313
13 13 $
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 53 Thermal analysis of an EIFS wall system
Table 15 Calculated whole wall R-value for a EIFS wall system with 4rdquo of EPS
1122 Moisture Control
1313131313131313
131313amp1313
13131313
131313amp
13131313131313
13 13 13+ 13amp 131313
1313131313 131313) amp
1123 Constructability and Cost
131313131313
131313amp1313131313amp
131313131313 1313 13
1313amp
1124 Other Considerations
131313131313amp 13
13131313 131313
13amp13$1313131313
1313131313amp 131313131313
131313131313amp
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
D Conclusions
amp 1313
)- 13$13
13131313 1313
1313
Table 16 Summary of all calculated R-values
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Building Science Corporation -) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 17 Hours of potential winter time air leakage condensation
13
) 1313amp$13
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amp13amp$13
131313
13
1313
13
1313
Building Science Corporation (amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 18 Wall Comparison Chart
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30 Forest St Somerville MA 02143
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30 Forest St Somerville MA 02143
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Building Science Corporation GF wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
131313
amp 13
2-)0--)04011+amp
113 Constructability and Cost
13
amp13
13amp
114 Other Considerations
13
13amp
131+13
amp 13
13amp
12 Case 2 Advanced framing with insulated sheathing
1313
amp 13131313
amp 3131(ampamp
amp
13amp13
13 13
amp
13amp $
13amp
(1(0+ampamp2(
13
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amp 1313
13amp
Building Science Corporation 0 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 31 Advanced framing construction
121 Thermal Control
131313 13$13 1313
1313 13$13$1313 13
$$)amp $$)13$$13 13) 13
1313131313 1313
131313(-(13$amp-( 1313amp
+(13$13$1313$1313amp13
1313131313 1313
131313 1313
13131313131313
131313amp1313 13
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 32 Therm modeling of Case 2 advanced framing with 1 XPS insulated sheathing
amp $ $ 13 + 2 3$$35
$) 3( -(3 1(2($
$ amp 2($ )
$ ($ $
)13 ( amp amp
3(2 213 (
(
) $ $3(
Table 6 Summary of R-value results from Therm modeling for Case 2
122 Moisture Control
$
$$$
( )
$ (-(2( $
3$ 76(23$amp (
$
amp (4 $ $13
(13
$amp$ amp (
Building Science Corporation 00 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
131313$ 1313
1++-++13
13
13 1313 13
13)-
13
131313 $ )
2 131313
13
123 Constructability and Cost
131313131313
13130$
13-$131313
131313(13
$$13131313
13 1313
124 Other Considerations
amp 1313
1313
1313$ 13 13
131313$1313 13
1313
13 Case 3 Interior 2x3 horizontal strapping
13 $
13$
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 33 2x6 wall construction with interior strapping
131 Thermal Control
1313 1313131313
1313131313 amp
1313131313 1313
131313 13 13131313
1313 1313131313
1313 1313 1313131313
13131313 13
13 13131313$
131313 13
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 34 Therm analysis of horizontally strapped wall
13$13-amp0)132amp 13$
3-1 1amp13 13
amp 13 13amp
Table 7 Calculated R-value of an interior horizontal strapped wall
132 Moisture Control
13
(1313$amp
$ 13)
-amp $$13 13$
$amp
13$ 13$
13 $amp
$
$1++ amp
$ $ 13
amp
$$
13$$++(amp
Building Science Corporation 1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 13
133 Constructability and Cost
1313$
13 13
1313
134 Other Considerations
13
131313
13
14 Case 4 Double Stud
1313
131313
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 35 Double stud wall
141 Thermal Control
13
1313) 13
)13
amp( 1313
13 13
1313
1313
13
13
131313
) 13
13 13
$ 13
1313
1313
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13$131313
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1313 13$ 13131313
1313)13amp
)-0 13 13
amp13 1313$
13amp$1amp(13 13
-amp $
-+ 131313 amp
13$$
1313amp
Figure 36 Therm model of the double stud wall
Table 8 Calculated R-value of a double stud wall
142 Moisture Control
13131313
01313 13
amp13 $$13
1313 1313amp
131313$13
131313
13amp 0++ 13$-
1313$
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Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13
13)amp 13
13 1313
13
13
13(13$)- 13)amp
143 Constructability and Cost
13
amp 13
144 Other Considerations
13 13
131313
13 1313
15 Case 5 Truss Wall
1313
13 13131313
13 13 13
131313amp
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 37 Truss wall construction
151 Thermal Control
1313
13 13(
1313)1313
13 $)13)+
amp
13
1313
)-13
131313
13
13 $)
13 13
13131313
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 38 Therm results of the truss wall
Table 9 Calculated R-value for truss wall
152 Moisture Control
13
1313
13 1313
13amp(
131313
13 13
1313
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13
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13 13$13
13
13
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Building Science Corporation amp$ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
153 Constructability and Cost
13
13131313
13
13+($13
13
$ 13
154 Other Considerations
13 $$
1313amp
)
16 Case 6 Structural Insulated Panel Systems (SIPs)
131313
13 13$13 13
amp
Figure 39 SIPs wall construction
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
161 Thermal Control
13 13
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)13 $$
$2)6)
13 $ (
(( $
)
$1302( -
27( $ amp03)4 13
)$ amp02)5
-0( $)
amp $ (
$( ) $
amp 13$)
Figure 40 Therm results of SIPs panel analysis
Table 10 Calculated R-value for a Sips wall system
162 Moisture Control
13 $ $ amp
$ ) ( 13
amp
-1311) 13 $
)
Building Science Corporation 33 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($$
amp$$+$($
163 Constructability and Cost
$amp $$$$ $
()$$(($(
+amp
164 Other Considerations
()($$$((
$) $ $$
$)$amp$amp($
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)(ampamp13+$(amp
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)($
17 Case 7 Insulated Concrete Forms (ICFs)
(amp($
$$$
$$$
amp)($$
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 41 ICF wall construction
171 Thermal Control
1313
1313 1313
131313 (
+$)$13 13($
amp)$)
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 42 Nine inch foam ICF with five inches of EPS
Figure 43 Fifteen inch foam ICF with five inches of EPS
13 13 1313
13 1313131313$13$1313
1313amp1313 13 1313
13131313$amp
172 Moisture Control
1313131313131313 13$amp131313
131313 13amp13
$ 13$1313$13ampamp
13 1313$1313131313
131313amp13
1313131313 13amp
173 Constructability and Cost
13131313 $1313$13$ 13
13 13$1313amp13$13
1313 amp13 13
13 13 1313$
13$13 13$131313
131313 1313 13$amp
174 Other Considerations
13 1313 131313$
13$$131313 1313 13
13amp131313$ 131313
1313 13amp13 131313
Building Science Corporation () wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 1313 13131313 1313 13 13
13 13 1313 13
131313 13131313131313
131313 1313 13 13 1313 13
131313131313 131313
13131313
18 Case 8 Advanced framing with spray foam
13 13 13131313131313
13131313131313 13$
13 $
Figure 44 2x6 wall construction with spray foam insulation
181 Thermal Control
13131313 1313131313 13131313131313
131313131313
Building Science Corporation amp( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13amp13 1313$
13amp
0$+ $0
13$
$131313
13131313$1313
13-
Figure 45 Therm modeling of spray foam wall and rim joist
13 amp amp+1+
$+ amp
13-amp(1+)13
amp 131
amp
Table 11 Therm results of spray foam insulation analysis
182 Moisture Control
13 $
1313 13
131313
13
Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313 13 13
13 13 $ 13
131313 23
(+-)$
13 13
1313
13 (+)$
1313 13
1313 3
1313$
1313 13 13
13 1313$
(+) 13 13 1313+-
113 13 13 13
-1313+-$
183 Constructability and Cost
13 13 13 13
$13 13
1313 13 13$
184 Other Considerations
1313
$ 1313
13 1313$
19 Case 9 Hybrid Wall Insulation ndash Flash and Fill
13 $1313
1313 $13
131313$13 131313
13 13$
1313 13 0amp $
13 13
13$ 1313
13 $
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 46 Hybrid wall construction with 2 spray foam and fibrous fill
191 Thermal Control
131313131313
13 1313 13
$amp $ amp 13
131313$(
13 13 13 13
1313
Building Science Corporation amp$ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 47 Therm analysis of hybrid wall system
Table 12 Calculated R-value for a hybrid wall system
192 Moisture Control
+ amp 13
$1313
13 $1313 $ 13
13
13 +(
131313
131313)13(
193 Constructability and Cost
13131313131313
13
1313
194 Other Considerations
1313
1313 1313
1313
Building Science Corporation -+ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 13
13
110 Case 10 Double Stud Wall with Spray Foam
amp 13 13
) 13 13
)13
amp 13 13
131313
13
13 131313
1313 13 1313 13
13
Figure 48 Double stud wall with 2 of spray foam and cellulose fill
1101 Thermal Control
$) 13
13(amp() $
13$
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 49 Therm analysis of double stud wall construction with spray foam
Table 13 Calculated whole wall R-value for a double stud wall system with 2rdquo spray foam
1102 Moisture Control
13 13 (13
13 13
13 1313 13
13 13
($$13(amp$$$13
13 1313 1313 13 13
13 13 13 $13 13
1313 amp+ 13
1313 amp1313 13
13 1313 amp
1313 13 13
1103 Constructability and Cost
13131313 13 13
13131313131313
Building Science Corporation )( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1104 Other Considerations
13 13 13 1313
131313(13 131313 1313 13 amp
13 13 (
131313 1313 13 13 13 13
13 (
111 Case 11 Offset Frame Wall with Exterior Spray Foam
131313 1313 13 1313
13 13 13 13( 13 1313131313 131313
13 1313$ 13 13 13(
13 13 13 13 13 13
$ 13 ( 1313 13 131313131313
1313 13 13( 1313
13 13 13(
13 13 13 13 13(
1313 ( 1313 13 13
1313 (1313 13 13 13 1313
1313 13 13( 1313
13 13 13$13 -++13 13
131313 1313 1313(13 13
13 13 13 )13
13 13 13 13 13 13 13 13
(
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 50 Offset frame wall construction with exterior spray foam
1111 Thermal Control
131313 13 1313131313
1313 131313
13 13 13131313
13 13 13 13 13 13 13
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 51 Therm analysis of an offset truss wall with exterior spray foam
Table 14 Calculated whole wall R-value for an offset framed wall with exterior spray foam
1112 Moisture Control
13
$ 13$
+amp13
+amp$
13 131313
1313 ()amp$13
13 13131313
1313$
1313
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1113 Constructability and Cost
13 $13
1313 13 13 $
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($( $$
$ $($$($$+
1114 Other Considerations
$$amp$(amp$+
( $ $(($$
ampamp$amp$+
amp$+13 $-
$$(($
112 Case 12 Exterior Insulation Finish System (EIFS)
$(- 13()+
$ $
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-016532443405amp(+
13$$$$+
(amp $
$amp(amp$(+
$$ampamp 13$ampamp$(
$amp(+($$
amp$$$ $()+
($amp$13$$
($$ 13($$+
Building Science Corporation 25 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 52 Wall construction using the EIFS cladding system
1121 Thermal Control
1313 1313
1313 1313
1313 131313
13 13 $
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 53 Thermal analysis of an EIFS wall system
Table 15 Calculated whole wall R-value for a EIFS wall system with 4rdquo of EPS
1122 Moisture Control
1313131313131313
131313amp1313
13131313
131313amp
13131313131313
13 13 13+ 13amp 131313
1313131313 131313) amp
1123 Constructability and Cost
131313131313
131313amp1313131313amp
131313131313 1313 13
1313amp
1124 Other Considerations
131313131313amp 13
13131313 131313
13amp13$1313131313
1313131313amp 131313131313
131313131313amp
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
D Conclusions
amp 1313
)- 13$13
13131313 1313
1313
Table 16 Summary of all calculated R-values
131313 amp
amp(
13amp 1313
13 ampamp(1313$
13amp) amp
amp13$ 13$
131313 amp )
( 131313$1313$13
amp+( 1313
13$1313$13
amp 13131313
1313131313 13
131313
13 $
) 13
131313$
$13
13
Building Science Corporation -) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 17 Hours of potential winter time air leakage condensation
13
) 1313amp$13
amp 13amp 13)
amp13amp$13
131313
13
1313
13
1313
Building Science Corporation (amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 18 Wall Comparison Chart
$$ 13$$13
$13
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amp$13
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13 13 amp
$13$1313$ 13$
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$ $13$ amp13 $13
13
13 $amp13
13$13 13
$ $ 13amp
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Building Science Corporation +) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313
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13 1313
13
131313 1313
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
E Works Cited
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Building Science Corporation GF wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
Figure 31 Advanced framing construction
121 Thermal Control
131313 13$13 1313
1313 13$13$1313 13
$$)amp $$)13$$13 13) 13
1313131313 1313
131313(-(13$amp-( 1313amp
+(13$13$1313$1313amp13
1313131313 1313
131313 1313
13131313131313
131313amp1313 13
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 32 Therm modeling of Case 2 advanced framing with 1 XPS insulated sheathing
amp $ $ 13 + 2 3$$35
$) 3( -(3 1(2($
$ amp 2($ )
$ ($ $
)13 ( amp amp
3(2 213 (
(
) $ $3(
Table 6 Summary of R-value results from Therm modeling for Case 2
122 Moisture Control
$
$$$
( )
$ (-(2( $
3$ 76(23$amp (
$
amp (4 $ $13
(13
$amp$ amp (
Building Science Corporation 00 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
131313$ 1313
1++-++13
13
13 1313 13
13)-
13
131313 $ )
2 131313
13
123 Constructability and Cost
131313131313
13130$
13-$131313
131313(13
$$13131313
13 1313
124 Other Considerations
amp 1313
1313
1313$ 13 13
131313$1313 13
1313
13 Case 3 Interior 2x3 horizontal strapping
13 $
13$
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 33 2x6 wall construction with interior strapping
131 Thermal Control
1313 1313131313
1313131313 amp
1313131313 1313
131313 13 13131313
1313 1313131313
1313 1313 1313131313
13131313 13
13 13131313$
131313 13
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 34 Therm analysis of horizontally strapped wall
13$13-amp0)132amp 13$
3-1 1amp13 13
amp 13 13amp
Table 7 Calculated R-value of an interior horizontal strapped wall
132 Moisture Control
13
(1313$amp
$ 13)
-amp $$13 13$
$amp
13$ 13$
13 $amp
$
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$ $ 13
amp
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Building Science Corporation 1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 13
133 Constructability and Cost
1313$
13 13
1313
134 Other Considerations
13
131313
13
14 Case 4 Double Stud
1313
131313
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 35 Double stud wall
141 Thermal Control
13
1313) 13
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1313
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13
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13 13
$ 13
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13$131313
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1313)13amp
)-0 13 13
amp13 1313$
13amp$1amp(13 13
-amp $
-+ 131313 amp
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1313amp
Figure 36 Therm model of the double stud wall
Table 8 Calculated R-value of a double stud wall
142 Moisture Control
13131313
01313 13
amp13 $$13
1313 1313amp
131313$13
131313
13amp 0++ 13$-
1313$
13 13)-amp
Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13
13)amp 13
13 1313
13
13
13(13$)- 13)amp
143 Constructability and Cost
13
amp 13
144 Other Considerations
13 13
131313
13 1313
15 Case 5 Truss Wall
1313
13 13131313
13 13 13
131313amp
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 37 Truss wall construction
151 Thermal Control
1313
13 13(
1313)1313
13 $)13)+
amp
13
1313
)-13
131313
13
13 $)
13 13
13131313
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 38 Therm results of the truss wall
Table 9 Calculated R-value for truss wall
152 Moisture Control
13
1313
13 1313
13amp(
131313
13 13
1313
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13
13
13 13$13
13
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Building Science Corporation amp$ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
153 Constructability and Cost
13
13131313
13
13+($13
13
$ 13
154 Other Considerations
13 $$
1313amp
)
16 Case 6 Structural Insulated Panel Systems (SIPs)
131313
13 13$13 13
amp
Figure 39 SIPs wall construction
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
161 Thermal Control
13 13
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)13 $$
$2)6)
13 $ (
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$1302( -
27( $ amp03)4 13
)$ amp02)5
-0( $)
amp $ (
$( ) $
amp 13$)
Figure 40 Therm results of SIPs panel analysis
Table 10 Calculated R-value for a Sips wall system
162 Moisture Control
13 $ $ amp
$ ) ( 13
amp
-1311) 13 $
)
Building Science Corporation 33 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($$
amp$$+$($
163 Constructability and Cost
$amp $$$$ $
()$$(($(
+amp
164 Other Considerations
()($$$((
$) $ $$
$)$amp$amp($
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amp)ampamp13+$$$
)(ampamp13+$(amp
$
- +13amp()$)$
)($
17 Case 7 Insulated Concrete Forms (ICFs)
(amp($
$$$
$$$
amp)($$
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 41 ICF wall construction
171 Thermal Control
1313
1313 1313
131313 (
+$)$13 13($
amp)$)
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 42 Nine inch foam ICF with five inches of EPS
Figure 43 Fifteen inch foam ICF with five inches of EPS
13 13 1313
13 1313131313$13$1313
1313amp1313 13 1313
13131313$amp
172 Moisture Control
1313131313131313 13$amp131313
131313 13amp13
$ 13$1313$13ampamp
13 1313$1313131313
131313amp13
1313131313 13amp
173 Constructability and Cost
13131313 $1313$13$ 13
13 13$1313amp13$13
1313 amp13 13
13 13 1313$
13$13 13$131313
131313 1313 13$amp
174 Other Considerations
13 1313 131313$
13$$131313 1313 13
13amp131313$ 131313
1313 13amp13 131313
Building Science Corporation () wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 1313 13131313 1313 13 13
13 13 1313 13
131313 13131313131313
131313 1313 13 13 1313 13
131313131313 131313
13131313
18 Case 8 Advanced framing with spray foam
13 13 13131313131313
13131313131313 13$
13 $
Figure 44 2x6 wall construction with spray foam insulation
181 Thermal Control
13131313 1313131313 13131313131313
131313131313
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30 Forest St Somerville MA 02143
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Figure 45 Therm modeling of spray foam wall and rim joist
13 amp amp+1+
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Table 11 Therm results of spray foam insulation analysis
182 Moisture Control
13 $
1313 13
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Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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113 13 13 13
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183 Constructability and Cost
13 13 13 13
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184 Other Considerations
1313
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19 Case 9 Hybrid Wall Insulation ndash Flash and Fill
13 $1313
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 46 Hybrid wall construction with 2 spray foam and fibrous fill
191 Thermal Control
131313131313
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30 Forest St Somerville MA 02143
Figure 47 Therm analysis of hybrid wall system
Table 12 Calculated R-value for a hybrid wall system
192 Moisture Control
+ amp 13
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193 Constructability and Cost
13131313131313
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194 Other Considerations
1313
1313 1313
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30 Forest St Somerville MA 02143
13 13
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110 Case 10 Double Stud Wall with Spray Foam
amp 13 13
) 13 13
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13
Figure 48 Double stud wall with 2 of spray foam and cellulose fill
1101 Thermal Control
$) 13
13(amp() $
13$
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 49 Therm analysis of double stud wall construction with spray foam
Table 13 Calculated whole wall R-value for a double stud wall system with 2rdquo spray foam
1102 Moisture Control
13 13 (13
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13 1313 13
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1103 Constructability and Cost
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30 Forest St Somerville MA 02143
1104 Other Considerations
13 13 13 1313
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111 Case 11 Offset Frame Wall with Exterior Spray Foam
131313 1313 13 1313
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30 Forest St Somerville MA 02143
Figure 50 Offset frame wall construction with exterior spray foam
1111 Thermal Control
131313 13 1313131313
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13 13 13 13 13 13 13
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 51 Therm analysis of an offset truss wall with exterior spray foam
Table 14 Calculated whole wall R-value for an offset framed wall with exterior spray foam
1112 Moisture Control
13
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1114 Other Considerations
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112 Case 12 Exterior Insulation Finish System (EIFS)
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30 Forest St Somerville MA 02143
Figure 52 Wall construction using the EIFS cladding system
1121 Thermal Control
1313 1313
1313 1313
1313 131313
13 13 $
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 53 Thermal analysis of an EIFS wall system
Table 15 Calculated whole wall R-value for a EIFS wall system with 4rdquo of EPS
1122 Moisture Control
1313131313131313
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1123 Constructability and Cost
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1124 Other Considerations
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Table 16 Summary of all calculated R-values
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30 Forest St Somerville MA 02143
Table 17 Hours of potential winter time air leakage condensation
13
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30 Forest St Somerville MA 02143
Table 18 Wall Comparison Chart
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Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
Figure 32 Therm modeling of Case 2 advanced framing with 1 XPS insulated sheathing
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Table 6 Summary of R-value results from Therm modeling for Case 2
122 Moisture Control
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123 Constructability and Cost
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13 1313
124 Other Considerations
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13 Case 3 Interior 2x3 horizontal strapping
13 $
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30 Forest St Somerville MA 02143
Figure 33 2x6 wall construction with interior strapping
131 Thermal Control
1313 1313131313
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30 Forest St Somerville MA 02143
Figure 34 Therm analysis of horizontally strapped wall
13$13-amp0)132amp 13$
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Table 7 Calculated R-value of an interior horizontal strapped wall
132 Moisture Control
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13 13
133 Constructability and Cost
1313$
13 13
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134 Other Considerations
13
131313
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14 Case 4 Double Stud
1313
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30 Forest St Somerville MA 02143
Figure 35 Double stud wall
141 Thermal Control
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30 Forest St Somerville MA 02143
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Figure 36 Therm model of the double stud wall
Table 8 Calculated R-value of a double stud wall
142 Moisture Control
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30 Forest St Somerville MA 02143
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143 Constructability and Cost
13
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144 Other Considerations
13 13
131313
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15 Case 5 Truss Wall
1313
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Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 37 Truss wall construction
151 Thermal Control
1313
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30 Forest St Somerville MA 02143
Figure 38 Therm results of the truss wall
Table 9 Calculated R-value for truss wall
152 Moisture Control
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30 Forest St Somerville MA 02143
153 Constructability and Cost
13
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154 Other Considerations
13 $$
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16 Case 6 Structural Insulated Panel Systems (SIPs)
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Figure 39 SIPs wall construction
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
161 Thermal Control
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Figure 40 Therm results of SIPs panel analysis
Table 10 Calculated R-value for a Sips wall system
162 Moisture Control
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Building Science Corporation 33 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($$
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163 Constructability and Cost
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164 Other Considerations
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17 Case 7 Insulated Concrete Forms (ICFs)
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30 Forest St Somerville MA 02143
Figure 41 ICF wall construction
171 Thermal Control
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30 Forest St Somerville MA 02143
Figure 42 Nine inch foam ICF with five inches of EPS
Figure 43 Fifteen inch foam ICF with five inches of EPS
13 13 1313
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172 Moisture Control
1313131313131313 13$amp131313
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173 Constructability and Cost
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174 Other Considerations
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30 Forest St Somerville MA 02143
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13 13 1313 13
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131313 1313 13 13 1313 13
131313131313 131313
13131313
18 Case 8 Advanced framing with spray foam
13 13 13131313131313
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Figure 44 2x6 wall construction with spray foam insulation
181 Thermal Control
13131313 1313131313 13131313131313
131313131313
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30 Forest St Somerville MA 02143
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Figure 45 Therm modeling of spray foam wall and rim joist
13 amp amp+1+
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Table 11 Therm results of spray foam insulation analysis
182 Moisture Control
13 $
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131313
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Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
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113 13 13 13
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183 Constructability and Cost
13 13 13 13
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184 Other Considerations
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19 Case 9 Hybrid Wall Insulation ndash Flash and Fill
13 $1313
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13 13$
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 46 Hybrid wall construction with 2 spray foam and fibrous fill
191 Thermal Control
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13 1313 13
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30 Forest St Somerville MA 02143
Figure 47 Therm analysis of hybrid wall system
Table 12 Calculated R-value for a hybrid wall system
192 Moisture Control
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193 Constructability and Cost
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194 Other Considerations
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30 Forest St Somerville MA 02143
13 13
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110 Case 10 Double Stud Wall with Spray Foam
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13
Figure 48 Double stud wall with 2 of spray foam and cellulose fill
1101 Thermal Control
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13(amp() $
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Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 49 Therm analysis of double stud wall construction with spray foam
Table 13 Calculated whole wall R-value for a double stud wall system with 2rdquo spray foam
1102 Moisture Control
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1103 Constructability and Cost
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30 Forest St Somerville MA 02143
1104 Other Considerations
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111 Case 11 Offset Frame Wall with Exterior Spray Foam
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30 Forest St Somerville MA 02143
Figure 50 Offset frame wall construction with exterior spray foam
1111 Thermal Control
131313 13 1313131313
1313 131313
13 13 13131313
13 13 13 13 13 13 13
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 51 Therm analysis of an offset truss wall with exterior spray foam
Table 14 Calculated whole wall R-value for an offset framed wall with exterior spray foam
1112 Moisture Control
13
$ 13$
+amp13
+amp$
13 131313
1313 ()amp$13
13 13131313
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1113 Constructability and Cost
13 $13
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30 Forest St Somerville MA 02143
$($( $$
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1114 Other Considerations
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112 Case 12 Exterior Insulation Finish System (EIFS)
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30 Forest St Somerville MA 02143
Figure 52 Wall construction using the EIFS cladding system
1121 Thermal Control
1313 1313
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1313 131313
13 13 $
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 53 Thermal analysis of an EIFS wall system
Table 15 Calculated whole wall R-value for a EIFS wall system with 4rdquo of EPS
1122 Moisture Control
1313131313131313
131313amp1313
13131313
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13 13 13+ 13amp 131313
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1123 Constructability and Cost
131313131313
131313amp1313131313amp
131313131313 1313 13
1313amp
1124 Other Considerations
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13131313 131313
13amp13$1313131313
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30 Forest St Somerville MA 02143
D Conclusions
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13131313 1313
1313
Table 16 Summary of all calculated R-values
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30 Forest St Somerville MA 02143
Table 17 Hours of potential winter time air leakage condensation
13
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30 Forest St Somerville MA 02143
Table 18 Wall Comparison Chart
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E Works Cited
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Building Science Corporation GF wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
131313$ 1313
1++-++13
13
13 1313 13
13)-
13
131313 $ )
2 131313
13
123 Constructability and Cost
131313131313
13130$
13-$131313
131313(13
$$13131313
13 1313
124 Other Considerations
amp 1313
1313
1313$ 13 13
131313$1313 13
1313
13 Case 3 Interior 2x3 horizontal strapping
13 $
13$
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 33 2x6 wall construction with interior strapping
131 Thermal Control
1313 1313131313
1313131313 amp
1313131313 1313
131313 13 13131313
1313 1313131313
1313 1313 1313131313
13131313 13
13 13131313$
131313 13
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 34 Therm analysis of horizontally strapped wall
13$13-amp0)132amp 13$
3-1 1amp13 13
amp 13 13amp
Table 7 Calculated R-value of an interior horizontal strapped wall
132 Moisture Control
13
(1313$amp
$ 13)
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$amp
13$ 13$
13 $amp
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Building Science Corporation 1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 13
133 Constructability and Cost
1313$
13 13
1313
134 Other Considerations
13
131313
13
14 Case 4 Double Stud
1313
131313
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 35 Double stud wall
141 Thermal Control
13
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13 13
1313
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13
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13 13
$ 13
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13$131313
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)-0 13 13
amp13 1313$
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Figure 36 Therm model of the double stud wall
Table 8 Calculated R-value of a double stud wall
142 Moisture Control
13131313
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131313$13
131313
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Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13
13)amp 13
13 1313
13
13
13(13$)- 13)amp
143 Constructability and Cost
13
amp 13
144 Other Considerations
13 13
131313
13 1313
15 Case 5 Truss Wall
1313
13 13131313
13 13 13
131313amp
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 37 Truss wall construction
151 Thermal Control
1313
13 13(
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amp
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)-13
131313
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13 $)
13 13
13131313
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 38 Therm results of the truss wall
Table 9 Calculated R-value for truss wall
152 Moisture Control
13
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13 1313
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13
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Building Science Corporation amp$ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
153 Constructability and Cost
13
13131313
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154 Other Considerations
13 $$
1313amp
)
16 Case 6 Structural Insulated Panel Systems (SIPs)
131313
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amp
Figure 39 SIPs wall construction
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
161 Thermal Control
13 13
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13 $ (
(( $
)
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27( $ amp03)4 13
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Figure 40 Therm results of SIPs panel analysis
Table 10 Calculated R-value for a Sips wall system
162 Moisture Control
13 $ $ amp
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amp
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)
Building Science Corporation 33 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($$
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163 Constructability and Cost
$amp $$$$ $
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164 Other Considerations
()($$$((
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17 Case 7 Insulated Concrete Forms (ICFs)
(amp($
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 41 ICF wall construction
171 Thermal Control
1313
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amp)$)
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 42 Nine inch foam ICF with five inches of EPS
Figure 43 Fifteen inch foam ICF with five inches of EPS
13 13 1313
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172 Moisture Control
1313131313131313 13$amp131313
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$ 13$1313$13ampamp
13 1313$1313131313
131313amp13
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173 Constructability and Cost
13131313 $1313$13$ 13
13 13$1313amp13$13
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13$13 13$131313
131313 1313 13$amp
174 Other Considerations
13 1313 131313$
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Building Science Corporation () wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 1313 13131313 1313 13 13
13 13 1313 13
131313 13131313131313
131313 1313 13 13 1313 13
131313131313 131313
13131313
18 Case 8 Advanced framing with spray foam
13 13 13131313131313
13131313131313 13$
13 $
Figure 44 2x6 wall construction with spray foam insulation
181 Thermal Control
13131313 1313131313 13131313131313
131313131313
Building Science Corporation amp( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13amp13 1313$
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$131313
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13-
Figure 45 Therm modeling of spray foam wall and rim joist
13 amp amp+1+
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amp 131
amp
Table 11 Therm results of spray foam insulation analysis
182 Moisture Control
13 $
1313 13
131313
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Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313 13 13
13 13 $ 13
131313 23
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13 13
1313
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1313 13
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1313 13 13
13 1313$
(+) 13 13 1313+-
113 13 13 13
-1313+-$
183 Constructability and Cost
13 13 13 13
$13 13
1313 13 13$
184 Other Considerations
1313
$ 1313
13 1313$
19 Case 9 Hybrid Wall Insulation ndash Flash and Fill
13 $1313
1313 $13
131313$13 131313
13 13$
1313 13 0amp $
13 13
13$ 1313
13 $
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 46 Hybrid wall construction with 2 spray foam and fibrous fill
191 Thermal Control
131313131313
13 1313 13
$amp $ amp 13
131313$(
13 13 13 13
1313
Building Science Corporation amp$ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 47 Therm analysis of hybrid wall system
Table 12 Calculated R-value for a hybrid wall system
192 Moisture Control
+ amp 13
$1313
13 $1313 $ 13
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13 +(
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193 Constructability and Cost
13131313131313
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1313
194 Other Considerations
1313
1313 1313
1313
Building Science Corporation -+ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 13
13
110 Case 10 Double Stud Wall with Spray Foam
amp 13 13
) 13 13
)13
amp 13 13
131313
13
13 131313
1313 13 1313 13
13
Figure 48 Double stud wall with 2 of spray foam and cellulose fill
1101 Thermal Control
$) 13
13(amp() $
13$
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 49 Therm analysis of double stud wall construction with spray foam
Table 13 Calculated whole wall R-value for a double stud wall system with 2rdquo spray foam
1102 Moisture Control
13 13 (13
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13 1313 13
13 13
($$13(amp$$$13
13 1313 1313 13 13
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1103 Constructability and Cost
13131313 13 13
13131313131313
Building Science Corporation )( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1104 Other Considerations
13 13 13 1313
131313(13 131313 1313 13 amp
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111 Case 11 Offset Frame Wall with Exterior Spray Foam
131313 1313 13 1313
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13 13 13 13 13 13
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 50 Offset frame wall construction with exterior spray foam
1111 Thermal Control
131313 13 1313131313
1313 131313
13 13 13131313
13 13 13 13 13 13 13
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 51 Therm analysis of an offset truss wall with exterior spray foam
Table 14 Calculated whole wall R-value for an offset framed wall with exterior spray foam
1112 Moisture Control
13
$ 13$
+amp13
+amp$
13 131313
1313 ()amp$13
13 13131313
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1313
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1113 Constructability and Cost
13 $13
1313 13 13 $
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($( $$
$ $($$($$+
1114 Other Considerations
$$amp$(amp$+
( $ $(($$
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amp$+13 $-
$$(($
112 Case 12 Exterior Insulation Finish System (EIFS)
$(- 13()+
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-016532443405amp(+
13$$$$+
(amp $
$amp(amp$(+
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($$ 13($$+
Building Science Corporation 25 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 52 Wall construction using the EIFS cladding system
1121 Thermal Control
1313 1313
1313 1313
1313 131313
13 13 $
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 53 Thermal analysis of an EIFS wall system
Table 15 Calculated whole wall R-value for a EIFS wall system with 4rdquo of EPS
1122 Moisture Control
1313131313131313
131313amp1313
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1313131313 131313) amp
1123 Constructability and Cost
131313131313
131313amp1313131313amp
131313131313 1313 13
1313amp
1124 Other Considerations
131313131313amp 13
13131313 131313
13amp13$1313131313
1313131313amp 131313131313
131313131313amp
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
D Conclusions
amp 1313
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13131313 1313
1313
Table 16 Summary of all calculated R-values
131313 amp
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1313131313 13
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) 13
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Building Science Corporation -) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 17 Hours of potential winter time air leakage condensation
13
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Building Science Corporation (amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 18 Wall Comparison Chart
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30 Forest St Somerville MA 02143
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30 Forest St Somerville MA 02143
E Works Cited
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Building Science Corporation GF wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
Figure 33 2x6 wall construction with interior strapping
131 Thermal Control
1313 1313131313
1313131313 amp
1313131313 1313
131313 13 13131313
1313 1313131313
1313 1313 1313131313
13131313 13
13 13131313$
131313 13
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 34 Therm analysis of horizontally strapped wall
13$13-amp0)132amp 13$
3-1 1amp13 13
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Table 7 Calculated R-value of an interior horizontal strapped wall
132 Moisture Control
13
(1313$amp
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$amp
13$ 13$
13 $amp
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Building Science Corporation 1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 13
133 Constructability and Cost
1313$
13 13
1313
134 Other Considerations
13
131313
13
14 Case 4 Double Stud
1313
131313
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 35 Double stud wall
141 Thermal Control
13
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1313
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$ 13
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13$131313
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amp13 1313$
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-amp $
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Figure 36 Therm model of the double stud wall
Table 8 Calculated R-value of a double stud wall
142 Moisture Control
13131313
01313 13
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131313$13
131313
13amp 0++ 13$-
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Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13
13)amp 13
13 1313
13
13
13(13$)- 13)amp
143 Constructability and Cost
13
amp 13
144 Other Considerations
13 13
131313
13 1313
15 Case 5 Truss Wall
1313
13 13131313
13 13 13
131313amp
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 37 Truss wall construction
151 Thermal Control
1313
13 13(
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13
1313
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131313
13
13 $)
13 13
13131313
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 38 Therm results of the truss wall
Table 9 Calculated R-value for truss wall
152 Moisture Control
13
1313
13 1313
13amp(
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13 13
1313
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13
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13
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Building Science Corporation amp$ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
153 Constructability and Cost
13
13131313
13
13+($13
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$ 13
154 Other Considerations
13 $$
1313amp
)
16 Case 6 Structural Insulated Panel Systems (SIPs)
131313
13 13$13 13
amp
Figure 39 SIPs wall construction
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
161 Thermal Control
13 13
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13 $ (
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27( $ amp03)4 13
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Figure 40 Therm results of SIPs panel analysis
Table 10 Calculated R-value for a Sips wall system
162 Moisture Control
13 $ $ amp
$ ) ( 13
amp
-1311) 13 $
)
Building Science Corporation 33 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($$
amp$$+$($
163 Constructability and Cost
$amp $$$$ $
()$$(($(
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164 Other Considerations
()($$$((
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17 Case 7 Insulated Concrete Forms (ICFs)
(amp($
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 41 ICF wall construction
171 Thermal Control
1313
1313 1313
131313 (
+$)$13 13($
amp)$)
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 42 Nine inch foam ICF with five inches of EPS
Figure 43 Fifteen inch foam ICF with five inches of EPS
13 13 1313
13 1313131313$13$1313
1313amp1313 13 1313
13131313$amp
172 Moisture Control
1313131313131313 13$amp131313
131313 13amp13
$ 13$1313$13ampamp
13 1313$1313131313
131313amp13
1313131313 13amp
173 Constructability and Cost
13131313 $1313$13$ 13
13 13$1313amp13$13
1313 amp13 13
13 13 1313$
13$13 13$131313
131313 1313 13$amp
174 Other Considerations
13 1313 131313$
13$$131313 1313 13
13amp131313$ 131313
1313 13amp13 131313
Building Science Corporation () wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 1313 13131313 1313 13 13
13 13 1313 13
131313 13131313131313
131313 1313 13 13 1313 13
131313131313 131313
13131313
18 Case 8 Advanced framing with spray foam
13 13 13131313131313
13131313131313 13$
13 $
Figure 44 2x6 wall construction with spray foam insulation
181 Thermal Control
13131313 1313131313 13131313131313
131313131313
Building Science Corporation amp( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13amp13 1313$
13amp
0$+ $0
13$
$131313
13131313$1313
13-
Figure 45 Therm modeling of spray foam wall and rim joist
13 amp amp+1+
$+ amp
13-amp(1+)13
amp 131
amp
Table 11 Therm results of spray foam insulation analysis
182 Moisture Control
13 $
1313 13
131313
13
Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313 13 13
13 13 $ 13
131313 23
(+-)$
13 13
1313
13 (+)$
1313 13
1313 3
1313$
1313 13 13
13 1313$
(+) 13 13 1313+-
113 13 13 13
-1313+-$
183 Constructability and Cost
13 13 13 13
$13 13
1313 13 13$
184 Other Considerations
1313
$ 1313
13 1313$
19 Case 9 Hybrid Wall Insulation ndash Flash and Fill
13 $1313
1313 $13
131313$13 131313
13 13$
1313 13 0amp $
13 13
13$ 1313
13 $
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 46 Hybrid wall construction with 2 spray foam and fibrous fill
191 Thermal Control
131313131313
13 1313 13
$amp $ amp 13
131313$(
13 13 13 13
1313
Building Science Corporation amp$ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 47 Therm analysis of hybrid wall system
Table 12 Calculated R-value for a hybrid wall system
192 Moisture Control
+ amp 13
$1313
13 $1313 $ 13
13
13 +(
131313
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193 Constructability and Cost
13131313131313
13
1313
194 Other Considerations
1313
1313 1313
1313
Building Science Corporation -+ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 13
13
110 Case 10 Double Stud Wall with Spray Foam
amp 13 13
) 13 13
)13
amp 13 13
131313
13
13 131313
1313 13 1313 13
13
Figure 48 Double stud wall with 2 of spray foam and cellulose fill
1101 Thermal Control
$) 13
13(amp() $
13$
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 49 Therm analysis of double stud wall construction with spray foam
Table 13 Calculated whole wall R-value for a double stud wall system with 2rdquo spray foam
1102 Moisture Control
13 13 (13
13 13
13 1313 13
13 13
($$13(amp$$$13
13 1313 1313 13 13
13 13 13 $13 13
1313 amp+ 13
1313 amp1313 13
13 1313 amp
1313 13 13
1103 Constructability and Cost
13131313 13 13
13131313131313
Building Science Corporation )( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1104 Other Considerations
13 13 13 1313
131313(13 131313 1313 13 amp
13 13 (
131313 1313 13 13 13 13
13 (
111 Case 11 Offset Frame Wall with Exterior Spray Foam
131313 1313 13 1313
13 13 13 13( 13 1313131313 131313
13 1313$ 13 13 13(
13 13 13 13 13 13
$ 13 ( 1313 13 131313131313
1313 13 13( 1313
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13 13 13 13 13(
1313 ( 1313 13 13
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131313 1313 1313(13 13
13 13 13 )13
13 13 13 13 13 13 13 13
(
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 50 Offset frame wall construction with exterior spray foam
1111 Thermal Control
131313 13 1313131313
1313 131313
13 13 13131313
13 13 13 13 13 13 13
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 51 Therm analysis of an offset truss wall with exterior spray foam
Table 14 Calculated whole wall R-value for an offset framed wall with exterior spray foam
1112 Moisture Control
13
$ 13$
+amp13
+amp$
13 131313
1313 ()amp$13
13 13131313
1313$
1313
13
(-amp$
1113 Constructability and Cost
13 $13
1313 13 13 $
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($( $$
$ $($$($$+
1114 Other Considerations
$$amp$(amp$+
( $ $(($$
ampamp$amp$+
amp$+13 $-
$$(($
112 Case 12 Exterior Insulation Finish System (EIFS)
$(- 13()+
$ $
amp$$+amp$
-016532443405amp(+
13$$$$+
(amp $
$amp(amp$(+
$$ampamp 13$ampamp$(
$amp(+($$
amp$$$ $()+
($amp$13$$
($$ 13($$+
Building Science Corporation 25 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 52 Wall construction using the EIFS cladding system
1121 Thermal Control
1313 1313
1313 1313
1313 131313
13 13 $
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 53 Thermal analysis of an EIFS wall system
Table 15 Calculated whole wall R-value for a EIFS wall system with 4rdquo of EPS
1122 Moisture Control
1313131313131313
131313amp1313
13131313
131313amp
13131313131313
13 13 13+ 13amp 131313
1313131313 131313) amp
1123 Constructability and Cost
131313131313
131313amp1313131313amp
131313131313 1313 13
1313amp
1124 Other Considerations
131313131313amp 13
13131313 131313
13amp13$1313131313
1313131313amp 131313131313
131313131313amp
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
D Conclusions
amp 1313
)- 13$13
13131313 1313
1313
Table 16 Summary of all calculated R-values
131313 amp
amp(
13amp 1313
13 ampamp(1313$
13amp) amp
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( 131313$1313$13
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1313131313 13
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) 13
131313$
$13
13
Building Science Corporation -) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 17 Hours of potential winter time air leakage condensation
13
) 1313amp$13
amp 13amp 13)
amp13amp$13
131313
13
1313
13
1313
Building Science Corporation (amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 18 Wall Comparison Chart
$$ 13$$13
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13 13 amp
$13$1313$ 13$
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13 $amp13
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30 Forest St Somerville MA 02143
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30 Forest St Somerville MA 02143
E Works Cited
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Building Science Corporation GF wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
Figure 34 Therm analysis of horizontally strapped wall
13$13-amp0)132amp 13$
3-1 1amp13 13
amp 13 13amp
Table 7 Calculated R-value of an interior horizontal strapped wall
132 Moisture Control
13
(1313$amp
$ 13)
-amp $$13 13$
$amp
13$ 13$
13 $amp
$
$1++ amp
$ $ 13
amp
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13$$++(amp
Building Science Corporation 1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 13
133 Constructability and Cost
1313$
13 13
1313
134 Other Considerations
13
131313
13
14 Case 4 Double Stud
1313
131313
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 35 Double stud wall
141 Thermal Control
13
1313) 13
)13
amp( 1313
13 13
1313
1313
13
13
131313
) 13
13 13
$ 13
1313
1313
1313$13
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13$131313
-amp1313
1313 13$ 13131313
1313)13amp
)-0 13 13
amp13 1313$
13amp$1amp(13 13
-amp $
-+ 131313 amp
13$$
1313amp
Figure 36 Therm model of the double stud wall
Table 8 Calculated R-value of a double stud wall
142 Moisture Control
13131313
01313 13
amp13 $$13
1313 1313amp
131313$13
131313
13amp 0++ 13$-
1313$
13 13)-amp
Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13
13)amp 13
13 1313
13
13
13(13$)- 13)amp
143 Constructability and Cost
13
amp 13
144 Other Considerations
13 13
131313
13 1313
15 Case 5 Truss Wall
1313
13 13131313
13 13 13
131313amp
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 37 Truss wall construction
151 Thermal Control
1313
13 13(
1313)1313
13 $)13)+
amp
13
1313
)-13
131313
13
13 $)
13 13
13131313
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 38 Therm results of the truss wall
Table 9 Calculated R-value for truss wall
152 Moisture Control
13
1313
13 1313
13amp(
131313
13 13
1313
13$
13
13
13 13$13
13
13
1313
13
Building Science Corporation amp$ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
153 Constructability and Cost
13
13131313
13
13+($13
13
$ 13
154 Other Considerations
13 $$
1313amp
)
16 Case 6 Structural Insulated Panel Systems (SIPs)
131313
13 13$13 13
amp
Figure 39 SIPs wall construction
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
161 Thermal Control
13 13
-)2)4+(4)4+(6)4+) 13
)13 $$
$2)6)
13 $ (
(( $
)
$1302( -
27( $ amp03)4 13
)$ amp02)5
-0( $)
amp $ (
$( ) $
amp 13$)
Figure 40 Therm results of SIPs panel analysis
Table 10 Calculated R-value for a Sips wall system
162 Moisture Control
13 $ $ amp
$ ) ( 13
amp
-1311) 13 $
)
Building Science Corporation 33 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($$
amp$$+$($
163 Constructability and Cost
$amp $$$$ $
()$$(($(
+amp
164 Other Considerations
()($$$((
$) $ $$
$)$amp$amp($
$)
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amp)ampamp13+$$$
)(ampamp13+$(amp
$
- +13amp()$)$
)($
17 Case 7 Insulated Concrete Forms (ICFs)
(amp($
$$$
$$$
amp)($$
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 41 ICF wall construction
171 Thermal Control
1313
1313 1313
131313 (
+$)$13 13($
amp)$)
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 42 Nine inch foam ICF with five inches of EPS
Figure 43 Fifteen inch foam ICF with five inches of EPS
13 13 1313
13 1313131313$13$1313
1313amp1313 13 1313
13131313$amp
172 Moisture Control
1313131313131313 13$amp131313
131313 13amp13
$ 13$1313$13ampamp
13 1313$1313131313
131313amp13
1313131313 13amp
173 Constructability and Cost
13131313 $1313$13$ 13
13 13$1313amp13$13
1313 amp13 13
13 13 1313$
13$13 13$131313
131313 1313 13$amp
174 Other Considerations
13 1313 131313$
13$$131313 1313 13
13amp131313$ 131313
1313 13amp13 131313
Building Science Corporation () wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 1313 13131313 1313 13 13
13 13 1313 13
131313 13131313131313
131313 1313 13 13 1313 13
131313131313 131313
13131313
18 Case 8 Advanced framing with spray foam
13 13 13131313131313
13131313131313 13$
13 $
Figure 44 2x6 wall construction with spray foam insulation
181 Thermal Control
13131313 1313131313 13131313131313
131313131313
Building Science Corporation amp( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13amp13 1313$
13amp
0$+ $0
13$
$131313
13131313$1313
13-
Figure 45 Therm modeling of spray foam wall and rim joist
13 amp amp+1+
$+ amp
13-amp(1+)13
amp 131
amp
Table 11 Therm results of spray foam insulation analysis
182 Moisture Control
13 $
1313 13
131313
13
Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313 13 13
13 13 $ 13
131313 23
(+-)$
13 13
1313
13 (+)$
1313 13
1313 3
1313$
1313 13 13
13 1313$
(+) 13 13 1313+-
113 13 13 13
-1313+-$
183 Constructability and Cost
13 13 13 13
$13 13
1313 13 13$
184 Other Considerations
1313
$ 1313
13 1313$
19 Case 9 Hybrid Wall Insulation ndash Flash and Fill
13 $1313
1313 $13
131313$13 131313
13 13$
1313 13 0amp $
13 13
13$ 1313
13 $
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 46 Hybrid wall construction with 2 spray foam and fibrous fill
191 Thermal Control
131313131313
13 1313 13
$amp $ amp 13
131313$(
13 13 13 13
1313
Building Science Corporation amp$ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 47 Therm analysis of hybrid wall system
Table 12 Calculated R-value for a hybrid wall system
192 Moisture Control
+ amp 13
$1313
13 $1313 $ 13
13
13 +(
131313
131313)13(
193 Constructability and Cost
13131313131313
13
1313
194 Other Considerations
1313
1313 1313
1313
Building Science Corporation -+ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 13
13
110 Case 10 Double Stud Wall with Spray Foam
amp 13 13
) 13 13
)13
amp 13 13
131313
13
13 131313
1313 13 1313 13
13
Figure 48 Double stud wall with 2 of spray foam and cellulose fill
1101 Thermal Control
$) 13
13(amp() $
13$
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 49 Therm analysis of double stud wall construction with spray foam
Table 13 Calculated whole wall R-value for a double stud wall system with 2rdquo spray foam
1102 Moisture Control
13 13 (13
13 13
13 1313 13
13 13
($$13(amp$$$13
13 1313 1313 13 13
13 13 13 $13 13
1313 amp+ 13
1313 amp1313 13
13 1313 amp
1313 13 13
1103 Constructability and Cost
13131313 13 13
13131313131313
Building Science Corporation )( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1104 Other Considerations
13 13 13 1313
131313(13 131313 1313 13 amp
13 13 (
131313 1313 13 13 13 13
13 (
111 Case 11 Offset Frame Wall with Exterior Spray Foam
131313 1313 13 1313
13 13 13 13( 13 1313131313 131313
13 1313$ 13 13 13(
13 13 13 13 13 13
$ 13 ( 1313 13 131313131313
1313 13 13( 1313
13 13 13(
13 13 13 13 13(
1313 ( 1313 13 13
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1313 13 13( 1313
13 13 13$13 -++13 13
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13 13 13 )13
13 13 13 13 13 13 13 13
(
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 50 Offset frame wall construction with exterior spray foam
1111 Thermal Control
131313 13 1313131313
1313 131313
13 13 13131313
13 13 13 13 13 13 13
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 51 Therm analysis of an offset truss wall with exterior spray foam
Table 14 Calculated whole wall R-value for an offset framed wall with exterior spray foam
1112 Moisture Control
13
$ 13$
+amp13
+amp$
13 131313
1313 ()amp$13
13 13131313
1313$
1313
13
(-amp$
1113 Constructability and Cost
13 $13
1313 13 13 $
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($( $$
$ $($$($$+
1114 Other Considerations
$$amp$(amp$+
( $ $(($$
ampamp$amp$+
amp$+13 $-
$$(($
112 Case 12 Exterior Insulation Finish System (EIFS)
$(- 13()+
$ $
amp$$+amp$
-016532443405amp(+
13$$$$+
(amp $
$amp(amp$(+
$$ampamp 13$ampamp$(
$amp(+($$
amp$$$ $()+
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($$ 13($$+
Building Science Corporation 25 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 52 Wall construction using the EIFS cladding system
1121 Thermal Control
1313 1313
1313 1313
1313 131313
13 13 $
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 53 Thermal analysis of an EIFS wall system
Table 15 Calculated whole wall R-value for a EIFS wall system with 4rdquo of EPS
1122 Moisture Control
1313131313131313
131313amp1313
13131313
131313amp
13131313131313
13 13 13+ 13amp 131313
1313131313 131313) amp
1123 Constructability and Cost
131313131313
131313amp1313131313amp
131313131313 1313 13
1313amp
1124 Other Considerations
131313131313amp 13
13131313 131313
13amp13$1313131313
1313131313amp 131313131313
131313131313amp
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
D Conclusions
amp 1313
)- 13$13
13131313 1313
1313
Table 16 Summary of all calculated R-values
131313 amp
amp(
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13 ampamp(1313$
13amp) amp
amp13$ 13$
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( 131313$1313$13
amp+( 1313
13$1313$13
amp 13131313
1313131313 13
131313
13 $
) 13
131313$
$13
13
Building Science Corporation -) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 17 Hours of potential winter time air leakage condensation
13
) 1313amp$13
amp 13amp 13)
amp13amp$13
131313
13
1313
13
1313
Building Science Corporation (amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 18 Wall Comparison Chart
$$ 13$$13
$13
amp$
amp$13
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13
$ 13 amp amp
13 13 amp
$13$1313$ 13$
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$ $13$ amp13 $13
13
13 $amp13
13$13 13
$ $ 13amp
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Building Science Corporation +) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313
13
13 1313
13
131313 1313
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
E Works Cited
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+amp17 amp7- 7 $$( $+7amp1213 -amp9 $$amp$
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=++13 G7CAAJgt9
279amp+- -ampamp2-$ -+ $amp + -amp$amp+
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- ampamp amp07amp8amp$+ -amp$amp7CAAI9
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+ amp07amp8amp$+ -amp$amp7CAAG9
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CAAF9
Building Science Corporation GF wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
13 13
133 Constructability and Cost
1313$
13 13
1313
134 Other Considerations
13
131313
13
14 Case 4 Double Stud
1313
131313
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 35 Double stud wall
141 Thermal Control
13
1313) 13
)13
amp( 1313
13 13
1313
1313
13
13
131313
) 13
13 13
$ 13
1313
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13$131313
-amp1313
1313 13$ 13131313
1313)13amp
)-0 13 13
amp13 1313$
13amp$1amp(13 13
-amp $
-+ 131313 amp
13$$
1313amp
Figure 36 Therm model of the double stud wall
Table 8 Calculated R-value of a double stud wall
142 Moisture Control
13131313
01313 13
amp13 $$13
1313 1313amp
131313$13
131313
13amp 0++ 13$-
1313$
13 13)-amp
Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13
13)amp 13
13 1313
13
13
13(13$)- 13)amp
143 Constructability and Cost
13
amp 13
144 Other Considerations
13 13
131313
13 1313
15 Case 5 Truss Wall
1313
13 13131313
13 13 13
131313amp
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 37 Truss wall construction
151 Thermal Control
1313
13 13(
1313)1313
13 $)13)+
amp
13
1313
)-13
131313
13
13 $)
13 13
13131313
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 38 Therm results of the truss wall
Table 9 Calculated R-value for truss wall
152 Moisture Control
13
1313
13 1313
13amp(
131313
13 13
1313
13$
13
13
13 13$13
13
13
1313
13
Building Science Corporation amp$ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
153 Constructability and Cost
13
13131313
13
13+($13
13
$ 13
154 Other Considerations
13 $$
1313amp
)
16 Case 6 Structural Insulated Panel Systems (SIPs)
131313
13 13$13 13
amp
Figure 39 SIPs wall construction
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
161 Thermal Control
13 13
-)2)4+(4)4+(6)4+) 13
)13 $$
$2)6)
13 $ (
(( $
)
$1302( -
27( $ amp03)4 13
)$ amp02)5
-0( $)
amp $ (
$( ) $
amp 13$)
Figure 40 Therm results of SIPs panel analysis
Table 10 Calculated R-value for a Sips wall system
162 Moisture Control
13 $ $ amp
$ ) ( 13
amp
-1311) 13 $
)
Building Science Corporation 33 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($$
amp$$+$($
163 Constructability and Cost
$amp $$$$ $
()$$(($(
+amp
164 Other Considerations
()($$$((
$) $ $$
$)$amp$amp($
$)
$$)($amp
amp)ampamp13+$$$
)(ampamp13+$(amp
$
- +13amp()$)$
)($
17 Case 7 Insulated Concrete Forms (ICFs)
(amp($
$$$
$$$
amp)($$
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 41 ICF wall construction
171 Thermal Control
1313
1313 1313
131313 (
+$)$13 13($
amp)$)
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 42 Nine inch foam ICF with five inches of EPS
Figure 43 Fifteen inch foam ICF with five inches of EPS
13 13 1313
13 1313131313$13$1313
1313amp1313 13 1313
13131313$amp
172 Moisture Control
1313131313131313 13$amp131313
131313 13amp13
$ 13$1313$13ampamp
13 1313$1313131313
131313amp13
1313131313 13amp
173 Constructability and Cost
13131313 $1313$13$ 13
13 13$1313amp13$13
1313 amp13 13
13 13 1313$
13$13 13$131313
131313 1313 13$amp
174 Other Considerations
13 1313 131313$
13$$131313 1313 13
13amp131313$ 131313
1313 13amp13 131313
Building Science Corporation () wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 1313 13131313 1313 13 13
13 13 1313 13
131313 13131313131313
131313 1313 13 13 1313 13
131313131313 131313
13131313
18 Case 8 Advanced framing with spray foam
13 13 13131313131313
13131313131313 13$
13 $
Figure 44 2x6 wall construction with spray foam insulation
181 Thermal Control
13131313 1313131313 13131313131313
131313131313
Building Science Corporation amp( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13amp13 1313$
13amp
0$+ $0
13$
$131313
13131313$1313
13-
Figure 45 Therm modeling of spray foam wall and rim joist
13 amp amp+1+
$+ amp
13-amp(1+)13
amp 131
amp
Table 11 Therm results of spray foam insulation analysis
182 Moisture Control
13 $
1313 13
131313
13
Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313 13 13
13 13 $ 13
131313 23
(+-)$
13 13
1313
13 (+)$
1313 13
1313 3
1313$
1313 13 13
13 1313$
(+) 13 13 1313+-
113 13 13 13
-1313+-$
183 Constructability and Cost
13 13 13 13
$13 13
1313 13 13$
184 Other Considerations
1313
$ 1313
13 1313$
19 Case 9 Hybrid Wall Insulation ndash Flash and Fill
13 $1313
1313 $13
131313$13 131313
13 13$
1313 13 0amp $
13 13
13$ 1313
13 $
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 46 Hybrid wall construction with 2 spray foam and fibrous fill
191 Thermal Control
131313131313
13 1313 13
$amp $ amp 13
131313$(
13 13 13 13
1313
Building Science Corporation amp$ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 47 Therm analysis of hybrid wall system
Table 12 Calculated R-value for a hybrid wall system
192 Moisture Control
+ amp 13
$1313
13 $1313 $ 13
13
13 +(
131313
131313)13(
193 Constructability and Cost
13131313131313
13
1313
194 Other Considerations
1313
1313 1313
1313
Building Science Corporation -+ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 13
13
110 Case 10 Double Stud Wall with Spray Foam
amp 13 13
) 13 13
)13
amp 13 13
131313
13
13 131313
1313 13 1313 13
13
Figure 48 Double stud wall with 2 of spray foam and cellulose fill
1101 Thermal Control
$) 13
13(amp() $
13$
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 49 Therm analysis of double stud wall construction with spray foam
Table 13 Calculated whole wall R-value for a double stud wall system with 2rdquo spray foam
1102 Moisture Control
13 13 (13
13 13
13 1313 13
13 13
($$13(amp$$$13
13 1313 1313 13 13
13 13 13 $13 13
1313 amp+ 13
1313 amp1313 13
13 1313 amp
1313 13 13
1103 Constructability and Cost
13131313 13 13
13131313131313
Building Science Corporation )( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1104 Other Considerations
13 13 13 1313
131313(13 131313 1313 13 amp
13 13 (
131313 1313 13 13 13 13
13 (
111 Case 11 Offset Frame Wall with Exterior Spray Foam
131313 1313 13 1313
13 13 13 13( 13 1313131313 131313
13 1313$ 13 13 13(
13 13 13 13 13 13
$ 13 ( 1313 13 131313131313
1313 13 13( 1313
13 13 13(
13 13 13 13 13(
1313 ( 1313 13 13
1313 (1313 13 13 13 1313
1313 13 13( 1313
13 13 13$13 -++13 13
131313 1313 1313(13 13
13 13 13 )13
13 13 13 13 13 13 13 13
(
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 50 Offset frame wall construction with exterior spray foam
1111 Thermal Control
131313 13 1313131313
1313 131313
13 13 13131313
13 13 13 13 13 13 13
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 51 Therm analysis of an offset truss wall with exterior spray foam
Table 14 Calculated whole wall R-value for an offset framed wall with exterior spray foam
1112 Moisture Control
13
$ 13$
+amp13
+amp$
13 131313
1313 ()amp$13
13 13131313
1313$
1313
13
(-amp$
1113 Constructability and Cost
13 $13
1313 13 13 $
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($( $$
$ $($$($$+
1114 Other Considerations
$$amp$(amp$+
( $ $(($$
ampamp$amp$+
amp$+13 $-
$$(($
112 Case 12 Exterior Insulation Finish System (EIFS)
$(- 13()+
$ $
amp$$+amp$
-016532443405amp(+
13$$$$+
(amp $
$amp(amp$(+
$$ampamp 13$ampamp$(
$amp(+($$
amp$$$ $()+
($amp$13$$
($$ 13($$+
Building Science Corporation 25 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 52 Wall construction using the EIFS cladding system
1121 Thermal Control
1313 1313
1313 1313
1313 131313
13 13 $
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 53 Thermal analysis of an EIFS wall system
Table 15 Calculated whole wall R-value for a EIFS wall system with 4rdquo of EPS
1122 Moisture Control
1313131313131313
131313amp1313
13131313
131313amp
13131313131313
13 13 13+ 13amp 131313
1313131313 131313) amp
1123 Constructability and Cost
131313131313
131313amp1313131313amp
131313131313 1313 13
1313amp
1124 Other Considerations
131313131313amp 13
13131313 131313
13amp13$1313131313
1313131313amp 131313131313
131313131313amp
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
D Conclusions
amp 1313
)- 13$13
13131313 1313
1313
Table 16 Summary of all calculated R-values
131313 amp
amp(
13amp 1313
13 ampamp(1313$
13amp) amp
amp13$ 13$
131313 amp )
( 131313$1313$13
amp+( 1313
13$1313$13
amp 13131313
1313131313 13
131313
13 $
) 13
131313$
$13
13
Building Science Corporation -) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 17 Hours of potential winter time air leakage condensation
13
) 1313amp$13
amp 13amp 13)
amp13amp$13
131313
13
1313
13
1313
Building Science Corporation (amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 18 Wall Comparison Chart
$$ 13$$13
$13
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13
$ 13 amp amp
13 13 amp
$13$1313$ 13$
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$ $13$ amp13 $13
13
13 $amp13
13$13 13
$ $ 13amp
amp
Building Science Corporation +) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313
13
13 1313
13
131313 1313
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30 Forest St Somerville MA 02143
E Works Cited
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Building Science Corporation GF wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
Figure 35 Double stud wall
141 Thermal Control
13
1313) 13
)13
amp( 1313
13 13
1313
1313
13
13
131313
) 13
13 13
$ 13
1313
1313
1313$13
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13$131313
-amp1313
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1313)13amp
)-0 13 13
amp13 1313$
13amp$1amp(13 13
-amp $
-+ 131313 amp
13$$
1313amp
Figure 36 Therm model of the double stud wall
Table 8 Calculated R-value of a double stud wall
142 Moisture Control
13131313
01313 13
amp13 $$13
1313 1313amp
131313$13
131313
13amp 0++ 13$-
1313$
13 13)-amp
Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13
13)amp 13
13 1313
13
13
13(13$)- 13)amp
143 Constructability and Cost
13
amp 13
144 Other Considerations
13 13
131313
13 1313
15 Case 5 Truss Wall
1313
13 13131313
13 13 13
131313amp
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 37 Truss wall construction
151 Thermal Control
1313
13 13(
1313)1313
13 $)13)+
amp
13
1313
)-13
131313
13
13 $)
13 13
13131313
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 38 Therm results of the truss wall
Table 9 Calculated R-value for truss wall
152 Moisture Control
13
1313
13 1313
13amp(
131313
13 13
1313
13$
13
13
13 13$13
13
13
1313
13
Building Science Corporation amp$ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
153 Constructability and Cost
13
13131313
13
13+($13
13
$ 13
154 Other Considerations
13 $$
1313amp
)
16 Case 6 Structural Insulated Panel Systems (SIPs)
131313
13 13$13 13
amp
Figure 39 SIPs wall construction
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
161 Thermal Control
13 13
-)2)4+(4)4+(6)4+) 13
)13 $$
$2)6)
13 $ (
(( $
)
$1302( -
27( $ amp03)4 13
)$ amp02)5
-0( $)
amp $ (
$( ) $
amp 13$)
Figure 40 Therm results of SIPs panel analysis
Table 10 Calculated R-value for a Sips wall system
162 Moisture Control
13 $ $ amp
$ ) ( 13
amp
-1311) 13 $
)
Building Science Corporation 33 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($$
amp$$+$($
163 Constructability and Cost
$amp $$$$ $
()$$(($(
+amp
164 Other Considerations
()($$$((
$) $ $$
$)$amp$amp($
$)
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amp)ampamp13+$$$
)(ampamp13+$(amp
$
- +13amp()$)$
)($
17 Case 7 Insulated Concrete Forms (ICFs)
(amp($
$$$
$$$
amp)($$
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 41 ICF wall construction
171 Thermal Control
1313
1313 1313
131313 (
+$)$13 13($
amp)$)
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 42 Nine inch foam ICF with five inches of EPS
Figure 43 Fifteen inch foam ICF with five inches of EPS
13 13 1313
13 1313131313$13$1313
1313amp1313 13 1313
13131313$amp
172 Moisture Control
1313131313131313 13$amp131313
131313 13amp13
$ 13$1313$13ampamp
13 1313$1313131313
131313amp13
1313131313 13amp
173 Constructability and Cost
13131313 $1313$13$ 13
13 13$1313amp13$13
1313 amp13 13
13 13 1313$
13$13 13$131313
131313 1313 13$amp
174 Other Considerations
13 1313 131313$
13$$131313 1313 13
13amp131313$ 131313
1313 13amp13 131313
Building Science Corporation () wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 1313 13131313 1313 13 13
13 13 1313 13
131313 13131313131313
131313 1313 13 13 1313 13
131313131313 131313
13131313
18 Case 8 Advanced framing with spray foam
13 13 13131313131313
13131313131313 13$
13 $
Figure 44 2x6 wall construction with spray foam insulation
181 Thermal Control
13131313 1313131313 13131313131313
131313131313
Building Science Corporation amp( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13amp13 1313$
13amp
0$+ $0
13$
$131313
13131313$1313
13-
Figure 45 Therm modeling of spray foam wall and rim joist
13 amp amp+1+
$+ amp
13-amp(1+)13
amp 131
amp
Table 11 Therm results of spray foam insulation analysis
182 Moisture Control
13 $
1313 13
131313
13
Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313 13 13
13 13 $ 13
131313 23
(+-)$
13 13
1313
13 (+)$
1313 13
1313 3
1313$
1313 13 13
13 1313$
(+) 13 13 1313+-
113 13 13 13
-1313+-$
183 Constructability and Cost
13 13 13 13
$13 13
1313 13 13$
184 Other Considerations
1313
$ 1313
13 1313$
19 Case 9 Hybrid Wall Insulation ndash Flash and Fill
13 $1313
1313 $13
131313$13 131313
13 13$
1313 13 0amp $
13 13
13$ 1313
13 $
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 46 Hybrid wall construction with 2 spray foam and fibrous fill
191 Thermal Control
131313131313
13 1313 13
$amp $ amp 13
131313$(
13 13 13 13
1313
Building Science Corporation amp$ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 47 Therm analysis of hybrid wall system
Table 12 Calculated R-value for a hybrid wall system
192 Moisture Control
+ amp 13
$1313
13 $1313 $ 13
13
13 +(
131313
131313)13(
193 Constructability and Cost
13131313131313
13
1313
194 Other Considerations
1313
1313 1313
1313
Building Science Corporation -+ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 13
13
110 Case 10 Double Stud Wall with Spray Foam
amp 13 13
) 13 13
)13
amp 13 13
131313
13
13 131313
1313 13 1313 13
13
Figure 48 Double stud wall with 2 of spray foam and cellulose fill
1101 Thermal Control
$) 13
13(amp() $
13$
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 49 Therm analysis of double stud wall construction with spray foam
Table 13 Calculated whole wall R-value for a double stud wall system with 2rdquo spray foam
1102 Moisture Control
13 13 (13
13 13
13 1313 13
13 13
($$13(amp$$$13
13 1313 1313 13 13
13 13 13 $13 13
1313 amp+ 13
1313 amp1313 13
13 1313 amp
1313 13 13
1103 Constructability and Cost
13131313 13 13
13131313131313
Building Science Corporation )( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1104 Other Considerations
13 13 13 1313
131313(13 131313 1313 13 amp
13 13 (
131313 1313 13 13 13 13
13 (
111 Case 11 Offset Frame Wall with Exterior Spray Foam
131313 1313 13 1313
13 13 13 13( 13 1313131313 131313
13 1313$ 13 13 13(
13 13 13 13 13 13
$ 13 ( 1313 13 131313131313
1313 13 13( 1313
13 13 13(
13 13 13 13 13(
1313 ( 1313 13 13
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1313 13 13( 1313
13 13 13$13 -++13 13
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13 13 13 )13
13 13 13 13 13 13 13 13
(
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 50 Offset frame wall construction with exterior spray foam
1111 Thermal Control
131313 13 1313131313
1313 131313
13 13 13131313
13 13 13 13 13 13 13
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 51 Therm analysis of an offset truss wall with exterior spray foam
Table 14 Calculated whole wall R-value for an offset framed wall with exterior spray foam
1112 Moisture Control
13
$ 13$
+amp13
+amp$
13 131313
1313 ()amp$13
13 13131313
1313$
1313
13
(-amp$
1113 Constructability and Cost
13 $13
1313 13 13 $
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($( $$
$ $($$($$+
1114 Other Considerations
$$amp$(amp$+
( $ $(($$
ampamp$amp$+
amp$+13 $-
$$(($
112 Case 12 Exterior Insulation Finish System (EIFS)
$(- 13()+
$ $
amp$$+amp$
-016532443405amp(+
13$$$$+
(amp $
$amp(amp$(+
$$ampamp 13$ampamp$(
$amp(+($$
amp$$$ $()+
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($$ 13($$+
Building Science Corporation 25 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 52 Wall construction using the EIFS cladding system
1121 Thermal Control
1313 1313
1313 1313
1313 131313
13 13 $
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 53 Thermal analysis of an EIFS wall system
Table 15 Calculated whole wall R-value for a EIFS wall system with 4rdquo of EPS
1122 Moisture Control
1313131313131313
131313amp1313
13131313
131313amp
13131313131313
13 13 13+ 13amp 131313
1313131313 131313) amp
1123 Constructability and Cost
131313131313
131313amp1313131313amp
131313131313 1313 13
1313amp
1124 Other Considerations
131313131313amp 13
13131313 131313
13amp13$1313131313
1313131313amp 131313131313
131313131313amp
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
D Conclusions
amp 1313
)- 13$13
13131313 1313
1313
Table 16 Summary of all calculated R-values
131313 amp
amp(
13amp 1313
13 ampamp(1313$
13amp) amp
amp13$ 13$
131313 amp )
( 131313$1313$13
amp+( 1313
13$1313$13
amp 13131313
1313131313 13
131313
13 $
) 13
131313$
$13
13
Building Science Corporation -) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 17 Hours of potential winter time air leakage condensation
13
) 1313amp$13
amp 13amp 13)
amp13amp$13
131313
13
1313
13
1313
Building Science Corporation (amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 18 Wall Comparison Chart
$$ 13$$13
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13
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13 13 amp
$13$1313$ 13$
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$ $13$ amp13 $13
13
13 $amp13
13$13 13
$ $ 13amp
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Building Science Corporation +) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313
13
13 1313
13
131313 1313
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
E Works Cited
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- amp79FA9amp($+(($amp amp+-$13+amp1$$9( amp7BJGE9
+amp17 amp7- 7 $$( $+7amp1213 -amp9 $$amp$
amp$-+8$amp+amp-ampampamp$$ $ampampamp
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+-79((0131D7CAAH9 (8ltlt91--9lt M D(A5-M ampamp$(
=++13 G7CAAJgt9
279amp+- -ampamp2-$ -+ $amp + -amp$amp+
$2amp9 (((ampampampamp7-( 1+CJ=CAAHgt8DBBDBC9
-++-7139979139amp713997137amp13913913ampampamp913267113$amp5113)
- ampamp amp07amp8amp$+ -amp$amp7CAAI9
3713999amp4(13)( ) $ amp amp
+ amp07amp8amp$+ -amp$amp7CAAG9
(+amp7$$7ampampampamp$9 1+$(+amp13+-$amp+9amp
7DBDCE913+amp7 8+-+17BJJJ9
9(amp -amp-7$+++-9(( amp( ampamp0-1CAAC9
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$7amp amp7amp amp-913amp )amp amp(amp0$7amp8
$amp$-amp+ amp97CAAG9
-7 amp7amp-amp9( ( amp(amp0+8-$ampamp++7
CAAF9
Building Science Corporation GF wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
13$131313
-amp1313
1313 13$ 13131313
1313)13amp
)-0 13 13
amp13 1313$
13amp$1amp(13 13
-amp $
-+ 131313 amp
13$$
1313amp
Figure 36 Therm model of the double stud wall
Table 8 Calculated R-value of a double stud wall
142 Moisture Control
13131313
01313 13
amp13 $$13
1313 1313amp
131313$13
131313
13amp 0++ 13$-
1313$
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Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13
13)amp 13
13 1313
13
13
13(13$)- 13)amp
143 Constructability and Cost
13
amp 13
144 Other Considerations
13 13
131313
13 1313
15 Case 5 Truss Wall
1313
13 13131313
13 13 13
131313amp
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 37 Truss wall construction
151 Thermal Control
1313
13 13(
1313)1313
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amp
13
1313
)-13
131313
13
13 $)
13 13
13131313
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 38 Therm results of the truss wall
Table 9 Calculated R-value for truss wall
152 Moisture Control
13
1313
13 1313
13amp(
131313
13 13
1313
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13
13
13 13$13
13
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Building Science Corporation amp$ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
153 Constructability and Cost
13
13131313
13
13+($13
13
$ 13
154 Other Considerations
13 $$
1313amp
)
16 Case 6 Structural Insulated Panel Systems (SIPs)
131313
13 13$13 13
amp
Figure 39 SIPs wall construction
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
161 Thermal Control
13 13
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)13 $$
$2)6)
13 $ (
(( $
)
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27( $ amp03)4 13
)$ amp02)5
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amp 13$)
Figure 40 Therm results of SIPs panel analysis
Table 10 Calculated R-value for a Sips wall system
162 Moisture Control
13 $ $ amp
$ ) ( 13
amp
-1311) 13 $
)
Building Science Corporation 33 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($$
amp$$+$($
163 Constructability and Cost
$amp $$$$ $
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+amp
164 Other Considerations
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$) $ $$
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17 Case 7 Insulated Concrete Forms (ICFs)
(amp($
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 41 ICF wall construction
171 Thermal Control
1313
1313 1313
131313 (
+$)$13 13($
amp)$)
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 42 Nine inch foam ICF with five inches of EPS
Figure 43 Fifteen inch foam ICF with five inches of EPS
13 13 1313
13 1313131313$13$1313
1313amp1313 13 1313
13131313$amp
172 Moisture Control
1313131313131313 13$amp131313
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$ 13$1313$13ampamp
13 1313$1313131313
131313amp13
1313131313 13amp
173 Constructability and Cost
13131313 $1313$13$ 13
13 13$1313amp13$13
1313 amp13 13
13 13 1313$
13$13 13$131313
131313 1313 13$amp
174 Other Considerations
13 1313 131313$
13$$131313 1313 13
13amp131313$ 131313
1313 13amp13 131313
Building Science Corporation () wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 1313 13131313 1313 13 13
13 13 1313 13
131313 13131313131313
131313 1313 13 13 1313 13
131313131313 131313
13131313
18 Case 8 Advanced framing with spray foam
13 13 13131313131313
13131313131313 13$
13 $
Figure 44 2x6 wall construction with spray foam insulation
181 Thermal Control
13131313 1313131313 13131313131313
131313131313
Building Science Corporation amp( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13amp13 1313$
13amp
0$+ $0
13$
$131313
13131313$1313
13-
Figure 45 Therm modeling of spray foam wall and rim joist
13 amp amp+1+
$+ amp
13-amp(1+)13
amp 131
amp
Table 11 Therm results of spray foam insulation analysis
182 Moisture Control
13 $
1313 13
131313
13
Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313 13 13
13 13 $ 13
131313 23
(+-)$
13 13
1313
13 (+)$
1313 13
1313 3
1313$
1313 13 13
13 1313$
(+) 13 13 1313+-
113 13 13 13
-1313+-$
183 Constructability and Cost
13 13 13 13
$13 13
1313 13 13$
184 Other Considerations
1313
$ 1313
13 1313$
19 Case 9 Hybrid Wall Insulation ndash Flash and Fill
13 $1313
1313 $13
131313$13 131313
13 13$
1313 13 0amp $
13 13
13$ 1313
13 $
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 46 Hybrid wall construction with 2 spray foam and fibrous fill
191 Thermal Control
131313131313
13 1313 13
$amp $ amp 13
131313$(
13 13 13 13
1313
Building Science Corporation amp$ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 47 Therm analysis of hybrid wall system
Table 12 Calculated R-value for a hybrid wall system
192 Moisture Control
+ amp 13
$1313
13 $1313 $ 13
13
13 +(
131313
131313)13(
193 Constructability and Cost
13131313131313
13
1313
194 Other Considerations
1313
1313 1313
1313
Building Science Corporation -+ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 13
13
110 Case 10 Double Stud Wall with Spray Foam
amp 13 13
) 13 13
)13
amp 13 13
131313
13
13 131313
1313 13 1313 13
13
Figure 48 Double stud wall with 2 of spray foam and cellulose fill
1101 Thermal Control
$) 13
13(amp() $
13$
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 49 Therm analysis of double stud wall construction with spray foam
Table 13 Calculated whole wall R-value for a double stud wall system with 2rdquo spray foam
1102 Moisture Control
13 13 (13
13 13
13 1313 13
13 13
($$13(amp$$$13
13 1313 1313 13 13
13 13 13 $13 13
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1103 Constructability and Cost
13131313 13 13
13131313131313
Building Science Corporation )( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1104 Other Considerations
13 13 13 1313
131313(13 131313 1313 13 amp
13 13 (
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13 (
111 Case 11 Offset Frame Wall with Exterior Spray Foam
131313 1313 13 1313
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13 1313$ 13 13 13(
13 13 13 13 13 13
$ 13 ( 1313 13 131313131313
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30 Forest St Somerville MA 02143
Figure 50 Offset frame wall construction with exterior spray foam
1111 Thermal Control
131313 13 1313131313
1313 131313
13 13 13131313
13 13 13 13 13 13 13
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 51 Therm analysis of an offset truss wall with exterior spray foam
Table 14 Calculated whole wall R-value for an offset framed wall with exterior spray foam
1112 Moisture Control
13
$ 13$
+amp13
+amp$
13 131313
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13 13131313
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1113 Constructability and Cost
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30 Forest St Somerville MA 02143
$($( $$
$ $($$($$+
1114 Other Considerations
$$amp$(amp$+
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$$(($
112 Case 12 Exterior Insulation Finish System (EIFS)
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amp$$+amp$
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(amp $
$amp(amp$(+
$$ampamp 13$ampamp$(
$amp(+($$
amp$$$ $()+
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Building Science Corporation 25 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 52 Wall construction using the EIFS cladding system
1121 Thermal Control
1313 1313
1313 1313
1313 131313
13 13 $
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 53 Thermal analysis of an EIFS wall system
Table 15 Calculated whole wall R-value for a EIFS wall system with 4rdquo of EPS
1122 Moisture Control
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131313amp1313
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13131313131313
13 13 13+ 13amp 131313
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1123 Constructability and Cost
131313131313
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131313131313 1313 13
1313amp
1124 Other Considerations
131313131313amp 13
13131313 131313
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131313131313amp
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
D Conclusions
amp 1313
)- 13$13
13131313 1313
1313
Table 16 Summary of all calculated R-values
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) 13
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Building Science Corporation -) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 17 Hours of potential winter time air leakage condensation
13
) 1313amp$13
amp 13amp 13)
amp13amp$13
131313
13
1313
13
1313
Building Science Corporation (amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 18 Wall Comparison Chart
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30 Forest St Somerville MA 02143
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30 Forest St Somerville MA 02143
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Building Science Corporation GF wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
13
13)amp 13
13 1313
13
13
13(13$)- 13)amp
143 Constructability and Cost
13
amp 13
144 Other Considerations
13 13
131313
13 1313
15 Case 5 Truss Wall
1313
13 13131313
13 13 13
131313amp
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 37 Truss wall construction
151 Thermal Control
1313
13 13(
1313)1313
13 $)13)+
amp
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1313
)-13
131313
13
13 $)
13 13
13131313
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 38 Therm results of the truss wall
Table 9 Calculated R-value for truss wall
152 Moisture Control
13
1313
13 1313
13amp(
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13 13
1313
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13
13
13 13$13
13
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Building Science Corporation amp$ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
153 Constructability and Cost
13
13131313
13
13+($13
13
$ 13
154 Other Considerations
13 $$
1313amp
)
16 Case 6 Structural Insulated Panel Systems (SIPs)
131313
13 13$13 13
amp
Figure 39 SIPs wall construction
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
161 Thermal Control
13 13
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)13 $$
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Figure 40 Therm results of SIPs panel analysis
Table 10 Calculated R-value for a Sips wall system
162 Moisture Control
13 $ $ amp
$ ) ( 13
amp
-1311) 13 $
)
Building Science Corporation 33 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($$
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163 Constructability and Cost
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164 Other Considerations
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17 Case 7 Insulated Concrete Forms (ICFs)
(amp($
$$$
$$$
amp)($$
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 41 ICF wall construction
171 Thermal Control
1313
1313 1313
131313 (
+$)$13 13($
amp)$)
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 42 Nine inch foam ICF with five inches of EPS
Figure 43 Fifteen inch foam ICF with five inches of EPS
13 13 1313
13 1313131313$13$1313
1313amp1313 13 1313
13131313$amp
172 Moisture Control
1313131313131313 13$amp131313
131313 13amp13
$ 13$1313$13ampamp
13 1313$1313131313
131313amp13
1313131313 13amp
173 Constructability and Cost
13131313 $1313$13$ 13
13 13$1313amp13$13
1313 amp13 13
13 13 1313$
13$13 13$131313
131313 1313 13$amp
174 Other Considerations
13 1313 131313$
13$$131313 1313 13
13amp131313$ 131313
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Building Science Corporation () wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 1313 13131313 1313 13 13
13 13 1313 13
131313 13131313131313
131313 1313 13 13 1313 13
131313131313 131313
13131313
18 Case 8 Advanced framing with spray foam
13 13 13131313131313
13131313131313 13$
13 $
Figure 44 2x6 wall construction with spray foam insulation
181 Thermal Control
13131313 1313131313 13131313131313
131313131313
Building Science Corporation amp( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13amp13 1313$
13amp
0$+ $0
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13-
Figure 45 Therm modeling of spray foam wall and rim joist
13 amp amp+1+
$+ amp
13-amp(1+)13
amp 131
amp
Table 11 Therm results of spray foam insulation analysis
182 Moisture Control
13 $
1313 13
131313
13
Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313 13 13
13 13 $ 13
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1313
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1313 13 13
13 1313$
(+) 13 13 1313+-
113 13 13 13
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183 Constructability and Cost
13 13 13 13
$13 13
1313 13 13$
184 Other Considerations
1313
$ 1313
13 1313$
19 Case 9 Hybrid Wall Insulation ndash Flash and Fill
13 $1313
1313 $13
131313$13 131313
13 13$
1313 13 0amp $
13 13
13$ 1313
13 $
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 46 Hybrid wall construction with 2 spray foam and fibrous fill
191 Thermal Control
131313131313
13 1313 13
$amp $ amp 13
131313$(
13 13 13 13
1313
Building Science Corporation amp$ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 47 Therm analysis of hybrid wall system
Table 12 Calculated R-value for a hybrid wall system
192 Moisture Control
+ amp 13
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13 $1313 $ 13
13
13 +(
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193 Constructability and Cost
13131313131313
13
1313
194 Other Considerations
1313
1313 1313
1313
Building Science Corporation -+ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 13
13
110 Case 10 Double Stud Wall with Spray Foam
amp 13 13
) 13 13
)13
amp 13 13
131313
13
13 131313
1313 13 1313 13
13
Figure 48 Double stud wall with 2 of spray foam and cellulose fill
1101 Thermal Control
$) 13
13(amp() $
13$
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 49 Therm analysis of double stud wall construction with spray foam
Table 13 Calculated whole wall R-value for a double stud wall system with 2rdquo spray foam
1102 Moisture Control
13 13 (13
13 13
13 1313 13
13 13
($$13(amp$$$13
13 1313 1313 13 13
13 13 13 $13 13
1313 amp+ 13
1313 amp1313 13
13 1313 amp
1313 13 13
1103 Constructability and Cost
13131313 13 13
13131313131313
Building Science Corporation )( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1104 Other Considerations
13 13 13 1313
131313(13 131313 1313 13 amp
13 13 (
131313 1313 13 13 13 13
13 (
111 Case 11 Offset Frame Wall with Exterior Spray Foam
131313 1313 13 1313
13 13 13 13( 13 1313131313 131313
13 1313$ 13 13 13(
13 13 13 13 13 13
$ 13 ( 1313 13 131313131313
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1313 ( 1313 13 13
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1313 13 13( 1313
13 13 13$13 -++13 13
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13 13 13 13 13 13 13 13
(
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 50 Offset frame wall construction with exterior spray foam
1111 Thermal Control
131313 13 1313131313
1313 131313
13 13 13131313
13 13 13 13 13 13 13
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 51 Therm analysis of an offset truss wall with exterior spray foam
Table 14 Calculated whole wall R-value for an offset framed wall with exterior spray foam
1112 Moisture Control
13
$ 13$
+amp13
+amp$
13 131313
1313 ()amp$13
13 13131313
1313$
1313
13
(-amp$
1113 Constructability and Cost
13 $13
1313 13 13 $
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($( $$
$ $($$($$+
1114 Other Considerations
$$amp$(amp$+
( $ $(($$
ampamp$amp$+
amp$+13 $-
$$(($
112 Case 12 Exterior Insulation Finish System (EIFS)
$(- 13()+
$ $
amp$$+amp$
-016532443405amp(+
13$$$$+
(amp $
$amp(amp$(+
$$ampamp 13$ampamp$(
$amp(+($$
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($$ 13($$+
Building Science Corporation 25 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 52 Wall construction using the EIFS cladding system
1121 Thermal Control
1313 1313
1313 1313
1313 131313
13 13 $
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 53 Thermal analysis of an EIFS wall system
Table 15 Calculated whole wall R-value for a EIFS wall system with 4rdquo of EPS
1122 Moisture Control
1313131313131313
131313amp1313
13131313
131313amp
13131313131313
13 13 13+ 13amp 131313
1313131313 131313) amp
1123 Constructability and Cost
131313131313
131313amp1313131313amp
131313131313 1313 13
1313amp
1124 Other Considerations
131313131313amp 13
13131313 131313
13amp13$1313131313
1313131313amp 131313131313
131313131313amp
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
D Conclusions
amp 1313
)- 13$13
13131313 1313
1313
Table 16 Summary of all calculated R-values
131313 amp
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amp+( 1313
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Building Science Corporation -) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 17 Hours of potential winter time air leakage condensation
13
) 1313amp$13
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amp13amp$13
131313
13
1313
13
1313
Building Science Corporation (amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 18 Wall Comparison Chart
$$ 13$$13
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$13$1313$ 13$
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13
13 $amp13
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$ $ 13amp
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Building Science Corporation +) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313
13
13 1313
13
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Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
E Works Cited
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amp$-+8$amp+amp-ampampamp$$ $ampampamp
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+-79((0131D7CAAH9 (8ltlt91--9lt M D(A5-M ampamp$(
=++13 G7CAAJgt9
279amp+- -ampamp2-$ -+ $amp + -amp$amp+
$2amp9 (((ampampampamp7-( 1+CJ=CAAHgt8DBBDBC9
-++-7139979139amp713997137amp13913913ampampamp913267113$amp5113)
- ampamp amp07amp8amp$+ -amp$amp7CAAI9
3713999amp4(13)( ) $ amp amp
+ amp07amp8amp$+ -amp$amp7CAAG9
(+amp7$$7ampampampamp$9 1+$(+amp13+-$amp+9amp
7DBDCE913+amp7 8+-+17BJJJ9
9(amp -amp-7$+++-9(( amp( ampamp0-1CAAC9
(8ltlt9+(+9ltampamplt amp$ltamp09 MBGB=++ADBA7CAAJgt9
$7amp amp7amp amp-913amp )amp amp(amp0$7amp8
$amp$-amp+ amp97CAAG9
-7 amp7amp-amp9( ( amp(amp0+8-$ampamp++7
CAAF9
Building Science Corporation GF wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
Figure 37 Truss wall construction
151 Thermal Control
1313
13 13(
1313)1313
13 $)13)+
amp
13
1313
)-13
131313
13
13 $)
13 13
13131313
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 38 Therm results of the truss wall
Table 9 Calculated R-value for truss wall
152 Moisture Control
13
1313
13 1313
13amp(
131313
13 13
1313
13$
13
13
13 13$13
13
13
1313
13
Building Science Corporation amp$ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
153 Constructability and Cost
13
13131313
13
13+($13
13
$ 13
154 Other Considerations
13 $$
1313amp
)
16 Case 6 Structural Insulated Panel Systems (SIPs)
131313
13 13$13 13
amp
Figure 39 SIPs wall construction
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
161 Thermal Control
13 13
-)2)4+(4)4+(6)4+) 13
)13 $$
$2)6)
13 $ (
(( $
)
$1302( -
27( $ amp03)4 13
)$ amp02)5
-0( $)
amp $ (
$( ) $
amp 13$)
Figure 40 Therm results of SIPs panel analysis
Table 10 Calculated R-value for a Sips wall system
162 Moisture Control
13 $ $ amp
$ ) ( 13
amp
-1311) 13 $
)
Building Science Corporation 33 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($$
amp$$+$($
163 Constructability and Cost
$amp $$$$ $
()$$(($(
+amp
164 Other Considerations
()($$$((
$) $ $$
$)$amp$amp($
$)
$$)($amp
amp)ampamp13+$$$
)(ampamp13+$(amp
$
- +13amp()$)$
)($
17 Case 7 Insulated Concrete Forms (ICFs)
(amp($
$$$
$$$
amp)($$
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 41 ICF wall construction
171 Thermal Control
1313
1313 1313
131313 (
+$)$13 13($
amp)$)
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 42 Nine inch foam ICF with five inches of EPS
Figure 43 Fifteen inch foam ICF with five inches of EPS
13 13 1313
13 1313131313$13$1313
1313amp1313 13 1313
13131313$amp
172 Moisture Control
1313131313131313 13$amp131313
131313 13amp13
$ 13$1313$13ampamp
13 1313$1313131313
131313amp13
1313131313 13amp
173 Constructability and Cost
13131313 $1313$13$ 13
13 13$1313amp13$13
1313 amp13 13
13 13 1313$
13$13 13$131313
131313 1313 13$amp
174 Other Considerations
13 1313 131313$
13$$131313 1313 13
13amp131313$ 131313
1313 13amp13 131313
Building Science Corporation () wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 1313 13131313 1313 13 13
13 13 1313 13
131313 13131313131313
131313 1313 13 13 1313 13
131313131313 131313
13131313
18 Case 8 Advanced framing with spray foam
13 13 13131313131313
13131313131313 13$
13 $
Figure 44 2x6 wall construction with spray foam insulation
181 Thermal Control
13131313 1313131313 13131313131313
131313131313
Building Science Corporation amp( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13amp13 1313$
13amp
0$+ $0
13$
$131313
13131313$1313
13-
Figure 45 Therm modeling of spray foam wall and rim joist
13 amp amp+1+
$+ amp
13-amp(1+)13
amp 131
amp
Table 11 Therm results of spray foam insulation analysis
182 Moisture Control
13 $
1313 13
131313
13
Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313 13 13
13 13 $ 13
131313 23
(+-)$
13 13
1313
13 (+)$
1313 13
1313 3
1313$
1313 13 13
13 1313$
(+) 13 13 1313+-
113 13 13 13
-1313+-$
183 Constructability and Cost
13 13 13 13
$13 13
1313 13 13$
184 Other Considerations
1313
$ 1313
13 1313$
19 Case 9 Hybrid Wall Insulation ndash Flash and Fill
13 $1313
1313 $13
131313$13 131313
13 13$
1313 13 0amp $
13 13
13$ 1313
13 $
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 46 Hybrid wall construction with 2 spray foam and fibrous fill
191 Thermal Control
131313131313
13 1313 13
$amp $ amp 13
131313$(
13 13 13 13
1313
Building Science Corporation amp$ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 47 Therm analysis of hybrid wall system
Table 12 Calculated R-value for a hybrid wall system
192 Moisture Control
+ amp 13
$1313
13 $1313 $ 13
13
13 +(
131313
131313)13(
193 Constructability and Cost
13131313131313
13
1313
194 Other Considerations
1313
1313 1313
1313
Building Science Corporation -+ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 13
13
110 Case 10 Double Stud Wall with Spray Foam
amp 13 13
) 13 13
)13
amp 13 13
131313
13
13 131313
1313 13 1313 13
13
Figure 48 Double stud wall with 2 of spray foam and cellulose fill
1101 Thermal Control
$) 13
13(amp() $
13$
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 49 Therm analysis of double stud wall construction with spray foam
Table 13 Calculated whole wall R-value for a double stud wall system with 2rdquo spray foam
1102 Moisture Control
13 13 (13
13 13
13 1313 13
13 13
($$13(amp$$$13
13 1313 1313 13 13
13 13 13 $13 13
1313 amp+ 13
1313 amp1313 13
13 1313 amp
1313 13 13
1103 Constructability and Cost
13131313 13 13
13131313131313
Building Science Corporation )( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1104 Other Considerations
13 13 13 1313
131313(13 131313 1313 13 amp
13 13 (
131313 1313 13 13 13 13
13 (
111 Case 11 Offset Frame Wall with Exterior Spray Foam
131313 1313 13 1313
13 13 13 13( 13 1313131313 131313
13 1313$ 13 13 13(
13 13 13 13 13 13
$ 13 ( 1313 13 131313131313
1313 13 13( 1313
13 13 13(
13 13 13 13 13(
1313 ( 1313 13 13
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1313 13 13( 1313
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131313 1313 1313(13 13
13 13 13 )13
13 13 13 13 13 13 13 13
(
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 50 Offset frame wall construction with exterior spray foam
1111 Thermal Control
131313 13 1313131313
1313 131313
13 13 13131313
13 13 13 13 13 13 13
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 51 Therm analysis of an offset truss wall with exterior spray foam
Table 14 Calculated whole wall R-value for an offset framed wall with exterior spray foam
1112 Moisture Control
13
$ 13$
+amp13
+amp$
13 131313
1313 ()amp$13
13 13131313
1313$
1313
13
(-amp$
1113 Constructability and Cost
13 $13
1313 13 13 $
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($( $$
$ $($$($$+
1114 Other Considerations
$$amp$(amp$+
( $ $(($$
ampamp$amp$+
amp$+13 $-
$$(($
112 Case 12 Exterior Insulation Finish System (EIFS)
$(- 13()+
$ $
amp$$+amp$
-016532443405amp(+
13$$$$+
(amp $
$amp(amp$(+
$$ampamp 13$ampamp$(
$amp(+($$
amp$$$ $()+
($amp$13$$
($$ 13($$+
Building Science Corporation 25 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 52 Wall construction using the EIFS cladding system
1121 Thermal Control
1313 1313
1313 1313
1313 131313
13 13 $
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 53 Thermal analysis of an EIFS wall system
Table 15 Calculated whole wall R-value for a EIFS wall system with 4rdquo of EPS
1122 Moisture Control
1313131313131313
131313amp1313
13131313
131313amp
13131313131313
13 13 13+ 13amp 131313
1313131313 131313) amp
1123 Constructability and Cost
131313131313
131313amp1313131313amp
131313131313 1313 13
1313amp
1124 Other Considerations
131313131313amp 13
13131313 131313
13amp13$1313131313
1313131313amp 131313131313
131313131313amp
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
D Conclusions
amp 1313
)- 13$13
13131313 1313
1313
Table 16 Summary of all calculated R-values
131313 amp
amp(
13amp 1313
13 ampamp(1313$
13amp) amp
amp13$ 13$
131313 amp )
( 131313$1313$13
amp+( 1313
13$1313$13
amp 13131313
1313131313 13
131313
13 $
) 13
131313$
$13
13
Building Science Corporation -) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 17 Hours of potential winter time air leakage condensation
13
) 1313amp$13
amp 13amp 13)
amp13amp$13
131313
13
1313
13
1313
Building Science Corporation (amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 18 Wall Comparison Chart
$$ 13$$13
$13
amp$
amp$13
1313
(
1313
$amp ( 13
$( $ (
13
$ 13 amp amp
13 13 amp
$13$1313$ 13$
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$ $13$ amp13 $13
13
13 $amp13
13$13 13
$ $ 13amp
amp
Building Science Corporation +) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313
13
13 1313
13
131313 1313
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
E Works Cited
9ADF8+amp+ 81$$=-amp-7gt9( amp00CAAI9
(8ltlt9-$amp+amp9lt-amp+lt(+lt+(ADF+amp+ 1$$
-amp-lt+ampC +1$$ -+lt+ M KCA -+9
(amp77amp - 9 2ampamp++
+amp$-$amp+913ampamp)327307CAAD9
9$$-+amp+ amp913ampamp 0CAAH9
(8ltlt9 9lt+ LL+ampL$19+(09
+amp77amp +amp19+amp$()-$$amp$900 ) $
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- amp79FA9amp($+(($amp amp+-$13+amp1$$9( amp7BJGE9
+amp17 amp7- 7 $$( $+7amp1213 -amp9 $$amp$
amp$-+8$amp+amp-ampampamp$$ $ampampamp
$$$+9( amp07CAAH9
+-79((0131D7CAAH9 (8ltlt91--9lt M D(A5-M ampamp$(
=++13 G7CAAJgt9
279amp+- -ampamp2-$ -+ $amp + -amp$amp+
$2amp9 (((ampampampamp7-( 1+CJ=CAAHgt8DBBDBC9
-++-7139979139amp713997137amp13913913ampampamp913267113$amp5113)
- ampamp amp07amp8amp$+ -amp$amp7CAAI9
3713999amp4(13)( ) $ amp amp
+ amp07amp8amp$+ -amp$amp7CAAG9
(+amp7$$7ampampampamp$9 1+$(+amp13+-$amp+9amp
7DBDCE913+amp7 8+-+17BJJJ9
9(amp -amp-7$+++-9(( amp( ampamp0-1CAAC9
(8ltlt9+(+9ltampamplt amp$ltamp09 MBGB=++ADBA7CAAJgt9
$7amp amp7amp amp-913amp )amp amp(amp0$7amp8
$amp$-amp+ amp97CAAG9
-7 amp7amp-amp9( ( amp(amp0+8-$ampamp++7
CAAF9
Building Science Corporation GF wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
Figure 38 Therm results of the truss wall
Table 9 Calculated R-value for truss wall
152 Moisture Control
13
1313
13 1313
13amp(
131313
13 13
1313
13$
13
13
13 13$13
13
13
1313
13
Building Science Corporation amp$ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
153 Constructability and Cost
13
13131313
13
13+($13
13
$ 13
154 Other Considerations
13 $$
1313amp
)
16 Case 6 Structural Insulated Panel Systems (SIPs)
131313
13 13$13 13
amp
Figure 39 SIPs wall construction
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
161 Thermal Control
13 13
-)2)4+(4)4+(6)4+) 13
)13 $$
$2)6)
13 $ (
(( $
)
$1302( -
27( $ amp03)4 13
)$ amp02)5
-0( $)
amp $ (
$( ) $
amp 13$)
Figure 40 Therm results of SIPs panel analysis
Table 10 Calculated R-value for a Sips wall system
162 Moisture Control
13 $ $ amp
$ ) ( 13
amp
-1311) 13 $
)
Building Science Corporation 33 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($$
amp$$+$($
163 Constructability and Cost
$amp $$$$ $
()$$(($(
+amp
164 Other Considerations
()($$$((
$) $ $$
$)$amp$amp($
$)
$$)($amp
amp)ampamp13+$$$
)(ampamp13+$(amp
$
- +13amp()$)$
)($
17 Case 7 Insulated Concrete Forms (ICFs)
(amp($
$$$
$$$
amp)($$
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 41 ICF wall construction
171 Thermal Control
1313
1313 1313
131313 (
+$)$13 13($
amp)$)
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 42 Nine inch foam ICF with five inches of EPS
Figure 43 Fifteen inch foam ICF with five inches of EPS
13 13 1313
13 1313131313$13$1313
1313amp1313 13 1313
13131313$amp
172 Moisture Control
1313131313131313 13$amp131313
131313 13amp13
$ 13$1313$13ampamp
13 1313$1313131313
131313amp13
1313131313 13amp
173 Constructability and Cost
13131313 $1313$13$ 13
13 13$1313amp13$13
1313 amp13 13
13 13 1313$
13$13 13$131313
131313 1313 13$amp
174 Other Considerations
13 1313 131313$
13$$131313 1313 13
13amp131313$ 131313
1313 13amp13 131313
Building Science Corporation () wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 1313 13131313 1313 13 13
13 13 1313 13
131313 13131313131313
131313 1313 13 13 1313 13
131313131313 131313
13131313
18 Case 8 Advanced framing with spray foam
13 13 13131313131313
13131313131313 13$
13 $
Figure 44 2x6 wall construction with spray foam insulation
181 Thermal Control
13131313 1313131313 13131313131313
131313131313
Building Science Corporation amp( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13amp13 1313$
13amp
0$+ $0
13$
$131313
13131313$1313
13-
Figure 45 Therm modeling of spray foam wall and rim joist
13 amp amp+1+
$+ amp
13-amp(1+)13
amp 131
amp
Table 11 Therm results of spray foam insulation analysis
182 Moisture Control
13 $
1313 13
131313
13
Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313 13 13
13 13 $ 13
131313 23
(+-)$
13 13
1313
13 (+)$
1313 13
1313 3
1313$
1313 13 13
13 1313$
(+) 13 13 1313+-
113 13 13 13
-1313+-$
183 Constructability and Cost
13 13 13 13
$13 13
1313 13 13$
184 Other Considerations
1313
$ 1313
13 1313$
19 Case 9 Hybrid Wall Insulation ndash Flash and Fill
13 $1313
1313 $13
131313$13 131313
13 13$
1313 13 0amp $
13 13
13$ 1313
13 $
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 46 Hybrid wall construction with 2 spray foam and fibrous fill
191 Thermal Control
131313131313
13 1313 13
$amp $ amp 13
131313$(
13 13 13 13
1313
Building Science Corporation amp$ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 47 Therm analysis of hybrid wall system
Table 12 Calculated R-value for a hybrid wall system
192 Moisture Control
+ amp 13
$1313
13 $1313 $ 13
13
13 +(
131313
131313)13(
193 Constructability and Cost
13131313131313
13
1313
194 Other Considerations
1313
1313 1313
1313
Building Science Corporation -+ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 13
13
110 Case 10 Double Stud Wall with Spray Foam
amp 13 13
) 13 13
)13
amp 13 13
131313
13
13 131313
1313 13 1313 13
13
Figure 48 Double stud wall with 2 of spray foam and cellulose fill
1101 Thermal Control
$) 13
13(amp() $
13$
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 49 Therm analysis of double stud wall construction with spray foam
Table 13 Calculated whole wall R-value for a double stud wall system with 2rdquo spray foam
1102 Moisture Control
13 13 (13
13 13
13 1313 13
13 13
($$13(amp$$$13
13 1313 1313 13 13
13 13 13 $13 13
1313 amp+ 13
1313 amp1313 13
13 1313 amp
1313 13 13
1103 Constructability and Cost
13131313 13 13
13131313131313
Building Science Corporation )( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1104 Other Considerations
13 13 13 1313
131313(13 131313 1313 13 amp
13 13 (
131313 1313 13 13 13 13
13 (
111 Case 11 Offset Frame Wall with Exterior Spray Foam
131313 1313 13 1313
13 13 13 13( 13 1313131313 131313
13 1313$ 13 13 13(
13 13 13 13 13 13
$ 13 ( 1313 13 131313131313
1313 13 13( 1313
13 13 13(
13 13 13 13 13(
1313 ( 1313 13 13
1313 (1313 13 13 13 1313
1313 13 13( 1313
13 13 13$13 -++13 13
131313 1313 1313(13 13
13 13 13 )13
13 13 13 13 13 13 13 13
(
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 50 Offset frame wall construction with exterior spray foam
1111 Thermal Control
131313 13 1313131313
1313 131313
13 13 13131313
13 13 13 13 13 13 13
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 51 Therm analysis of an offset truss wall with exterior spray foam
Table 14 Calculated whole wall R-value for an offset framed wall with exterior spray foam
1112 Moisture Control
13
$ 13$
+amp13
+amp$
13 131313
1313 ()amp$13
13 13131313
1313$
1313
13
(-amp$
1113 Constructability and Cost
13 $13
1313 13 13 $
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($( $$
$ $($$($$+
1114 Other Considerations
$$amp$(amp$+
( $ $(($$
ampamp$amp$+
amp$+13 $-
$$(($
112 Case 12 Exterior Insulation Finish System (EIFS)
$(- 13()+
$ $
amp$$+amp$
-016532443405amp(+
13$$$$+
(amp $
$amp(amp$(+
$$ampamp 13$ampamp$(
$amp(+($$
amp$$$ $()+
($amp$13$$
($$ 13($$+
Building Science Corporation 25 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 52 Wall construction using the EIFS cladding system
1121 Thermal Control
1313 1313
1313 1313
1313 131313
13 13 $
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 53 Thermal analysis of an EIFS wall system
Table 15 Calculated whole wall R-value for a EIFS wall system with 4rdquo of EPS
1122 Moisture Control
1313131313131313
131313amp1313
13131313
131313amp
13131313131313
13 13 13+ 13amp 131313
1313131313 131313) amp
1123 Constructability and Cost
131313131313
131313amp1313131313amp
131313131313 1313 13
1313amp
1124 Other Considerations
131313131313amp 13
13131313 131313
13amp13$1313131313
1313131313amp 131313131313
131313131313amp
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
D Conclusions
amp 1313
)- 13$13
13131313 1313
1313
Table 16 Summary of all calculated R-values
131313 amp
amp(
13amp 1313
13 ampamp(1313$
13amp) amp
amp13$ 13$
131313 amp )
( 131313$1313$13
amp+( 1313
13$1313$13
amp 13131313
1313131313 13
131313
13 $
) 13
131313$
$13
13
Building Science Corporation -) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 17 Hours of potential winter time air leakage condensation
13
) 1313amp$13
amp 13amp 13)
amp13amp$13
131313
13
1313
13
1313
Building Science Corporation (amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 18 Wall Comparison Chart
$$ 13$$13
$13
amp$
amp$13
1313
(
1313
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$( $ (
13
$ 13 amp amp
13 13 amp
$13$1313$ 13$
amp
$ $13$ amp13 $13
13
13 $amp13
13$13 13
$ $ 13amp
amp
Building Science Corporation +) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313
13
13 1313
13
131313 1313
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
E Works Cited
9ADF8+amp+ 81$$=-amp-7gt9( amp00CAAI9
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(amp77amp - 9 2ampamp++
+amp$-$amp+913ampamp)327307CAAD9
9$$-+amp+ amp913ampamp 0CAAH9
(8ltlt9 9lt+ LL+ampL$19+(09
+amp77amp +amp19+amp$()-$$amp$900 ) $
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amp$-+8$amp+amp-ampampamp$$ $ampampamp
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+-79((0131D7CAAH9 (8ltlt91--9lt M D(A5-M ampamp$(
=++13 G7CAAJgt9
279amp+- -ampamp2-$ -+ $amp + -amp$amp+
$2amp9 (((ampampampamp7-( 1+CJ=CAAHgt8DBBDBC9
-++-7139979139amp713997137amp13913913ampampamp913267113$amp5113)
- ampamp amp07amp8amp$+ -amp$amp7CAAI9
3713999amp4(13)( ) $ amp amp
+ amp07amp8amp$+ -amp$amp7CAAG9
(+amp7$$7ampampampamp$9 1+$(+amp13+-$amp+9amp
7DBDCE913+amp7 8+-+17BJJJ9
9(amp -amp-7$+++-9(( amp( ampamp0-1CAAC9
(8ltlt9+(+9ltampamplt amp$ltamp09 MBGB=++ADBA7CAAJgt9
$7amp amp7amp amp-913amp )amp amp(amp0$7amp8
$amp$-amp+ amp97CAAG9
-7 amp7amp-amp9( ( amp(amp0+8-$ampamp++7
CAAF9
Building Science Corporation GF wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
153 Constructability and Cost
13
13131313
13
13+($13
13
$ 13
154 Other Considerations
13 $$
1313amp
)
16 Case 6 Structural Insulated Panel Systems (SIPs)
131313
13 13$13 13
amp
Figure 39 SIPs wall construction
Building Science Corporation + wwwbuildingsciencecom
30 Forest St Somerville MA 02143
161 Thermal Control
13 13
-)2)4+(4)4+(6)4+) 13
)13 $$
$2)6)
13 $ (
(( $
)
$1302( -
27( $ amp03)4 13
)$ amp02)5
-0( $)
amp $ (
$( ) $
amp 13$)
Figure 40 Therm results of SIPs panel analysis
Table 10 Calculated R-value for a Sips wall system
162 Moisture Control
13 $ $ amp
$ ) ( 13
amp
-1311) 13 $
)
Building Science Corporation 33 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($$
amp$$+$($
163 Constructability and Cost
$amp $$$$ $
()$$(($(
+amp
164 Other Considerations
()($$$((
$) $ $$
$)$amp$amp($
$)
$$)($amp
amp)ampamp13+$$$
)(ampamp13+$(amp
$
- +13amp()$)$
)($
17 Case 7 Insulated Concrete Forms (ICFs)
(amp($
$$$
$$$
amp)($$
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 41 ICF wall construction
171 Thermal Control
1313
1313 1313
131313 (
+$)$13 13($
amp)$)
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 42 Nine inch foam ICF with five inches of EPS
Figure 43 Fifteen inch foam ICF with five inches of EPS
13 13 1313
13 1313131313$13$1313
1313amp1313 13 1313
13131313$amp
172 Moisture Control
1313131313131313 13$amp131313
131313 13amp13
$ 13$1313$13ampamp
13 1313$1313131313
131313amp13
1313131313 13amp
173 Constructability and Cost
13131313 $1313$13$ 13
13 13$1313amp13$13
1313 amp13 13
13 13 1313$
13$13 13$131313
131313 1313 13$amp
174 Other Considerations
13 1313 131313$
13$$131313 1313 13
13amp131313$ 131313
1313 13amp13 131313
Building Science Corporation () wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 1313 13131313 1313 13 13
13 13 1313 13
131313 13131313131313
131313 1313 13 13 1313 13
131313131313 131313
13131313
18 Case 8 Advanced framing with spray foam
13 13 13131313131313
13131313131313 13$
13 $
Figure 44 2x6 wall construction with spray foam insulation
181 Thermal Control
13131313 1313131313 13131313131313
131313131313
Building Science Corporation amp( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13amp13 1313$
13amp
0$+ $0
13$
$131313
13131313$1313
13-
Figure 45 Therm modeling of spray foam wall and rim joist
13 amp amp+1+
$+ amp
13-amp(1+)13
amp 131
amp
Table 11 Therm results of spray foam insulation analysis
182 Moisture Control
13 $
1313 13
131313
13
Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313 13 13
13 13 $ 13
131313 23
(+-)$
13 13
1313
13 (+)$
1313 13
1313 3
1313$
1313 13 13
13 1313$
(+) 13 13 1313+-
113 13 13 13
-1313+-$
183 Constructability and Cost
13 13 13 13
$13 13
1313 13 13$
184 Other Considerations
1313
$ 1313
13 1313$
19 Case 9 Hybrid Wall Insulation ndash Flash and Fill
13 $1313
1313 $13
131313$13 131313
13 13$
1313 13 0amp $
13 13
13$ 1313
13 $
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 46 Hybrid wall construction with 2 spray foam and fibrous fill
191 Thermal Control
131313131313
13 1313 13
$amp $ amp 13
131313$(
13 13 13 13
1313
Building Science Corporation amp$ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 47 Therm analysis of hybrid wall system
Table 12 Calculated R-value for a hybrid wall system
192 Moisture Control
+ amp 13
$1313
13 $1313 $ 13
13
13 +(
131313
131313)13(
193 Constructability and Cost
13131313131313
13
1313
194 Other Considerations
1313
1313 1313
1313
Building Science Corporation -+ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 13
13
110 Case 10 Double Stud Wall with Spray Foam
amp 13 13
) 13 13
)13
amp 13 13
131313
13
13 131313
1313 13 1313 13
13
Figure 48 Double stud wall with 2 of spray foam and cellulose fill
1101 Thermal Control
$) 13
13(amp() $
13$
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 49 Therm analysis of double stud wall construction with spray foam
Table 13 Calculated whole wall R-value for a double stud wall system with 2rdquo spray foam
1102 Moisture Control
13 13 (13
13 13
13 1313 13
13 13
($$13(amp$$$13
13 1313 1313 13 13
13 13 13 $13 13
1313 amp+ 13
1313 amp1313 13
13 1313 amp
1313 13 13
1103 Constructability and Cost
13131313 13 13
13131313131313
Building Science Corporation )( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1104 Other Considerations
13 13 13 1313
131313(13 131313 1313 13 amp
13 13 (
131313 1313 13 13 13 13
13 (
111 Case 11 Offset Frame Wall with Exterior Spray Foam
131313 1313 13 1313
13 13 13 13( 13 1313131313 131313
13 1313$ 13 13 13(
13 13 13 13 13 13
$ 13 ( 1313 13 131313131313
1313 13 13( 1313
13 13 13(
13 13 13 13 13(
1313 ( 1313 13 13
1313 (1313 13 13 13 1313
1313 13 13( 1313
13 13 13$13 -++13 13
131313 1313 1313(13 13
13 13 13 )13
13 13 13 13 13 13 13 13
(
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 50 Offset frame wall construction with exterior spray foam
1111 Thermal Control
131313 13 1313131313
1313 131313
13 13 13131313
13 13 13 13 13 13 13
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 51 Therm analysis of an offset truss wall with exterior spray foam
Table 14 Calculated whole wall R-value for an offset framed wall with exterior spray foam
1112 Moisture Control
13
$ 13$
+amp13
+amp$
13 131313
1313 ()amp$13
13 13131313
1313$
1313
13
(-amp$
1113 Constructability and Cost
13 $13
1313 13 13 $
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($( $$
$ $($$($$+
1114 Other Considerations
$$amp$(amp$+
( $ $(($$
ampamp$amp$+
amp$+13 $-
$$(($
112 Case 12 Exterior Insulation Finish System (EIFS)
$(- 13()+
$ $
amp$$+amp$
-016532443405amp(+
13$$$$+
(amp $
$amp(amp$(+
$$ampamp 13$ampamp$(
$amp(+($$
amp$$$ $()+
($amp$13$$
($$ 13($$+
Building Science Corporation 25 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 52 Wall construction using the EIFS cladding system
1121 Thermal Control
1313 1313
1313 1313
1313 131313
13 13 $
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 53 Thermal analysis of an EIFS wall system
Table 15 Calculated whole wall R-value for a EIFS wall system with 4rdquo of EPS
1122 Moisture Control
1313131313131313
131313amp1313
13131313
131313amp
13131313131313
13 13 13+ 13amp 131313
1313131313 131313) amp
1123 Constructability and Cost
131313131313
131313amp1313131313amp
131313131313 1313 13
1313amp
1124 Other Considerations
131313131313amp 13
13131313 131313
13amp13$1313131313
1313131313amp 131313131313
131313131313amp
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
D Conclusions
amp 1313
)- 13$13
13131313 1313
1313
Table 16 Summary of all calculated R-values
131313 amp
amp(
13amp 1313
13 ampamp(1313$
13amp) amp
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131313 amp )
( 131313$1313$13
amp+( 1313
13$1313$13
amp 13131313
1313131313 13
131313
13 $
) 13
131313$
$13
13
Building Science Corporation -) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 17 Hours of potential winter time air leakage condensation
13
) 1313amp$13
amp 13amp 13)
amp13amp$13
131313
13
1313
13
1313
Building Science Corporation (amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 18 Wall Comparison Chart
$$ 13$$13
$13
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amp$13
1313
(
1313
$amp ( 13
$( $ (
13
$ 13 amp amp
13 13 amp
$13$1313$ 13$
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$ $13$ amp13 $13
13
13 $amp13
13$13 13
$ $ 13amp
amp
Building Science Corporation +) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313
13
13 1313
13
131313 1313
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
E Works Cited
9ADF8+amp+ 81$$=-amp-7gt9( amp00CAAI9
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-amp-lt+ampC +1$$ -+lt+ M KCA -+9
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+amp77amp +amp19+amp$()-$$amp$900 ) $
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- amp79FA9amp($+(($amp amp+-$13+amp1$$9( amp7BJGE9
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amp$-+8$amp+amp-ampampamp$$ $ampampamp
$$$+9( amp07CAAH9
+-79((0131D7CAAH9 (8ltlt91--9lt M D(A5-M ampamp$(
=++13 G7CAAJgt9
279amp+- -ampamp2-$ -+ $amp + -amp$amp+
$2amp9 (((ampampampamp7-( 1+CJ=CAAHgt8DBBDBC9
-++-7139979139amp713997137amp13913913ampampamp913267113$amp5113)
- ampamp amp07amp8amp$+ -amp$amp7CAAI9
3713999amp4(13)( ) $ amp amp
+ amp07amp8amp$+ -amp$amp7CAAG9
(+amp7$$7ampampampamp$9 1+$(+amp13+-$amp+9amp
7DBDCE913+amp7 8+-+17BJJJ9
9(amp -amp-7$+++-9(( amp( ampamp0-1CAAC9
(8ltlt9+(+9ltampamplt amp$ltamp09 MBGB=++ADBA7CAAJgt9
$7amp amp7amp amp-913amp )amp amp(amp0$7amp8
$amp$-amp+ amp97CAAG9
-7 amp7amp-amp9( ( amp(amp0+8-$ampamp++7
CAAF9
Building Science Corporation GF wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
161 Thermal Control
13 13
-)2)4+(4)4+(6)4+) 13
)13 $$
$2)6)
13 $ (
(( $
)
$1302( -
27( $ amp03)4 13
)$ amp02)5
-0( $)
amp $ (
$( ) $
amp 13$)
Figure 40 Therm results of SIPs panel analysis
Table 10 Calculated R-value for a Sips wall system
162 Moisture Control
13 $ $ amp
$ ) ( 13
amp
-1311) 13 $
)
Building Science Corporation 33 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($$
amp$$+$($
163 Constructability and Cost
$amp $$$$ $
()$$(($(
+amp
164 Other Considerations
()($$$((
$) $ $$
$)$amp$amp($
$)
$$)($amp
amp)ampamp13+$$$
)(ampamp13+$(amp
$
- +13amp()$)$
)($
17 Case 7 Insulated Concrete Forms (ICFs)
(amp($
$$$
$$$
amp)($$
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 41 ICF wall construction
171 Thermal Control
1313
1313 1313
131313 (
+$)$13 13($
amp)$)
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 42 Nine inch foam ICF with five inches of EPS
Figure 43 Fifteen inch foam ICF with five inches of EPS
13 13 1313
13 1313131313$13$1313
1313amp1313 13 1313
13131313$amp
172 Moisture Control
1313131313131313 13$amp131313
131313 13amp13
$ 13$1313$13ampamp
13 1313$1313131313
131313amp13
1313131313 13amp
173 Constructability and Cost
13131313 $1313$13$ 13
13 13$1313amp13$13
1313 amp13 13
13 13 1313$
13$13 13$131313
131313 1313 13$amp
174 Other Considerations
13 1313 131313$
13$$131313 1313 13
13amp131313$ 131313
1313 13amp13 131313
Building Science Corporation () wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 1313 13131313 1313 13 13
13 13 1313 13
131313 13131313131313
131313 1313 13 13 1313 13
131313131313 131313
13131313
18 Case 8 Advanced framing with spray foam
13 13 13131313131313
13131313131313 13$
13 $
Figure 44 2x6 wall construction with spray foam insulation
181 Thermal Control
13131313 1313131313 13131313131313
131313131313
Building Science Corporation amp( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13amp13 1313$
13amp
0$+ $0
13$
$131313
13131313$1313
13-
Figure 45 Therm modeling of spray foam wall and rim joist
13 amp amp+1+
$+ amp
13-amp(1+)13
amp 131
amp
Table 11 Therm results of spray foam insulation analysis
182 Moisture Control
13 $
1313 13
131313
13
Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313 13 13
13 13 $ 13
131313 23
(+-)$
13 13
1313
13 (+)$
1313 13
1313 3
1313$
1313 13 13
13 1313$
(+) 13 13 1313+-
113 13 13 13
-1313+-$
183 Constructability and Cost
13 13 13 13
$13 13
1313 13 13$
184 Other Considerations
1313
$ 1313
13 1313$
19 Case 9 Hybrid Wall Insulation ndash Flash and Fill
13 $1313
1313 $13
131313$13 131313
13 13$
1313 13 0amp $
13 13
13$ 1313
13 $
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 46 Hybrid wall construction with 2 spray foam and fibrous fill
191 Thermal Control
131313131313
13 1313 13
$amp $ amp 13
131313$(
13 13 13 13
1313
Building Science Corporation amp$ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 47 Therm analysis of hybrid wall system
Table 12 Calculated R-value for a hybrid wall system
192 Moisture Control
+ amp 13
$1313
13 $1313 $ 13
13
13 +(
131313
131313)13(
193 Constructability and Cost
13131313131313
13
1313
194 Other Considerations
1313
1313 1313
1313
Building Science Corporation -+ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 13
13
110 Case 10 Double Stud Wall with Spray Foam
amp 13 13
) 13 13
)13
amp 13 13
131313
13
13 131313
1313 13 1313 13
13
Figure 48 Double stud wall with 2 of spray foam and cellulose fill
1101 Thermal Control
$) 13
13(amp() $
13$
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 49 Therm analysis of double stud wall construction with spray foam
Table 13 Calculated whole wall R-value for a double stud wall system with 2rdquo spray foam
1102 Moisture Control
13 13 (13
13 13
13 1313 13
13 13
($$13(amp$$$13
13 1313 1313 13 13
13 13 13 $13 13
1313 amp+ 13
1313 amp1313 13
13 1313 amp
1313 13 13
1103 Constructability and Cost
13131313 13 13
13131313131313
Building Science Corporation )( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1104 Other Considerations
13 13 13 1313
131313(13 131313 1313 13 amp
13 13 (
131313 1313 13 13 13 13
13 (
111 Case 11 Offset Frame Wall with Exterior Spray Foam
131313 1313 13 1313
13 13 13 13( 13 1313131313 131313
13 1313$ 13 13 13(
13 13 13 13 13 13
$ 13 ( 1313 13 131313131313
1313 13 13( 1313
13 13 13(
13 13 13 13 13(
1313 ( 1313 13 13
1313 (1313 13 13 13 1313
1313 13 13( 1313
13 13 13$13 -++13 13
131313 1313 1313(13 13
13 13 13 )13
13 13 13 13 13 13 13 13
(
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 50 Offset frame wall construction with exterior spray foam
1111 Thermal Control
131313 13 1313131313
1313 131313
13 13 13131313
13 13 13 13 13 13 13
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 51 Therm analysis of an offset truss wall with exterior spray foam
Table 14 Calculated whole wall R-value for an offset framed wall with exterior spray foam
1112 Moisture Control
13
$ 13$
+amp13
+amp$
13 131313
1313 ()amp$13
13 13131313
1313$
1313
13
(-amp$
1113 Constructability and Cost
13 $13
1313 13 13 $
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($( $$
$ $($$($$+
1114 Other Considerations
$$amp$(amp$+
( $ $(($$
ampamp$amp$+
amp$+13 $-
$$(($
112 Case 12 Exterior Insulation Finish System (EIFS)
$(- 13()+
$ $
amp$$+amp$
-016532443405amp(+
13$$$$+
(amp $
$amp(amp$(+
$$ampamp 13$ampamp$(
$amp(+($$
amp$$$ $()+
($amp$13$$
($$ 13($$+
Building Science Corporation 25 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 52 Wall construction using the EIFS cladding system
1121 Thermal Control
1313 1313
1313 1313
1313 131313
13 13 $
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 53 Thermal analysis of an EIFS wall system
Table 15 Calculated whole wall R-value for a EIFS wall system with 4rdquo of EPS
1122 Moisture Control
1313131313131313
131313amp1313
13131313
131313amp
13131313131313
13 13 13+ 13amp 131313
1313131313 131313) amp
1123 Constructability and Cost
131313131313
131313amp1313131313amp
131313131313 1313 13
1313amp
1124 Other Considerations
131313131313amp 13
13131313 131313
13amp13$1313131313
1313131313amp 131313131313
131313131313amp
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
D Conclusions
amp 1313
)- 13$13
13131313 1313
1313
Table 16 Summary of all calculated R-values
131313 amp
amp(
13amp 1313
13 ampamp(1313$
13amp) amp
amp13$ 13$
131313 amp )
( 131313$1313$13
amp+( 1313
13$1313$13
amp 13131313
1313131313 13
131313
13 $
) 13
131313$
$13
13
Building Science Corporation -) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 17 Hours of potential winter time air leakage condensation
13
) 1313amp$13
amp 13amp 13)
amp13amp$13
131313
13
1313
13
1313
Building Science Corporation (amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 18 Wall Comparison Chart
$$ 13$$13
$13
amp$
amp$13
1313
(
1313
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$( $ (
13
$ 13 amp amp
13 13 amp
$13$1313$ 13$
amp
$ $13$ amp13 $13
13
13 $amp13
13$13 13
$ $ 13amp
amp
Building Science Corporation +) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313
13
13 1313
13
131313 1313
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
E Works Cited
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-++-7139979139amp713997137amp13913913ampampamp913267113$amp5113)
- ampamp amp07amp8amp$+ -amp$amp7CAAI9
3713999amp4(13)( ) $ amp amp
+ amp07amp8amp$+ -amp$amp7CAAG9
(+amp7$$7ampampampamp$9 1+$(+amp13+-$amp+9amp
7DBDCE913+amp7 8+-+17BJJJ9
9(amp -amp-7$+++-9(( amp( ampamp0-1CAAC9
(8ltlt9+(+9ltampamplt amp$ltamp09 MBGB=++ADBA7CAAJgt9
$7amp amp7amp amp-913amp )amp amp(amp0$7amp8
$amp$-amp+ amp97CAAG9
-7 amp7amp-amp9( ( amp(amp0+8-$ampamp++7
CAAF9
Building Science Corporation GF wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
$($$
amp$$+$($
163 Constructability and Cost
$amp $$$$ $
()$$(($(
+amp
164 Other Considerations
()($$$((
$) $ $$
$)$amp$amp($
$)
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amp)ampamp13+$$$
)(ampamp13+$(amp
$
- +13amp()$)$
)($
17 Case 7 Insulated Concrete Forms (ICFs)
(amp($
$$$
$$$
amp)($$
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 41 ICF wall construction
171 Thermal Control
1313
1313 1313
131313 (
+$)$13 13($
amp)$)
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 42 Nine inch foam ICF with five inches of EPS
Figure 43 Fifteen inch foam ICF with five inches of EPS
13 13 1313
13 1313131313$13$1313
1313amp1313 13 1313
13131313$amp
172 Moisture Control
1313131313131313 13$amp131313
131313 13amp13
$ 13$1313$13ampamp
13 1313$1313131313
131313amp13
1313131313 13amp
173 Constructability and Cost
13131313 $1313$13$ 13
13 13$1313amp13$13
1313 amp13 13
13 13 1313$
13$13 13$131313
131313 1313 13$amp
174 Other Considerations
13 1313 131313$
13$$131313 1313 13
13amp131313$ 131313
1313 13amp13 131313
Building Science Corporation () wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 1313 13131313 1313 13 13
13 13 1313 13
131313 13131313131313
131313 1313 13 13 1313 13
131313131313 131313
13131313
18 Case 8 Advanced framing with spray foam
13 13 13131313131313
13131313131313 13$
13 $
Figure 44 2x6 wall construction with spray foam insulation
181 Thermal Control
13131313 1313131313 13131313131313
131313131313
Building Science Corporation amp( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13amp13 1313$
13amp
0$+ $0
13$
$131313
13131313$1313
13-
Figure 45 Therm modeling of spray foam wall and rim joist
13 amp amp+1+
$+ amp
13-amp(1+)13
amp 131
amp
Table 11 Therm results of spray foam insulation analysis
182 Moisture Control
13 $
1313 13
131313
13
Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313 13 13
13 13 $ 13
131313 23
(+-)$
13 13
1313
13 (+)$
1313 13
1313 3
1313$
1313 13 13
13 1313$
(+) 13 13 1313+-
113 13 13 13
-1313+-$
183 Constructability and Cost
13 13 13 13
$13 13
1313 13 13$
184 Other Considerations
1313
$ 1313
13 1313$
19 Case 9 Hybrid Wall Insulation ndash Flash and Fill
13 $1313
1313 $13
131313$13 131313
13 13$
1313 13 0amp $
13 13
13$ 1313
13 $
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 46 Hybrid wall construction with 2 spray foam and fibrous fill
191 Thermal Control
131313131313
13 1313 13
$amp $ amp 13
131313$(
13 13 13 13
1313
Building Science Corporation amp$ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 47 Therm analysis of hybrid wall system
Table 12 Calculated R-value for a hybrid wall system
192 Moisture Control
+ amp 13
$1313
13 $1313 $ 13
13
13 +(
131313
131313)13(
193 Constructability and Cost
13131313131313
13
1313
194 Other Considerations
1313
1313 1313
1313
Building Science Corporation -+ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 13
13
110 Case 10 Double Stud Wall with Spray Foam
amp 13 13
) 13 13
)13
amp 13 13
131313
13
13 131313
1313 13 1313 13
13
Figure 48 Double stud wall with 2 of spray foam and cellulose fill
1101 Thermal Control
$) 13
13(amp() $
13$
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 49 Therm analysis of double stud wall construction with spray foam
Table 13 Calculated whole wall R-value for a double stud wall system with 2rdquo spray foam
1102 Moisture Control
13 13 (13
13 13
13 1313 13
13 13
($$13(amp$$$13
13 1313 1313 13 13
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1313 amp1313 13
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1103 Constructability and Cost
13131313 13 13
13131313131313
Building Science Corporation )( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1104 Other Considerations
13 13 13 1313
131313(13 131313 1313 13 amp
13 13 (
131313 1313 13 13 13 13
13 (
111 Case 11 Offset Frame Wall with Exterior Spray Foam
131313 1313 13 1313
13 13 13 13( 13 1313131313 131313
13 1313$ 13 13 13(
13 13 13 13 13 13
$ 13 ( 1313 13 131313131313
1313 13 13( 1313
13 13 13(
13 13 13 13 13(
1313 ( 1313 13 13
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13 13 13 13 13 13 13 13
(
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 50 Offset frame wall construction with exterior spray foam
1111 Thermal Control
131313 13 1313131313
1313 131313
13 13 13131313
13 13 13 13 13 13 13
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 51 Therm analysis of an offset truss wall with exterior spray foam
Table 14 Calculated whole wall R-value for an offset framed wall with exterior spray foam
1112 Moisture Control
13
$ 13$
+amp13
+amp$
13 131313
1313 ()amp$13
13 13131313
1313$
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1113 Constructability and Cost
13 $13
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Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($( $$
$ $($$($$+
1114 Other Considerations
$$amp$(amp$+
( $ $(($$
ampamp$amp$+
amp$+13 $-
$$(($
112 Case 12 Exterior Insulation Finish System (EIFS)
$(- 13()+
$ $
amp$$+amp$
-016532443405amp(+
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(amp $
$amp(amp$(+
$$ampamp 13$ampamp$(
$amp(+($$
amp$$$ $()+
($amp$13$$
($$ 13($$+
Building Science Corporation 25 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 52 Wall construction using the EIFS cladding system
1121 Thermal Control
1313 1313
1313 1313
1313 131313
13 13 $
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 53 Thermal analysis of an EIFS wall system
Table 15 Calculated whole wall R-value for a EIFS wall system with 4rdquo of EPS
1122 Moisture Control
1313131313131313
131313amp1313
13131313
131313amp
13131313131313
13 13 13+ 13amp 131313
1313131313 131313) amp
1123 Constructability and Cost
131313131313
131313amp1313131313amp
131313131313 1313 13
1313amp
1124 Other Considerations
131313131313amp 13
13131313 131313
13amp13$1313131313
1313131313amp 131313131313
131313131313amp
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
D Conclusions
amp 1313
)- 13$13
13131313 1313
1313
Table 16 Summary of all calculated R-values
131313 amp
amp(
13amp 1313
13 ampamp(1313$
13amp) amp
amp13$ 13$
131313 amp )
( 131313$1313$13
amp+( 1313
13$1313$13
amp 13131313
1313131313 13
131313
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) 13
131313$
$13
13
Building Science Corporation -) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 17 Hours of potential winter time air leakage condensation
13
) 1313amp$13
amp 13amp 13)
amp13amp$13
131313
13
1313
13
1313
Building Science Corporation (amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 18 Wall Comparison Chart
$$ 13$$13
$13
amp$
amp$13
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(
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13
$ 13 amp amp
13 13 amp
$13$1313$ 13$
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$ $13$ amp13 $13
13
13 $amp13
13$13 13
$ $ 13amp
amp
Building Science Corporation +) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313
13
13 1313
13
131313 1313
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
E Works Cited
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9$$-+amp+ amp913ampamp 0CAAH9
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0BJJF9
- amp79FA9amp($+(($amp amp+-$13+amp1$$9( amp7BJGE9
+amp17 amp7- 7 $$( $+7amp1213 -amp9 $$amp$
amp$-+8$amp+amp-ampampamp$$ $ampampamp
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=++13 G7CAAJgt9
279amp+- -ampamp2-$ -+ $amp + -amp$amp+
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-++-7139979139amp713997137amp13913913ampampamp913267113$amp5113)
- ampamp amp07amp8amp$+ -amp$amp7CAAI9
3713999amp4(13)( ) $ amp amp
+ amp07amp8amp$+ -amp$amp7CAAG9
(+amp7$$7ampampampamp$9 1+$(+amp13+-$amp+9amp
7DBDCE913+amp7 8+-+17BJJJ9
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$7amp amp7amp amp-913amp )amp amp(amp0$7amp8
$amp$-amp+ amp97CAAG9
-7 amp7amp-amp9( ( amp(amp0+8-$ampamp++7
CAAF9
Building Science Corporation GF wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
Figure 41 ICF wall construction
171 Thermal Control
1313
1313 1313
131313 (
+$)$13 13($
amp)$)
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 42 Nine inch foam ICF with five inches of EPS
Figure 43 Fifteen inch foam ICF with five inches of EPS
13 13 1313
13 1313131313$13$1313
1313amp1313 13 1313
13131313$amp
172 Moisture Control
1313131313131313 13$amp131313
131313 13amp13
$ 13$1313$13ampamp
13 1313$1313131313
131313amp13
1313131313 13amp
173 Constructability and Cost
13131313 $1313$13$ 13
13 13$1313amp13$13
1313 amp13 13
13 13 1313$
13$13 13$131313
131313 1313 13$amp
174 Other Considerations
13 1313 131313$
13$$131313 1313 13
13amp131313$ 131313
1313 13amp13 131313
Building Science Corporation () wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 1313 13131313 1313 13 13
13 13 1313 13
131313 13131313131313
131313 1313 13 13 1313 13
131313131313 131313
13131313
18 Case 8 Advanced framing with spray foam
13 13 13131313131313
13131313131313 13$
13 $
Figure 44 2x6 wall construction with spray foam insulation
181 Thermal Control
13131313 1313131313 13131313131313
131313131313
Building Science Corporation amp( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13amp13 1313$
13amp
0$+ $0
13$
$131313
13131313$1313
13-
Figure 45 Therm modeling of spray foam wall and rim joist
13 amp amp+1+
$+ amp
13-amp(1+)13
amp 131
amp
Table 11 Therm results of spray foam insulation analysis
182 Moisture Control
13 $
1313 13
131313
13
Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313 13 13
13 13 $ 13
131313 23
(+-)$
13 13
1313
13 (+)$
1313 13
1313 3
1313$
1313 13 13
13 1313$
(+) 13 13 1313+-
113 13 13 13
-1313+-$
183 Constructability and Cost
13 13 13 13
$13 13
1313 13 13$
184 Other Considerations
1313
$ 1313
13 1313$
19 Case 9 Hybrid Wall Insulation ndash Flash and Fill
13 $1313
1313 $13
131313$13 131313
13 13$
1313 13 0amp $
13 13
13$ 1313
13 $
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 46 Hybrid wall construction with 2 spray foam and fibrous fill
191 Thermal Control
131313131313
13 1313 13
$amp $ amp 13
131313$(
13 13 13 13
1313
Building Science Corporation amp$ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 47 Therm analysis of hybrid wall system
Table 12 Calculated R-value for a hybrid wall system
192 Moisture Control
+ amp 13
$1313
13 $1313 $ 13
13
13 +(
131313
131313)13(
193 Constructability and Cost
13131313131313
13
1313
194 Other Considerations
1313
1313 1313
1313
Building Science Corporation -+ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 13
13
110 Case 10 Double Stud Wall with Spray Foam
amp 13 13
) 13 13
)13
amp 13 13
131313
13
13 131313
1313 13 1313 13
13
Figure 48 Double stud wall with 2 of spray foam and cellulose fill
1101 Thermal Control
$) 13
13(amp() $
13$
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 49 Therm analysis of double stud wall construction with spray foam
Table 13 Calculated whole wall R-value for a double stud wall system with 2rdquo spray foam
1102 Moisture Control
13 13 (13
13 13
13 1313 13
13 13
($$13(amp$$$13
13 1313 1313 13 13
13 13 13 $13 13
1313 amp+ 13
1313 amp1313 13
13 1313 amp
1313 13 13
1103 Constructability and Cost
13131313 13 13
13131313131313
Building Science Corporation )( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1104 Other Considerations
13 13 13 1313
131313(13 131313 1313 13 amp
13 13 (
131313 1313 13 13 13 13
13 (
111 Case 11 Offset Frame Wall with Exterior Spray Foam
131313 1313 13 1313
13 13 13 13( 13 1313131313 131313
13 1313$ 13 13 13(
13 13 13 13 13 13
$ 13 ( 1313 13 131313131313
1313 13 13( 1313
13 13 13(
13 13 13 13 13(
1313 ( 1313 13 13
1313 (1313 13 13 13 1313
1313 13 13( 1313
13 13 13$13 -++13 13
131313 1313 1313(13 13
13 13 13 )13
13 13 13 13 13 13 13 13
(
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 50 Offset frame wall construction with exterior spray foam
1111 Thermal Control
131313 13 1313131313
1313 131313
13 13 13131313
13 13 13 13 13 13 13
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 51 Therm analysis of an offset truss wall with exterior spray foam
Table 14 Calculated whole wall R-value for an offset framed wall with exterior spray foam
1112 Moisture Control
13
$ 13$
+amp13
+amp$
13 131313
1313 ()amp$13
13 13131313
1313$
1313
13
(-amp$
1113 Constructability and Cost
13 $13
1313 13 13 $
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($( $$
$ $($$($$+
1114 Other Considerations
$$amp$(amp$+
( $ $(($$
ampamp$amp$+
amp$+13 $-
$$(($
112 Case 12 Exterior Insulation Finish System (EIFS)
$(- 13()+
$ $
amp$$+amp$
-016532443405amp(+
13$$$$+
(amp $
$amp(amp$(+
$$ampamp 13$ampamp$(
$amp(+($$
amp$$$ $()+
($amp$13$$
($$ 13($$+
Building Science Corporation 25 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 52 Wall construction using the EIFS cladding system
1121 Thermal Control
1313 1313
1313 1313
1313 131313
13 13 $
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 53 Thermal analysis of an EIFS wall system
Table 15 Calculated whole wall R-value for a EIFS wall system with 4rdquo of EPS
1122 Moisture Control
1313131313131313
131313amp1313
13131313
131313amp
13131313131313
13 13 13+ 13amp 131313
1313131313 131313) amp
1123 Constructability and Cost
131313131313
131313amp1313131313amp
131313131313 1313 13
1313amp
1124 Other Considerations
131313131313amp 13
13131313 131313
13amp13$1313131313
1313131313amp 131313131313
131313131313amp
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
D Conclusions
amp 1313
)- 13$13
13131313 1313
1313
Table 16 Summary of all calculated R-values
131313 amp
amp(
13amp 1313
13 ampamp(1313$
13amp) amp
amp13$ 13$
131313 amp )
( 131313$1313$13
amp+( 1313
13$1313$13
amp 13131313
1313131313 13
131313
13 $
) 13
131313$
$13
13
Building Science Corporation -) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 17 Hours of potential winter time air leakage condensation
13
) 1313amp$13
amp 13amp 13)
amp13amp$13
131313
13
1313
13
1313
Building Science Corporation (amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 18 Wall Comparison Chart
$$ 13$$13
$13
amp$
amp$13
1313
(
1313
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$( $ (
13
$ 13 amp amp
13 13 amp
$13$1313$ 13$
amp
$ $13$ amp13 $13
13
13 $amp13
13$13 13
$ $ 13amp
amp
Building Science Corporation +) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313
13
13 1313
13
131313 1313
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
E Works Cited
9ADF8+amp+ 81$$=-amp-7gt9( amp00CAAI9
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(amp77amp - 9 2ampamp++
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9$$-+amp+ amp913ampamp 0CAAH9
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+amp77amp +amp19+amp$()-$$amp$900 ) $
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- amp79FA9amp($+(($amp amp+-$13+amp1$$9( amp7BJGE9
+amp17 amp7- 7 $$( $+7amp1213 -amp9 $$amp$
amp$-+8$amp+amp-ampampamp$$ $ampampamp
$$$+9( amp07CAAH9
+-79((0131D7CAAH9 (8ltlt91--9lt M D(A5-M ampamp$(
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279amp+- -ampamp2-$ -+ $amp + -amp$amp+
$2amp9 (((ampampampamp7-( 1+CJ=CAAHgt8DBBDBC9
-++-7139979139amp713997137amp13913913ampampamp913267113$amp5113)
- ampamp amp07amp8amp$+ -amp$amp7CAAI9
3713999amp4(13)( ) $ amp amp
+ amp07amp8amp$+ -amp$amp7CAAG9
(+amp7$$7ampampampamp$9 1+$(+amp13+-$amp+9amp
7DBDCE913+amp7 8+-+17BJJJ9
9(amp -amp-7$+++-9(( amp( ampamp0-1CAAC9
(8ltlt9+(+9ltampamplt amp$ltamp09 MBGB=++ADBA7CAAJgt9
$7amp amp7amp amp-913amp )amp amp(amp0$7amp8
$amp$-amp+ amp97CAAG9
-7 amp7amp-amp9( ( amp(amp0+8-$ampamp++7
CAAF9
Building Science Corporation GF wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
Figure 42 Nine inch foam ICF with five inches of EPS
Figure 43 Fifteen inch foam ICF with five inches of EPS
13 13 1313
13 1313131313$13$1313
1313amp1313 13 1313
13131313$amp
172 Moisture Control
1313131313131313 13$amp131313
131313 13amp13
$ 13$1313$13ampamp
13 1313$1313131313
131313amp13
1313131313 13amp
173 Constructability and Cost
13131313 $1313$13$ 13
13 13$1313amp13$13
1313 amp13 13
13 13 1313$
13$13 13$131313
131313 1313 13$amp
174 Other Considerations
13 1313 131313$
13$$131313 1313 13
13amp131313$ 131313
1313 13amp13 131313
Building Science Corporation () wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 1313 13131313 1313 13 13
13 13 1313 13
131313 13131313131313
131313 1313 13 13 1313 13
131313131313 131313
13131313
18 Case 8 Advanced framing with spray foam
13 13 13131313131313
13131313131313 13$
13 $
Figure 44 2x6 wall construction with spray foam insulation
181 Thermal Control
13131313 1313131313 13131313131313
131313131313
Building Science Corporation amp( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13amp13 1313$
13amp
0$+ $0
13$
$131313
13131313$1313
13-
Figure 45 Therm modeling of spray foam wall and rim joist
13 amp amp+1+
$+ amp
13-amp(1+)13
amp 131
amp
Table 11 Therm results of spray foam insulation analysis
182 Moisture Control
13 $
1313 13
131313
13
Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313 13 13
13 13 $ 13
131313 23
(+-)$
13 13
1313
13 (+)$
1313 13
1313 3
1313$
1313 13 13
13 1313$
(+) 13 13 1313+-
113 13 13 13
-1313+-$
183 Constructability and Cost
13 13 13 13
$13 13
1313 13 13$
184 Other Considerations
1313
$ 1313
13 1313$
19 Case 9 Hybrid Wall Insulation ndash Flash and Fill
13 $1313
1313 $13
131313$13 131313
13 13$
1313 13 0amp $
13 13
13$ 1313
13 $
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 46 Hybrid wall construction with 2 spray foam and fibrous fill
191 Thermal Control
131313131313
13 1313 13
$amp $ amp 13
131313$(
13 13 13 13
1313
Building Science Corporation amp$ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 47 Therm analysis of hybrid wall system
Table 12 Calculated R-value for a hybrid wall system
192 Moisture Control
+ amp 13
$1313
13 $1313 $ 13
13
13 +(
131313
131313)13(
193 Constructability and Cost
13131313131313
13
1313
194 Other Considerations
1313
1313 1313
1313
Building Science Corporation -+ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 13
13
110 Case 10 Double Stud Wall with Spray Foam
amp 13 13
) 13 13
)13
amp 13 13
131313
13
13 131313
1313 13 1313 13
13
Figure 48 Double stud wall with 2 of spray foam and cellulose fill
1101 Thermal Control
$) 13
13(amp() $
13$
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 49 Therm analysis of double stud wall construction with spray foam
Table 13 Calculated whole wall R-value for a double stud wall system with 2rdquo spray foam
1102 Moisture Control
13 13 (13
13 13
13 1313 13
13 13
($$13(amp$$$13
13 1313 1313 13 13
13 13 13 $13 13
1313 amp+ 13
1313 amp1313 13
13 1313 amp
1313 13 13
1103 Constructability and Cost
13131313 13 13
13131313131313
Building Science Corporation )( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1104 Other Considerations
13 13 13 1313
131313(13 131313 1313 13 amp
13 13 (
131313 1313 13 13 13 13
13 (
111 Case 11 Offset Frame Wall with Exterior Spray Foam
131313 1313 13 1313
13 13 13 13( 13 1313131313 131313
13 1313$ 13 13 13(
13 13 13 13 13 13
$ 13 ( 1313 13 131313131313
1313 13 13( 1313
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13 13 13 13 13(
1313 ( 1313 13 13
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131313 1313 1313(13 13
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13 13 13 13 13 13 13 13
(
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 50 Offset frame wall construction with exterior spray foam
1111 Thermal Control
131313 13 1313131313
1313 131313
13 13 13131313
13 13 13 13 13 13 13
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 51 Therm analysis of an offset truss wall with exterior spray foam
Table 14 Calculated whole wall R-value for an offset framed wall with exterior spray foam
1112 Moisture Control
13
$ 13$
+amp13
+amp$
13 131313
1313 ()amp$13
13 13131313
1313$
1313
13
(-amp$
1113 Constructability and Cost
13 $13
1313 13 13 $
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($( $$
$ $($$($$+
1114 Other Considerations
$$amp$(amp$+
( $ $(($$
ampamp$amp$+
amp$+13 $-
$$(($
112 Case 12 Exterior Insulation Finish System (EIFS)
$(- 13()+
$ $
amp$$+amp$
-016532443405amp(+
13$$$$+
(amp $
$amp(amp$(+
$$ampamp 13$ampamp$(
$amp(+($$
amp$$$ $()+
($amp$13$$
($$ 13($$+
Building Science Corporation 25 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 52 Wall construction using the EIFS cladding system
1121 Thermal Control
1313 1313
1313 1313
1313 131313
13 13 $
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 53 Thermal analysis of an EIFS wall system
Table 15 Calculated whole wall R-value for a EIFS wall system with 4rdquo of EPS
1122 Moisture Control
1313131313131313
131313amp1313
13131313
131313amp
13131313131313
13 13 13+ 13amp 131313
1313131313 131313) amp
1123 Constructability and Cost
131313131313
131313amp1313131313amp
131313131313 1313 13
1313amp
1124 Other Considerations
131313131313amp 13
13131313 131313
13amp13$1313131313
1313131313amp 131313131313
131313131313amp
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
D Conclusions
amp 1313
)- 13$13
13131313 1313
1313
Table 16 Summary of all calculated R-values
131313 amp
amp(
13amp 1313
13 ampamp(1313$
13amp) amp
amp13$ 13$
131313 amp )
( 131313$1313$13
amp+( 1313
13$1313$13
amp 13131313
1313131313 13
131313
13 $
) 13
131313$
$13
13
Building Science Corporation -) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 17 Hours of potential winter time air leakage condensation
13
) 1313amp$13
amp 13amp 13)
amp13amp$13
131313
13
1313
13
1313
Building Science Corporation (amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 18 Wall Comparison Chart
$$ 13$$13
$13
amp$
amp$13
1313
(
1313
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$( $ (
13
$ 13 amp amp
13 13 amp
$13$1313$ 13$
amp
$ $13$ amp13 $13
13
13 $amp13
13$13 13
$ $ 13amp
amp
Building Science Corporation +) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313
13
13 1313
13
131313 1313
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
E Works Cited
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+amp$-$amp+913ampamp)327307CAAD9
9$$-+amp+ amp913ampamp 0CAAH9
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+amp77amp +amp19+amp$()-$$amp$900 ) $
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-++-7139979139amp713997137amp13913913ampampamp913267113$amp5113)
- ampamp amp07amp8amp$+ -amp$amp7CAAI9
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+ amp07amp8amp$+ -amp$amp7CAAG9
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CAAF9
Building Science Corporation GF wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
13 1313 13131313 1313 13 13
13 13 1313 13
131313 13131313131313
131313 1313 13 13 1313 13
131313131313 131313
13131313
18 Case 8 Advanced framing with spray foam
13 13 13131313131313
13131313131313 13$
13 $
Figure 44 2x6 wall construction with spray foam insulation
181 Thermal Control
13131313 1313131313 13131313131313
131313131313
Building Science Corporation amp( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13amp13 1313$
13amp
0$+ $0
13$
$131313
13131313$1313
13-
Figure 45 Therm modeling of spray foam wall and rim joist
13 amp amp+1+
$+ amp
13-amp(1+)13
amp 131
amp
Table 11 Therm results of spray foam insulation analysis
182 Moisture Control
13 $
1313 13
131313
13
Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313 13 13
13 13 $ 13
131313 23
(+-)$
13 13
1313
13 (+)$
1313 13
1313 3
1313$
1313 13 13
13 1313$
(+) 13 13 1313+-
113 13 13 13
-1313+-$
183 Constructability and Cost
13 13 13 13
$13 13
1313 13 13$
184 Other Considerations
1313
$ 1313
13 1313$
19 Case 9 Hybrid Wall Insulation ndash Flash and Fill
13 $1313
1313 $13
131313$13 131313
13 13$
1313 13 0amp $
13 13
13$ 1313
13 $
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 46 Hybrid wall construction with 2 spray foam and fibrous fill
191 Thermal Control
131313131313
13 1313 13
$amp $ amp 13
131313$(
13 13 13 13
1313
Building Science Corporation amp$ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 47 Therm analysis of hybrid wall system
Table 12 Calculated R-value for a hybrid wall system
192 Moisture Control
+ amp 13
$1313
13 $1313 $ 13
13
13 +(
131313
131313)13(
193 Constructability and Cost
13131313131313
13
1313
194 Other Considerations
1313
1313 1313
1313
Building Science Corporation -+ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 13
13
110 Case 10 Double Stud Wall with Spray Foam
amp 13 13
) 13 13
)13
amp 13 13
131313
13
13 131313
1313 13 1313 13
13
Figure 48 Double stud wall with 2 of spray foam and cellulose fill
1101 Thermal Control
$) 13
13(amp() $
13$
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 49 Therm analysis of double stud wall construction with spray foam
Table 13 Calculated whole wall R-value for a double stud wall system with 2rdquo spray foam
1102 Moisture Control
13 13 (13
13 13
13 1313 13
13 13
($$13(amp$$$13
13 1313 1313 13 13
13 13 13 $13 13
1313 amp+ 13
1313 amp1313 13
13 1313 amp
1313 13 13
1103 Constructability and Cost
13131313 13 13
13131313131313
Building Science Corporation )( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1104 Other Considerations
13 13 13 1313
131313(13 131313 1313 13 amp
13 13 (
131313 1313 13 13 13 13
13 (
111 Case 11 Offset Frame Wall with Exterior Spray Foam
131313 1313 13 1313
13 13 13 13( 13 1313131313 131313
13 1313$ 13 13 13(
13 13 13 13 13 13
$ 13 ( 1313 13 131313131313
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13 13 13(
13 13 13 13 13(
1313 ( 1313 13 13
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13 13 13$13 -++13 13
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13 13 13 )13
13 13 13 13 13 13 13 13
(
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 50 Offset frame wall construction with exterior spray foam
1111 Thermal Control
131313 13 1313131313
1313 131313
13 13 13131313
13 13 13 13 13 13 13
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 51 Therm analysis of an offset truss wall with exterior spray foam
Table 14 Calculated whole wall R-value for an offset framed wall with exterior spray foam
1112 Moisture Control
13
$ 13$
+amp13
+amp$
13 131313
1313 ()amp$13
13 13131313
1313$
1313
13
(-amp$
1113 Constructability and Cost
13 $13
1313 13 13 $
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($( $$
$ $($$($$+
1114 Other Considerations
$$amp$(amp$+
( $ $(($$
ampamp$amp$+
amp$+13 $-
$$(($
112 Case 12 Exterior Insulation Finish System (EIFS)
$(- 13()+
$ $
amp$$+amp$
-016532443405amp(+
13$$$$+
(amp $
$amp(amp$(+
$$ampamp 13$ampamp$(
$amp(+($$
amp$$$ $()+
($amp$13$$
($$ 13($$+
Building Science Corporation 25 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 52 Wall construction using the EIFS cladding system
1121 Thermal Control
1313 1313
1313 1313
1313 131313
13 13 $
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 53 Thermal analysis of an EIFS wall system
Table 15 Calculated whole wall R-value for a EIFS wall system with 4rdquo of EPS
1122 Moisture Control
1313131313131313
131313amp1313
13131313
131313amp
13131313131313
13 13 13+ 13amp 131313
1313131313 131313) amp
1123 Constructability and Cost
131313131313
131313amp1313131313amp
131313131313 1313 13
1313amp
1124 Other Considerations
131313131313amp 13
13131313 131313
13amp13$1313131313
1313131313amp 131313131313
131313131313amp
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
D Conclusions
amp 1313
)- 13$13
13131313 1313
1313
Table 16 Summary of all calculated R-values
131313 amp
amp(
13amp 1313
13 ampamp(1313$
13amp) amp
amp13$ 13$
131313 amp )
( 131313$1313$13
amp+( 1313
13$1313$13
amp 13131313
1313131313 13
131313
13 $
) 13
131313$
$13
13
Building Science Corporation -) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 17 Hours of potential winter time air leakage condensation
13
) 1313amp$13
amp 13amp 13)
amp13amp$13
131313
13
1313
13
1313
Building Science Corporation (amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 18 Wall Comparison Chart
$$ 13$$13
$13
amp$
amp$13
1313
(
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13 13 amp
$13$1313$ 13$
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$ $13$ amp13 $13
13
13 $amp13
13$13 13
$ $ 13amp
amp
Building Science Corporation +) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313
13
13 1313
13
131313 1313
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
E Works Cited
9ADF8+amp+ 81$$=-amp-7gt9( amp00CAAI9
(8ltlt9-$amp+amp9lt-amp+lt(+lt+(ADF+amp+ 1$$
-amp-lt+ampC +1$$ -+lt+ M KCA -+9
(amp77amp - 9 2ampamp++
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9$$-+amp+ amp913ampamp 0CAAH9
(8ltlt9 9lt+ LL+ampL$19+(09
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- amp79FA9amp($+(($amp amp+-$13+amp1$$9( amp7BJGE9
+amp17 amp7- 7 $$( $+7amp1213 -amp9 $$amp$
amp$-+8$amp+amp-ampampamp$$ $ampampamp
$$$+9( amp07CAAH9
+-79((0131D7CAAH9 (8ltlt91--9lt M D(A5-M ampamp$(
=++13 G7CAAJgt9
279amp+- -ampamp2-$ -+ $amp + -amp$amp+
$2amp9 (((ampampampamp7-( 1+CJ=CAAHgt8DBBDBC9
-++-7139979139amp713997137amp13913913ampampamp913267113$amp5113)
- ampamp amp07amp8amp$+ -amp$amp7CAAI9
3713999amp4(13)( ) $ amp amp
+ amp07amp8amp$+ -amp$amp7CAAG9
(+amp7$$7ampampampamp$9 1+$(+amp13+-$amp+9amp
7DBDCE913+amp7 8+-+17BJJJ9
9(amp -amp-7$+++-9(( amp( ampamp0-1CAAC9
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$7amp amp7amp amp-913amp )amp amp(amp0$7amp8
$amp$-amp+ amp97CAAG9
-7 amp7amp-amp9( ( amp(amp0+8-$ampamp++7
CAAF9
Building Science Corporation GF wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
13amp13 1313$
13amp
0$+ $0
13$
$131313
13131313$1313
13-
Figure 45 Therm modeling of spray foam wall and rim joist
13 amp amp+1+
$+ amp
13-amp(1+)13
amp 131
amp
Table 11 Therm results of spray foam insulation analysis
182 Moisture Control
13 $
1313 13
131313
13
Building Science Corporation -1 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313 13 13
13 13 $ 13
131313 23
(+-)$
13 13
1313
13 (+)$
1313 13
1313 3
1313$
1313 13 13
13 1313$
(+) 13 13 1313+-
113 13 13 13
-1313+-$
183 Constructability and Cost
13 13 13 13
$13 13
1313 13 13$
184 Other Considerations
1313
$ 1313
13 1313$
19 Case 9 Hybrid Wall Insulation ndash Flash and Fill
13 $1313
1313 $13
131313$13 131313
13 13$
1313 13 0amp $
13 13
13$ 1313
13 $
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 46 Hybrid wall construction with 2 spray foam and fibrous fill
191 Thermal Control
131313131313
13 1313 13
$amp $ amp 13
131313$(
13 13 13 13
1313
Building Science Corporation amp$ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 47 Therm analysis of hybrid wall system
Table 12 Calculated R-value for a hybrid wall system
192 Moisture Control
+ amp 13
$1313
13 $1313 $ 13
13
13 +(
131313
131313)13(
193 Constructability and Cost
13131313131313
13
1313
194 Other Considerations
1313
1313 1313
1313
Building Science Corporation -+ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 13
13
110 Case 10 Double Stud Wall with Spray Foam
amp 13 13
) 13 13
)13
amp 13 13
131313
13
13 131313
1313 13 1313 13
13
Figure 48 Double stud wall with 2 of spray foam and cellulose fill
1101 Thermal Control
$) 13
13(amp() $
13$
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 49 Therm analysis of double stud wall construction with spray foam
Table 13 Calculated whole wall R-value for a double stud wall system with 2rdquo spray foam
1102 Moisture Control
13 13 (13
13 13
13 1313 13
13 13
($$13(amp$$$13
13 1313 1313 13 13
13 13 13 $13 13
1313 amp+ 13
1313 amp1313 13
13 1313 amp
1313 13 13
1103 Constructability and Cost
13131313 13 13
13131313131313
Building Science Corporation )( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1104 Other Considerations
13 13 13 1313
131313(13 131313 1313 13 amp
13 13 (
131313 1313 13 13 13 13
13 (
111 Case 11 Offset Frame Wall with Exterior Spray Foam
131313 1313 13 1313
13 13 13 13( 13 1313131313 131313
13 1313$ 13 13 13(
13 13 13 13 13 13
$ 13 ( 1313 13 131313131313
1313 13 13( 1313
13 13 13(
13 13 13 13 13(
1313 ( 1313 13 13
1313 (1313 13 13 13 1313
1313 13 13( 1313
13 13 13$13 -++13 13
131313 1313 1313(13 13
13 13 13 )13
13 13 13 13 13 13 13 13
(
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 50 Offset frame wall construction with exterior spray foam
1111 Thermal Control
131313 13 1313131313
1313 131313
13 13 13131313
13 13 13 13 13 13 13
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 51 Therm analysis of an offset truss wall with exterior spray foam
Table 14 Calculated whole wall R-value for an offset framed wall with exterior spray foam
1112 Moisture Control
13
$ 13$
+amp13
+amp$
13 131313
1313 ()amp$13
13 13131313
1313$
1313
13
(-amp$
1113 Constructability and Cost
13 $13
1313 13 13 $
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($( $$
$ $($$($$+
1114 Other Considerations
$$amp$(amp$+
( $ $(($$
ampamp$amp$+
amp$+13 $-
$$(($
112 Case 12 Exterior Insulation Finish System (EIFS)
$(- 13()+
$ $
amp$$+amp$
-016532443405amp(+
13$$$$+
(amp $
$amp(amp$(+
$$ampamp 13$ampamp$(
$amp(+($$
amp$$$ $()+
($amp$13$$
($$ 13($$+
Building Science Corporation 25 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 52 Wall construction using the EIFS cladding system
1121 Thermal Control
1313 1313
1313 1313
1313 131313
13 13 $
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 53 Thermal analysis of an EIFS wall system
Table 15 Calculated whole wall R-value for a EIFS wall system with 4rdquo of EPS
1122 Moisture Control
1313131313131313
131313amp1313
13131313
131313amp
13131313131313
13 13 13+ 13amp 131313
1313131313 131313) amp
1123 Constructability and Cost
131313131313
131313amp1313131313amp
131313131313 1313 13
1313amp
1124 Other Considerations
131313131313amp 13
13131313 131313
13amp13$1313131313
1313131313amp 131313131313
131313131313amp
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
D Conclusions
amp 1313
)- 13$13
13131313 1313
1313
Table 16 Summary of all calculated R-values
131313 amp
amp(
13amp 1313
13 ampamp(1313$
13amp) amp
amp13$ 13$
131313 amp )
( 131313$1313$13
amp+( 1313
13$1313$13
amp 13131313
1313131313 13
131313
13 $
) 13
131313$
$13
13
Building Science Corporation -) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 17 Hours of potential winter time air leakage condensation
13
) 1313amp$13
amp 13amp 13)
amp13amp$13
131313
13
1313
13
1313
Building Science Corporation (amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 18 Wall Comparison Chart
$$ 13$$13
$13
amp$
amp$13
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(
1313
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$( $ (
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$ 13 amp amp
13 13 amp
$13$1313$ 13$
amp
$ $13$ amp13 $13
13
13 $amp13
13$13 13
$ $ 13amp
amp
Building Science Corporation +) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313
13
13 1313
13
131313 1313
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
E Works Cited
9ADF8+amp+ 81$$=-amp-7gt9( amp00CAAI9
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(amp77amp - 9 2ampamp++
+amp$-$amp+913ampamp)327307CAAD9
9$$-+amp+ amp913ampamp 0CAAH9
(8ltlt9 9lt+ LL+ampL$19+(09
+amp77amp +amp19+amp$()-$$amp$900 ) $
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- amp79FA9amp($+(($amp amp+-$13+amp1$$9( amp7BJGE9
+amp17 amp7- 7 $$( $+7amp1213 -amp9 $$amp$
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=++13 G7CAAJgt9
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-++-7139979139amp713997137amp13913913ampampamp913267113$amp5113)
- ampamp amp07amp8amp$+ -amp$amp7CAAI9
3713999amp4(13)( ) $ amp amp
+ amp07amp8amp$+ -amp$amp7CAAG9
(+amp7$$7ampampampamp$9 1+$(+amp13+-$amp+9amp
7DBDCE913+amp7 8+-+17BJJJ9
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(8ltlt9+(+9ltampamplt amp$ltamp09 MBGB=++ADBA7CAAJgt9
$7amp amp7amp amp-913amp )amp amp(amp0$7amp8
$amp$-amp+ amp97CAAG9
-7 amp7amp-amp9( ( amp(amp0+8-$ampamp++7
CAAF9
Building Science Corporation GF wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
1313 13 13
13 13 $ 13
131313 23
(+-)$
13 13
1313
13 (+)$
1313 13
1313 3
1313$
1313 13 13
13 1313$
(+) 13 13 1313+-
113 13 13 13
-1313+-$
183 Constructability and Cost
13 13 13 13
$13 13
1313 13 13$
184 Other Considerations
1313
$ 1313
13 1313$
19 Case 9 Hybrid Wall Insulation ndash Flash and Fill
13 $1313
1313 $13
131313$13 131313
13 13$
1313 13 0amp $
13 13
13$ 1313
13 $
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 46 Hybrid wall construction with 2 spray foam and fibrous fill
191 Thermal Control
131313131313
13 1313 13
$amp $ amp 13
131313$(
13 13 13 13
1313
Building Science Corporation amp$ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 47 Therm analysis of hybrid wall system
Table 12 Calculated R-value for a hybrid wall system
192 Moisture Control
+ amp 13
$1313
13 $1313 $ 13
13
13 +(
131313
131313)13(
193 Constructability and Cost
13131313131313
13
1313
194 Other Considerations
1313
1313 1313
1313
Building Science Corporation -+ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 13
13
110 Case 10 Double Stud Wall with Spray Foam
amp 13 13
) 13 13
)13
amp 13 13
131313
13
13 131313
1313 13 1313 13
13
Figure 48 Double stud wall with 2 of spray foam and cellulose fill
1101 Thermal Control
$) 13
13(amp() $
13$
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 49 Therm analysis of double stud wall construction with spray foam
Table 13 Calculated whole wall R-value for a double stud wall system with 2rdquo spray foam
1102 Moisture Control
13 13 (13
13 13
13 1313 13
13 13
($$13(amp$$$13
13 1313 1313 13 13
13 13 13 $13 13
1313 amp+ 13
1313 amp1313 13
13 1313 amp
1313 13 13
1103 Constructability and Cost
13131313 13 13
13131313131313
Building Science Corporation )( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1104 Other Considerations
13 13 13 1313
131313(13 131313 1313 13 amp
13 13 (
131313 1313 13 13 13 13
13 (
111 Case 11 Offset Frame Wall with Exterior Spray Foam
131313 1313 13 1313
13 13 13 13( 13 1313131313 131313
13 1313$ 13 13 13(
13 13 13 13 13 13
$ 13 ( 1313 13 131313131313
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1313 ( 1313 13 13
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13 13 13 13 13 13 13 13
(
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 50 Offset frame wall construction with exterior spray foam
1111 Thermal Control
131313 13 1313131313
1313 131313
13 13 13131313
13 13 13 13 13 13 13
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 51 Therm analysis of an offset truss wall with exterior spray foam
Table 14 Calculated whole wall R-value for an offset framed wall with exterior spray foam
1112 Moisture Control
13
$ 13$
+amp13
+amp$
13 131313
1313 ()amp$13
13 13131313
1313$
1313
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(-amp$
1113 Constructability and Cost
13 $13
1313 13 13 $
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($( $$
$ $($$($$+
1114 Other Considerations
$$amp$(amp$+
( $ $(($$
ampamp$amp$+
amp$+13 $-
$$(($
112 Case 12 Exterior Insulation Finish System (EIFS)
$(- 13()+
$ $
amp$$+amp$
-016532443405amp(+
13$$$$+
(amp $
$amp(amp$(+
$$ampamp 13$ampamp$(
$amp(+($$
amp$$$ $()+
($amp$13$$
($$ 13($$+
Building Science Corporation 25 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 52 Wall construction using the EIFS cladding system
1121 Thermal Control
1313 1313
1313 1313
1313 131313
13 13 $
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 53 Thermal analysis of an EIFS wall system
Table 15 Calculated whole wall R-value for a EIFS wall system with 4rdquo of EPS
1122 Moisture Control
1313131313131313
131313amp1313
13131313
131313amp
13131313131313
13 13 13+ 13amp 131313
1313131313 131313) amp
1123 Constructability and Cost
131313131313
131313amp1313131313amp
131313131313 1313 13
1313amp
1124 Other Considerations
131313131313amp 13
13131313 131313
13amp13$1313131313
1313131313amp 131313131313
131313131313amp
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
D Conclusions
amp 1313
)- 13$13
13131313 1313
1313
Table 16 Summary of all calculated R-values
131313 amp
amp(
13amp 1313
13 ampamp(1313$
13amp) amp
amp13$ 13$
131313 amp )
( 131313$1313$13
amp+( 1313
13$1313$13
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1313131313 13
131313
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) 13
131313$
$13
13
Building Science Corporation -) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 17 Hours of potential winter time air leakage condensation
13
) 1313amp$13
amp 13amp 13)
amp13amp$13
131313
13
1313
13
1313
Building Science Corporation (amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 18 Wall Comparison Chart
$$ 13$$13
$13
amp$
amp$13
1313
(
1313
$amp ( 13
$( $ (
13
$ 13 amp amp
13 13 amp
$13$1313$ 13$
amp
$ $13$ amp13 $13
13
13 $amp13
13$13 13
$ $ 13amp
amp
Building Science Corporation +) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313
13
13 1313
13
131313 1313
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
E Works Cited
9ADF8+amp+ 81$$=-amp-7gt9( amp00CAAI9
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(amp77amp - 9 2ampamp++
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9$$-+amp+ amp913ampamp 0CAAH9
(8ltlt9 9lt+ LL+ampL$19+(09
+amp77amp +amp19+amp$()-$$amp$900 ) $
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- amp79FA9amp($+(($amp amp+-$13+amp1$$9( amp7BJGE9
+amp17 amp7- 7 $$( $+7amp1213 -amp9 $$amp$
amp$-+8$amp+amp-ampampamp$$ $ampampamp
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+-79((0131D7CAAH9 (8ltlt91--9lt M D(A5-M ampamp$(
=++13 G7CAAJgt9
279amp+- -ampamp2-$ -+ $amp + -amp$amp+
$2amp9 (((ampampampamp7-( 1+CJ=CAAHgt8DBBDBC9
-++-7139979139amp713997137amp13913913ampampamp913267113$amp5113)
- ampamp amp07amp8amp$+ -amp$amp7CAAI9
3713999amp4(13)( ) $ amp amp
+ amp07amp8amp$+ -amp$amp7CAAG9
(+amp7$$7ampampampamp$9 1+$(+amp13+-$amp+9amp
7DBDCE913+amp7 8+-+17BJJJ9
9(amp -amp-7$+++-9(( amp( ampamp0-1CAAC9
(8ltlt9+(+9ltampamplt amp$ltamp09 MBGB=++ADBA7CAAJgt9
$7amp amp7amp amp-913amp )amp amp(amp0$7amp8
$amp$-amp+ amp97CAAG9
-7 amp7amp-amp9( ( amp(amp0+8-$ampamp++7
CAAF9
Building Science Corporation GF wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
Figure 46 Hybrid wall construction with 2 spray foam and fibrous fill
191 Thermal Control
131313131313
13 1313 13
$amp $ amp 13
131313$(
13 13 13 13
1313
Building Science Corporation amp$ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 47 Therm analysis of hybrid wall system
Table 12 Calculated R-value for a hybrid wall system
192 Moisture Control
+ amp 13
$1313
13 $1313 $ 13
13
13 +(
131313
131313)13(
193 Constructability and Cost
13131313131313
13
1313
194 Other Considerations
1313
1313 1313
1313
Building Science Corporation -+ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 13
13
110 Case 10 Double Stud Wall with Spray Foam
amp 13 13
) 13 13
)13
amp 13 13
131313
13
13 131313
1313 13 1313 13
13
Figure 48 Double stud wall with 2 of spray foam and cellulose fill
1101 Thermal Control
$) 13
13(amp() $
13$
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 49 Therm analysis of double stud wall construction with spray foam
Table 13 Calculated whole wall R-value for a double stud wall system with 2rdquo spray foam
1102 Moisture Control
13 13 (13
13 13
13 1313 13
13 13
($$13(amp$$$13
13 1313 1313 13 13
13 13 13 $13 13
1313 amp+ 13
1313 amp1313 13
13 1313 amp
1313 13 13
1103 Constructability and Cost
13131313 13 13
13131313131313
Building Science Corporation )( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1104 Other Considerations
13 13 13 1313
131313(13 131313 1313 13 amp
13 13 (
131313 1313 13 13 13 13
13 (
111 Case 11 Offset Frame Wall with Exterior Spray Foam
131313 1313 13 1313
13 13 13 13( 13 1313131313 131313
13 1313$ 13 13 13(
13 13 13 13 13 13
$ 13 ( 1313 13 131313131313
1313 13 13( 1313
13 13 13(
13 13 13 13 13(
1313 ( 1313 13 13
1313 (1313 13 13 13 1313
1313 13 13( 1313
13 13 13$13 -++13 13
131313 1313 1313(13 13
13 13 13 )13
13 13 13 13 13 13 13 13
(
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 50 Offset frame wall construction with exterior spray foam
1111 Thermal Control
131313 13 1313131313
1313 131313
13 13 13131313
13 13 13 13 13 13 13
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 51 Therm analysis of an offset truss wall with exterior spray foam
Table 14 Calculated whole wall R-value for an offset framed wall with exterior spray foam
1112 Moisture Control
13
$ 13$
+amp13
+amp$
13 131313
1313 ()amp$13
13 13131313
1313$
1313
13
(-amp$
1113 Constructability and Cost
13 $13
1313 13 13 $
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($( $$
$ $($$($$+
1114 Other Considerations
$$amp$(amp$+
( $ $(($$
ampamp$amp$+
amp$+13 $-
$$(($
112 Case 12 Exterior Insulation Finish System (EIFS)
$(- 13()+
$ $
amp$$+amp$
-016532443405amp(+
13$$$$+
(amp $
$amp(amp$(+
$$ampamp 13$ampamp$(
$amp(+($$
amp$$$ $()+
($amp$13$$
($$ 13($$+
Building Science Corporation 25 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 52 Wall construction using the EIFS cladding system
1121 Thermal Control
1313 1313
1313 1313
1313 131313
13 13 $
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 53 Thermal analysis of an EIFS wall system
Table 15 Calculated whole wall R-value for a EIFS wall system with 4rdquo of EPS
1122 Moisture Control
1313131313131313
131313amp1313
13131313
131313amp
13131313131313
13 13 13+ 13amp 131313
1313131313 131313) amp
1123 Constructability and Cost
131313131313
131313amp1313131313amp
131313131313 1313 13
1313amp
1124 Other Considerations
131313131313amp 13
13131313 131313
13amp13$1313131313
1313131313amp 131313131313
131313131313amp
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
D Conclusions
amp 1313
)- 13$13
13131313 1313
1313
Table 16 Summary of all calculated R-values
131313 amp
amp(
13amp 1313
13 ampamp(1313$
13amp) amp
amp13$ 13$
131313 amp )
( 131313$1313$13
amp+( 1313
13$1313$13
amp 13131313
1313131313 13
131313
13 $
) 13
131313$
$13
13
Building Science Corporation -) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 17 Hours of potential winter time air leakage condensation
13
) 1313amp$13
amp 13amp 13)
amp13amp$13
131313
13
1313
13
1313
Building Science Corporation (amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 18 Wall Comparison Chart
$$ 13$$13
$13
amp$
amp$13
1313
(
1313
$amp ( 13
$( $ (
13
$ 13 amp amp
13 13 amp
$13$1313$ 13$
amp
$ $13$ amp13 $13
13
13 $amp13
13$13 13
$ $ 13amp
amp
Building Science Corporation +) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313
13
13 1313
13
131313 1313
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
E Works Cited
9ADF8+amp+ 81$$=-amp-7gt9( amp00CAAI9
(8ltlt9-$amp+amp9lt-amp+lt(+lt+(ADF+amp+ 1$$
-amp-lt+ampC +1$$ -+lt+ M KCA -+9
(amp77amp - 9 2ampamp++
+amp$-$amp+913ampamp)327307CAAD9
9$$-+amp+ amp913ampamp 0CAAH9
(8ltlt9 9lt+ LL+ampL$19+(09
+amp77amp +amp19+amp$()-$$amp$900 ) $
0BJJF9
- amp79FA9amp($+(($amp amp+-$13+amp1$$9( amp7BJGE9
+amp17 amp7- 7 $$( $+7amp1213 -amp9 $$amp$
amp$-+8$amp+amp-ampampamp$$ $ampampamp
$$$+9( amp07CAAH9
+-79((0131D7CAAH9 (8ltlt91--9lt M D(A5-M ampamp$(
=++13 G7CAAJgt9
279amp+- -ampamp2-$ -+ $amp + -amp$amp+
$2amp9 (((ampampampamp7-( 1+CJ=CAAHgt8DBBDBC9
-++-7139979139amp713997137amp13913913ampampamp913267113$amp5113)
- ampamp amp07amp8amp$+ -amp$amp7CAAI9
3713999amp4(13)( ) $ amp amp
+ amp07amp8amp$+ -amp$amp7CAAG9
(+amp7$$7ampampampamp$9 1+$(+amp13+-$amp+9amp
7DBDCE913+amp7 8+-+17BJJJ9
9(amp -amp-7$+++-9(( amp( ampamp0-1CAAC9
(8ltlt9+(+9ltampamplt amp$ltamp09 MBGB=++ADBA7CAAJgt9
$7amp amp7amp amp-913amp )amp amp(amp0$7amp8
$amp$-amp+ amp97CAAG9
-7 amp7amp-amp9( ( amp(amp0+8-$ampamp++7
CAAF9
Building Science Corporation GF wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
Figure 47 Therm analysis of hybrid wall system
Table 12 Calculated R-value for a hybrid wall system
192 Moisture Control
+ amp 13
$1313
13 $1313 $ 13
13
13 +(
131313
131313)13(
193 Constructability and Cost
13131313131313
13
1313
194 Other Considerations
1313
1313 1313
1313
Building Science Corporation -+ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
13 13
13
110 Case 10 Double Stud Wall with Spray Foam
amp 13 13
) 13 13
)13
amp 13 13
131313
13
13 131313
1313 13 1313 13
13
Figure 48 Double stud wall with 2 of spray foam and cellulose fill
1101 Thermal Control
$) 13
13(amp() $
13$
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 49 Therm analysis of double stud wall construction with spray foam
Table 13 Calculated whole wall R-value for a double stud wall system with 2rdquo spray foam
1102 Moisture Control
13 13 (13
13 13
13 1313 13
13 13
($$13(amp$$$13
13 1313 1313 13 13
13 13 13 $13 13
1313 amp+ 13
1313 amp1313 13
13 1313 amp
1313 13 13
1103 Constructability and Cost
13131313 13 13
13131313131313
Building Science Corporation )( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1104 Other Considerations
13 13 13 1313
131313(13 131313 1313 13 amp
13 13 (
131313 1313 13 13 13 13
13 (
111 Case 11 Offset Frame Wall with Exterior Spray Foam
131313 1313 13 1313
13 13 13 13( 13 1313131313 131313
13 1313$ 13 13 13(
13 13 13 13 13 13
$ 13 ( 1313 13 131313131313
1313 13 13( 1313
13 13 13(
13 13 13 13 13(
1313 ( 1313 13 13
1313 (1313 13 13 13 1313
1313 13 13( 1313
13 13 13$13 -++13 13
131313 1313 1313(13 13
13 13 13 )13
13 13 13 13 13 13 13 13
(
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 50 Offset frame wall construction with exterior spray foam
1111 Thermal Control
131313 13 1313131313
1313 131313
13 13 13131313
13 13 13 13 13 13 13
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 51 Therm analysis of an offset truss wall with exterior spray foam
Table 14 Calculated whole wall R-value for an offset framed wall with exterior spray foam
1112 Moisture Control
13
$ 13$
+amp13
+amp$
13 131313
1313 ()amp$13
13 13131313
1313$
1313
13
(-amp$
1113 Constructability and Cost
13 $13
1313 13 13 $
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($( $$
$ $($$($$+
1114 Other Considerations
$$amp$(amp$+
( $ $(($$
ampamp$amp$+
amp$+13 $-
$$(($
112 Case 12 Exterior Insulation Finish System (EIFS)
$(- 13()+
$ $
amp$$+amp$
-016532443405amp(+
13$$$$+
(amp $
$amp(amp$(+
$$ampamp 13$ampamp$(
$amp(+($$
amp$$$ $()+
($amp$13$$
($$ 13($$+
Building Science Corporation 25 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 52 Wall construction using the EIFS cladding system
1121 Thermal Control
1313 1313
1313 1313
1313 131313
13 13 $
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 53 Thermal analysis of an EIFS wall system
Table 15 Calculated whole wall R-value for a EIFS wall system with 4rdquo of EPS
1122 Moisture Control
1313131313131313
131313amp1313
13131313
131313amp
13131313131313
13 13 13+ 13amp 131313
1313131313 131313) amp
1123 Constructability and Cost
131313131313
131313amp1313131313amp
131313131313 1313 13
1313amp
1124 Other Considerations
131313131313amp 13
13131313 131313
13amp13$1313131313
1313131313amp 131313131313
131313131313amp
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
D Conclusions
amp 1313
)- 13$13
13131313 1313
1313
Table 16 Summary of all calculated R-values
131313 amp
amp(
13amp 1313
13 ampamp(1313$
13amp) amp
amp13$ 13$
131313 amp )
( 131313$1313$13
amp+( 1313
13$1313$13
amp 13131313
1313131313 13
131313
13 $
) 13
131313$
$13
13
Building Science Corporation -) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 17 Hours of potential winter time air leakage condensation
13
) 1313amp$13
amp 13amp 13)
amp13amp$13
131313
13
1313
13
1313
Building Science Corporation (amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 18 Wall Comparison Chart
$$ 13$$13
$13
amp$
amp$13
1313
(
1313
$amp ( 13
$( $ (
13
$ 13 amp amp
13 13 amp
$13$1313$ 13$
amp
$ $13$ amp13 $13
13
13 $amp13
13$13 13
$ $ 13amp
amp
Building Science Corporation +) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313
13
13 1313
13
131313 1313
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
E Works Cited
9ADF8+amp+ 81$$=-amp-7gt9( amp00CAAI9
(8ltlt9-$amp+amp9lt-amp+lt(+lt+(ADF+amp+ 1$$
-amp-lt+ampC +1$$ -+lt+ M KCA -+9
(amp77amp - 9 2ampamp++
+amp$-$amp+913ampamp)327307CAAD9
9$$-+amp+ amp913ampamp 0CAAH9
(8ltlt9 9lt+ LL+ampL$19+(09
+amp77amp +amp19+amp$()-$$amp$900 ) $
0BJJF9
- amp79FA9amp($+(($amp amp+-$13+amp1$$9( amp7BJGE9
+amp17 amp7- 7 $$( $+7amp1213 -amp9 $$amp$
amp$-+8$amp+amp-ampampamp$$ $ampampamp
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=++13 G7CAAJgt9
279amp+- -ampamp2-$ -+ $amp + -amp$amp+
$2amp9 (((ampampampamp7-( 1+CJ=CAAHgt8DBBDBC9
-++-7139979139amp713997137amp13913913ampampamp913267113$amp5113)
- ampamp amp07amp8amp$+ -amp$amp7CAAI9
3713999amp4(13)( ) $ amp amp
+ amp07amp8amp$+ -amp$amp7CAAG9
(+amp7$$7ampampampamp$9 1+$(+amp13+-$amp+9amp
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(8ltlt9+(+9ltampamplt amp$ltamp09 MBGB=++ADBA7CAAJgt9
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$amp$-amp+ amp97CAAG9
-7 amp7amp-amp9( ( amp(amp0+8-$ampamp++7
CAAF9
Building Science Corporation GF wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
13 13
13
110 Case 10 Double Stud Wall with Spray Foam
amp 13 13
) 13 13
)13
amp 13 13
131313
13
13 131313
1313 13 1313 13
13
Figure 48 Double stud wall with 2 of spray foam and cellulose fill
1101 Thermal Control
$) 13
13(amp() $
13$
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 49 Therm analysis of double stud wall construction with spray foam
Table 13 Calculated whole wall R-value for a double stud wall system with 2rdquo spray foam
1102 Moisture Control
13 13 (13
13 13
13 1313 13
13 13
($$13(amp$$$13
13 1313 1313 13 13
13 13 13 $13 13
1313 amp+ 13
1313 amp1313 13
13 1313 amp
1313 13 13
1103 Constructability and Cost
13131313 13 13
13131313131313
Building Science Corporation )( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1104 Other Considerations
13 13 13 1313
131313(13 131313 1313 13 amp
13 13 (
131313 1313 13 13 13 13
13 (
111 Case 11 Offset Frame Wall with Exterior Spray Foam
131313 1313 13 1313
13 13 13 13( 13 1313131313 131313
13 1313$ 13 13 13(
13 13 13 13 13 13
$ 13 ( 1313 13 131313131313
1313 13 13( 1313
13 13 13(
13 13 13 13 13(
1313 ( 1313 13 13
1313 (1313 13 13 13 1313
1313 13 13( 1313
13 13 13$13 -++13 13
131313 1313 1313(13 13
13 13 13 )13
13 13 13 13 13 13 13 13
(
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 50 Offset frame wall construction with exterior spray foam
1111 Thermal Control
131313 13 1313131313
1313 131313
13 13 13131313
13 13 13 13 13 13 13
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 51 Therm analysis of an offset truss wall with exterior spray foam
Table 14 Calculated whole wall R-value for an offset framed wall with exterior spray foam
1112 Moisture Control
13
$ 13$
+amp13
+amp$
13 131313
1313 ()amp$13
13 13131313
1313$
1313
13
(-amp$
1113 Constructability and Cost
13 $13
1313 13 13 $
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($( $$
$ $($$($$+
1114 Other Considerations
$$amp$(amp$+
( $ $(($$
ampamp$amp$+
amp$+13 $-
$$(($
112 Case 12 Exterior Insulation Finish System (EIFS)
$(- 13()+
$ $
amp$$+amp$
-016532443405amp(+
13$$$$+
(amp $
$amp(amp$(+
$$ampamp 13$ampamp$(
$amp(+($$
amp$$$ $()+
($amp$13$$
($$ 13($$+
Building Science Corporation 25 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 52 Wall construction using the EIFS cladding system
1121 Thermal Control
1313 1313
1313 1313
1313 131313
13 13 $
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 53 Thermal analysis of an EIFS wall system
Table 15 Calculated whole wall R-value for a EIFS wall system with 4rdquo of EPS
1122 Moisture Control
1313131313131313
131313amp1313
13131313
131313amp
13131313131313
13 13 13+ 13amp 131313
1313131313 131313) amp
1123 Constructability and Cost
131313131313
131313amp1313131313amp
131313131313 1313 13
1313amp
1124 Other Considerations
131313131313amp 13
13131313 131313
13amp13$1313131313
1313131313amp 131313131313
131313131313amp
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
D Conclusions
amp 1313
)- 13$13
13131313 1313
1313
Table 16 Summary of all calculated R-values
131313 amp
amp(
13amp 1313
13 ampamp(1313$
13amp) amp
amp13$ 13$
131313 amp )
( 131313$1313$13
amp+( 1313
13$1313$13
amp 13131313
1313131313 13
131313
13 $
) 13
131313$
$13
13
Building Science Corporation -) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 17 Hours of potential winter time air leakage condensation
13
) 1313amp$13
amp 13amp 13)
amp13amp$13
131313
13
1313
13
1313
Building Science Corporation (amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 18 Wall Comparison Chart
$$ 13$$13
$13
amp$
amp$13
1313
(
1313
$amp ( 13
$( $ (
13
$ 13 amp amp
13 13 amp
$13$1313$ 13$
amp
$ $13$ amp13 $13
13
13 $amp13
13$13 13
$ $ 13amp
amp
Building Science Corporation +) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313
13
13 1313
13
131313 1313
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
E Works Cited
9ADF8+amp+ 81$$=-amp-7gt9( amp00CAAI9
(8ltlt9-$amp+amp9lt-amp+lt(+lt+(ADF+amp+ 1$$
-amp-lt+ampC +1$$ -+lt+ M KCA -+9
(amp77amp - 9 2ampamp++
+amp$-$amp+913ampamp)327307CAAD9
9$$-+amp+ amp913ampamp 0CAAH9
(8ltlt9 9lt+ LL+ampL$19+(09
+amp77amp +amp19+amp$()-$$amp$900 ) $
0BJJF9
- amp79FA9amp($+(($amp amp+-$13+amp1$$9( amp7BJGE9
+amp17 amp7- 7 $$( $+7amp1213 -amp9 $$amp$
amp$-+8$amp+amp-ampampamp$$ $ampampamp
$$$+9( amp07CAAH9
+-79((0131D7CAAH9 (8ltlt91--9lt M D(A5-M ampamp$(
=++13 G7CAAJgt9
279amp+- -ampamp2-$ -+ $amp + -amp$amp+
$2amp9 (((ampampampamp7-( 1+CJ=CAAHgt8DBBDBC9
-++-7139979139amp713997137amp13913913ampampamp913267113$amp5113)
- ampamp amp07amp8amp$+ -amp$amp7CAAI9
3713999amp4(13)( ) $ amp amp
+ amp07amp8amp$+ -amp$amp7CAAG9
(+amp7$$7ampampampamp$9 1+$(+amp13+-$amp+9amp
7DBDCE913+amp7 8+-+17BJJJ9
9(amp -amp-7$+++-9(( amp( ampamp0-1CAAC9
(8ltlt9+(+9ltampamplt amp$ltamp09 MBGB=++ADBA7CAAJgt9
$7amp amp7amp amp-913amp )amp amp(amp0$7amp8
$amp$-amp+ amp97CAAG9
-7 amp7amp-amp9( ( amp(amp0+8-$ampamp++7
CAAF9
Building Science Corporation GF wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
Figure 49 Therm analysis of double stud wall construction with spray foam
Table 13 Calculated whole wall R-value for a double stud wall system with 2rdquo spray foam
1102 Moisture Control
13 13 (13
13 13
13 1313 13
13 13
($$13(amp$$$13
13 1313 1313 13 13
13 13 13 $13 13
1313 amp+ 13
1313 amp1313 13
13 1313 amp
1313 13 13
1103 Constructability and Cost
13131313 13 13
13131313131313
Building Science Corporation )( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1104 Other Considerations
13 13 13 1313
131313(13 131313 1313 13 amp
13 13 (
131313 1313 13 13 13 13
13 (
111 Case 11 Offset Frame Wall with Exterior Spray Foam
131313 1313 13 1313
13 13 13 13( 13 1313131313 131313
13 1313$ 13 13 13(
13 13 13 13 13 13
$ 13 ( 1313 13 131313131313
1313 13 13( 1313
13 13 13(
13 13 13 13 13(
1313 ( 1313 13 13
1313 (1313 13 13 13 1313
1313 13 13( 1313
13 13 13$13 -++13 13
131313 1313 1313(13 13
13 13 13 )13
13 13 13 13 13 13 13 13
(
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 50 Offset frame wall construction with exterior spray foam
1111 Thermal Control
131313 13 1313131313
1313 131313
13 13 13131313
13 13 13 13 13 13 13
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 51 Therm analysis of an offset truss wall with exterior spray foam
Table 14 Calculated whole wall R-value for an offset framed wall with exterior spray foam
1112 Moisture Control
13
$ 13$
+amp13
+amp$
13 131313
1313 ()amp$13
13 13131313
1313$
1313
13
(-amp$
1113 Constructability and Cost
13 $13
1313 13 13 $
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($( $$
$ $($$($$+
1114 Other Considerations
$$amp$(amp$+
( $ $(($$
ampamp$amp$+
amp$+13 $-
$$(($
112 Case 12 Exterior Insulation Finish System (EIFS)
$(- 13()+
$ $
amp$$+amp$
-016532443405amp(+
13$$$$+
(amp $
$amp(amp$(+
$$ampamp 13$ampamp$(
$amp(+($$
amp$$$ $()+
($amp$13$$
($$ 13($$+
Building Science Corporation 25 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 52 Wall construction using the EIFS cladding system
1121 Thermal Control
1313 1313
1313 1313
1313 131313
13 13 $
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 53 Thermal analysis of an EIFS wall system
Table 15 Calculated whole wall R-value for a EIFS wall system with 4rdquo of EPS
1122 Moisture Control
1313131313131313
131313amp1313
13131313
131313amp
13131313131313
13 13 13+ 13amp 131313
1313131313 131313) amp
1123 Constructability and Cost
131313131313
131313amp1313131313amp
131313131313 1313 13
1313amp
1124 Other Considerations
131313131313amp 13
13131313 131313
13amp13$1313131313
1313131313amp 131313131313
131313131313amp
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
D Conclusions
amp 1313
)- 13$13
13131313 1313
1313
Table 16 Summary of all calculated R-values
131313 amp
amp(
13amp 1313
13 ampamp(1313$
13amp) amp
amp13$ 13$
131313 amp )
( 131313$1313$13
amp+( 1313
13$1313$13
amp 13131313
1313131313 13
131313
13 $
) 13
131313$
$13
13
Building Science Corporation -) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 17 Hours of potential winter time air leakage condensation
13
) 1313amp$13
amp 13amp 13)
amp13amp$13
131313
13
1313
13
1313
Building Science Corporation (amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 18 Wall Comparison Chart
$$ 13$$13
$13
amp$
amp$13
1313
(
1313
$amp ( 13
$( $ (
13
$ 13 amp amp
13 13 amp
$13$1313$ 13$
amp
$ $13$ amp13 $13
13
13 $amp13
13$13 13
$ $ 13amp
amp
Building Science Corporation +) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313
13
13 1313
13
131313 1313
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
E Works Cited
9ADF8+amp+ 81$$=-amp-7gt9( amp00CAAI9
(8ltlt9-$amp+amp9lt-amp+lt(+lt+(ADF+amp+ 1$$
-amp-lt+ampC +1$$ -+lt+ M KCA -+9
(amp77amp - 9 2ampamp++
+amp$-$amp+913ampamp)327307CAAD9
9$$-+amp+ amp913ampamp 0CAAH9
(8ltlt9 9lt+ LL+ampL$19+(09
+amp77amp +amp19+amp$()-$$amp$900 ) $
0BJJF9
- amp79FA9amp($+(($amp amp+-$13+amp1$$9( amp7BJGE9
+amp17 amp7- 7 $$( $+7amp1213 -amp9 $$amp$
amp$-+8$amp+amp-ampampamp$$ $ampampamp
$$$+9( amp07CAAH9
+-79((0131D7CAAH9 (8ltlt91--9lt M D(A5-M ampamp$(
=++13 G7CAAJgt9
279amp+- -ampamp2-$ -+ $amp + -amp$amp+
$2amp9 (((ampampampamp7-( 1+CJ=CAAHgt8DBBDBC9
-++-7139979139amp713997137amp13913913ampampamp913267113$amp5113)
- ampamp amp07amp8amp$+ -amp$amp7CAAI9
3713999amp4(13)( ) $ amp amp
+ amp07amp8amp$+ -amp$amp7CAAG9
(+amp7$$7ampampampamp$9 1+$(+amp13+-$amp+9amp
7DBDCE913+amp7 8+-+17BJJJ9
9(amp -amp-7$+++-9(( amp( ampamp0-1CAAC9
(8ltlt9+(+9ltampamplt amp$ltamp09 MBGB=++ADBA7CAAJgt9
$7amp amp7amp amp-913amp )amp amp(amp0$7amp8
$amp$-amp+ amp97CAAG9
-7 amp7amp-amp9( ( amp(amp0+8-$ampamp++7
CAAF9
Building Science Corporation GF wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
1104 Other Considerations
13 13 13 1313
131313(13 131313 1313 13 amp
13 13 (
131313 1313 13 13 13 13
13 (
111 Case 11 Offset Frame Wall with Exterior Spray Foam
131313 1313 13 1313
13 13 13 13( 13 1313131313 131313
13 1313$ 13 13 13(
13 13 13 13 13 13
$ 13 ( 1313 13 131313131313
1313 13 13( 1313
13 13 13(
13 13 13 13 13(
1313 ( 1313 13 13
1313 (1313 13 13 13 1313
1313 13 13( 1313
13 13 13$13 -++13 13
131313 1313 1313(13 13
13 13 13 )13
13 13 13 13 13 13 13 13
(
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 50 Offset frame wall construction with exterior spray foam
1111 Thermal Control
131313 13 1313131313
1313 131313
13 13 13131313
13 13 13 13 13 13 13
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 51 Therm analysis of an offset truss wall with exterior spray foam
Table 14 Calculated whole wall R-value for an offset framed wall with exterior spray foam
1112 Moisture Control
13
$ 13$
+amp13
+amp$
13 131313
1313 ()amp$13
13 13131313
1313$
1313
13
(-amp$
1113 Constructability and Cost
13 $13
1313 13 13 $
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($( $$
$ $($$($$+
1114 Other Considerations
$$amp$(amp$+
( $ $(($$
ampamp$amp$+
amp$+13 $-
$$(($
112 Case 12 Exterior Insulation Finish System (EIFS)
$(- 13()+
$ $
amp$$+amp$
-016532443405amp(+
13$$$$+
(amp $
$amp(amp$(+
$$ampamp 13$ampamp$(
$amp(+($$
amp$$$ $()+
($amp$13$$
($$ 13($$+
Building Science Corporation 25 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 52 Wall construction using the EIFS cladding system
1121 Thermal Control
1313 1313
1313 1313
1313 131313
13 13 $
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 53 Thermal analysis of an EIFS wall system
Table 15 Calculated whole wall R-value for a EIFS wall system with 4rdquo of EPS
1122 Moisture Control
1313131313131313
131313amp1313
13131313
131313amp
13131313131313
13 13 13+ 13amp 131313
1313131313 131313) amp
1123 Constructability and Cost
131313131313
131313amp1313131313amp
131313131313 1313 13
1313amp
1124 Other Considerations
131313131313amp 13
13131313 131313
13amp13$1313131313
1313131313amp 131313131313
131313131313amp
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
D Conclusions
amp 1313
)- 13$13
13131313 1313
1313
Table 16 Summary of all calculated R-values
131313 amp
amp(
13amp 1313
13 ampamp(1313$
13amp) amp
amp13$ 13$
131313 amp )
( 131313$1313$13
amp+( 1313
13$1313$13
amp 13131313
1313131313 13
131313
13 $
) 13
131313$
$13
13
Building Science Corporation -) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 17 Hours of potential winter time air leakage condensation
13
) 1313amp$13
amp 13amp 13)
amp13amp$13
131313
13
1313
13
1313
Building Science Corporation (amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 18 Wall Comparison Chart
$$ 13$$13
$13
amp$
amp$13
1313
(
1313
$amp ( 13
$( $ (
13
$ 13 amp amp
13 13 amp
$13$1313$ 13$
amp
$ $13$ amp13 $13
13
13 $amp13
13$13 13
$ $ 13amp
amp
Building Science Corporation +) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313
13
13 1313
13
131313 1313
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
E Works Cited
9ADF8+amp+ 81$$=-amp-7gt9( amp00CAAI9
(8ltlt9-$amp+amp9lt-amp+lt(+lt+(ADF+amp+ 1$$
-amp-lt+ampC +1$$ -+lt+ M KCA -+9
(amp77amp - 9 2ampamp++
+amp$-$amp+913ampamp)327307CAAD9
9$$-+amp+ amp913ampamp 0CAAH9
(8ltlt9 9lt+ LL+ampL$19+(09
+amp77amp +amp19+amp$()-$$amp$900 ) $
0BJJF9
- amp79FA9amp($+(($amp amp+-$13+amp1$$9( amp7BJGE9
+amp17 amp7- 7 $$( $+7amp1213 -amp9 $$amp$
amp$-+8$amp+amp-ampampamp$$ $ampampamp
$$$+9( amp07CAAH9
+-79((0131D7CAAH9 (8ltlt91--9lt M D(A5-M ampamp$(
=++13 G7CAAJgt9
279amp+- -ampamp2-$ -+ $amp + -amp$amp+
$2amp9 (((ampampampamp7-( 1+CJ=CAAHgt8DBBDBC9
-++-7139979139amp713997137amp13913913ampampamp913267113$amp5113)
- ampamp amp07amp8amp$+ -amp$amp7CAAI9
3713999amp4(13)( ) $ amp amp
+ amp07amp8amp$+ -amp$amp7CAAG9
(+amp7$$7ampampampamp$9 1+$(+amp13+-$amp+9amp
7DBDCE913+amp7 8+-+17BJJJ9
9(amp -amp-7$+++-9(( amp( ampamp0-1CAAC9
(8ltlt9+(+9ltampamplt amp$ltamp09 MBGB=++ADBA7CAAJgt9
$7amp amp7amp amp-913amp )amp amp(amp0$7amp8
$amp$-amp+ amp97CAAG9
-7 amp7amp-amp9( ( amp(amp0+8-$ampamp++7
CAAF9
Building Science Corporation GF wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
Figure 50 Offset frame wall construction with exterior spray foam
1111 Thermal Control
131313 13 1313131313
1313 131313
13 13 13131313
13 13 13 13 13 13 13
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 51 Therm analysis of an offset truss wall with exterior spray foam
Table 14 Calculated whole wall R-value for an offset framed wall with exterior spray foam
1112 Moisture Control
13
$ 13$
+amp13
+amp$
13 131313
1313 ()amp$13
13 13131313
1313$
1313
13
(-amp$
1113 Constructability and Cost
13 $13
1313 13 13 $
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($( $$
$ $($$($$+
1114 Other Considerations
$$amp$(amp$+
( $ $(($$
ampamp$amp$+
amp$+13 $-
$$(($
112 Case 12 Exterior Insulation Finish System (EIFS)
$(- 13()+
$ $
amp$$+amp$
-016532443405amp(+
13$$$$+
(amp $
$amp(amp$(+
$$ampamp 13$ampamp$(
$amp(+($$
amp$$$ $()+
($amp$13$$
($$ 13($$+
Building Science Corporation 25 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 52 Wall construction using the EIFS cladding system
1121 Thermal Control
1313 1313
1313 1313
1313 131313
13 13 $
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 53 Thermal analysis of an EIFS wall system
Table 15 Calculated whole wall R-value for a EIFS wall system with 4rdquo of EPS
1122 Moisture Control
1313131313131313
131313amp1313
13131313
131313amp
13131313131313
13 13 13+ 13amp 131313
1313131313 131313) amp
1123 Constructability and Cost
131313131313
131313amp1313131313amp
131313131313 1313 13
1313amp
1124 Other Considerations
131313131313amp 13
13131313 131313
13amp13$1313131313
1313131313amp 131313131313
131313131313amp
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
D Conclusions
amp 1313
)- 13$13
13131313 1313
1313
Table 16 Summary of all calculated R-values
131313 amp
amp(
13amp 1313
13 ampamp(1313$
13amp) amp
amp13$ 13$
131313 amp )
( 131313$1313$13
amp+( 1313
13$1313$13
amp 13131313
1313131313 13
131313
13 $
) 13
131313$
$13
13
Building Science Corporation -) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 17 Hours of potential winter time air leakage condensation
13
) 1313amp$13
amp 13amp 13)
amp13amp$13
131313
13
1313
13
1313
Building Science Corporation (amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 18 Wall Comparison Chart
$$ 13$$13
$13
amp$
amp$13
1313
(
1313
$amp ( 13
$( $ (
13
$ 13 amp amp
13 13 amp
$13$1313$ 13$
amp
$ $13$ amp13 $13
13
13 $amp13
13$13 13
$ $ 13amp
amp
Building Science Corporation +) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313
13
13 1313
13
131313 1313
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
E Works Cited
9ADF8+amp+ 81$$=-amp-7gt9( amp00CAAI9
(8ltlt9-$amp+amp9lt-amp+lt(+lt+(ADF+amp+ 1$$
-amp-lt+ampC +1$$ -+lt+ M KCA -+9
(amp77amp - 9 2ampamp++
+amp$-$amp+913ampamp)327307CAAD9
9$$-+amp+ amp913ampamp 0CAAH9
(8ltlt9 9lt+ LL+ampL$19+(09
+amp77amp +amp19+amp$()-$$amp$900 ) $
0BJJF9
- amp79FA9amp($+(($amp amp+-$13+amp1$$9( amp7BJGE9
+amp17 amp7- 7 $$( $+7amp1213 -amp9 $$amp$
amp$-+8$amp+amp-ampampamp$$ $ampampamp
$$$+9( amp07CAAH9
+-79((0131D7CAAH9 (8ltlt91--9lt M D(A5-M ampamp$(
=++13 G7CAAJgt9
279amp+- -ampamp2-$ -+ $amp + -amp$amp+
$2amp9 (((ampampampamp7-( 1+CJ=CAAHgt8DBBDBC9
-++-7139979139amp713997137amp13913913ampampamp913267113$amp5113)
- ampamp amp07amp8amp$+ -amp$amp7CAAI9
3713999amp4(13)( ) $ amp amp
+ amp07amp8amp$+ -amp$amp7CAAG9
(+amp7$$7ampampampamp$9 1+$(+amp13+-$amp+9amp
7DBDCE913+amp7 8+-+17BJJJ9
9(amp -amp-7$+++-9(( amp( ampamp0-1CAAC9
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$7amp amp7amp amp-913amp )amp amp(amp0$7amp8
$amp$-amp+ amp97CAAG9
-7 amp7amp-amp9( ( amp(amp0+8-$ampamp++7
CAAF9
Building Science Corporation GF wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
Figure 51 Therm analysis of an offset truss wall with exterior spray foam
Table 14 Calculated whole wall R-value for an offset framed wall with exterior spray foam
1112 Moisture Control
13
$ 13$
+amp13
+amp$
13 131313
1313 ()amp$13
13 13131313
1313$
1313
13
(-amp$
1113 Constructability and Cost
13 $13
1313 13 13 $
Building Science Corporation wwwbuildingsciencecom
30 Forest St Somerville MA 02143
$($( $$
$ $($$($$+
1114 Other Considerations
$$amp$(amp$+
( $ $(($$
ampamp$amp$+
amp$+13 $-
$$(($
112 Case 12 Exterior Insulation Finish System (EIFS)
$(- 13()+
$ $
amp$$+amp$
-016532443405amp(+
13$$$$+
(amp $
$amp(amp$(+
$$ampamp 13$ampamp$(
$amp(+($$
amp$$$ $()+
($amp$13$$
($$ 13($$+
Building Science Corporation 25 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 52 Wall construction using the EIFS cladding system
1121 Thermal Control
1313 1313
1313 1313
1313 131313
13 13 $
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 53 Thermal analysis of an EIFS wall system
Table 15 Calculated whole wall R-value for a EIFS wall system with 4rdquo of EPS
1122 Moisture Control
1313131313131313
131313amp1313
13131313
131313amp
13131313131313
13 13 13+ 13amp 131313
1313131313 131313) amp
1123 Constructability and Cost
131313131313
131313amp1313131313amp
131313131313 1313 13
1313amp
1124 Other Considerations
131313131313amp 13
13131313 131313
13amp13$1313131313
1313131313amp 131313131313
131313131313amp
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
D Conclusions
amp 1313
)- 13$13
13131313 1313
1313
Table 16 Summary of all calculated R-values
131313 amp
amp(
13amp 1313
13 ampamp(1313$
13amp) amp
amp13$ 13$
131313 amp )
( 131313$1313$13
amp+( 1313
13$1313$13
amp 13131313
1313131313 13
131313
13 $
) 13
131313$
$13
13
Building Science Corporation -) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 17 Hours of potential winter time air leakage condensation
13
) 1313amp$13
amp 13amp 13)
amp13amp$13
131313
13
1313
13
1313
Building Science Corporation (amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 18 Wall Comparison Chart
$$ 13$$13
$13
amp$
amp$13
1313
(
1313
$amp ( 13
$( $ (
13
$ 13 amp amp
13 13 amp
$13$1313$ 13$
amp
$ $13$ amp13 $13
13
13 $amp13
13$13 13
$ $ 13amp
amp
Building Science Corporation +) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313
13
13 1313
13
131313 1313
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
E Works Cited
9ADF8+amp+ 81$$=-amp-7gt9( amp00CAAI9
(8ltlt9-$amp+amp9lt-amp+lt(+lt+(ADF+amp+ 1$$
-amp-lt+ampC +1$$ -+lt+ M KCA -+9
(amp77amp - 9 2ampamp++
+amp$-$amp+913ampamp)327307CAAD9
9$$-+amp+ amp913ampamp 0CAAH9
(8ltlt9 9lt+ LL+ampL$19+(09
+amp77amp +amp19+amp$()-$$amp$900 ) $
0BJJF9
- amp79FA9amp($+(($amp amp+-$13+amp1$$9( amp7BJGE9
+amp17 amp7- 7 $$( $+7amp1213 -amp9 $$amp$
amp$-+8$amp+amp-ampampamp$$ $ampampamp
$$$+9( amp07CAAH9
+-79((0131D7CAAH9 (8ltlt91--9lt M D(A5-M ampamp$(
=++13 G7CAAJgt9
279amp+- -ampamp2-$ -+ $amp + -amp$amp+
$2amp9 (((ampampampamp7-( 1+CJ=CAAHgt8DBBDBC9
-++-7139979139amp713997137amp13913913ampampamp913267113$amp5113)
- ampamp amp07amp8amp$+ -amp$amp7CAAI9
3713999amp4(13)( ) $ amp amp
+ amp07amp8amp$+ -amp$amp7CAAG9
(+amp7$$7ampampampamp$9 1+$(+amp13+-$amp+9amp
7DBDCE913+amp7 8+-+17BJJJ9
9(amp -amp-7$+++-9(( amp( ampamp0-1CAAC9
(8ltlt9+(+9ltampamplt amp$ltamp09 MBGB=++ADBA7CAAJgt9
$7amp amp7amp amp-913amp )amp amp(amp0$7amp8
$amp$-amp+ amp97CAAG9
-7 amp7amp-amp9( ( amp(amp0+8-$ampamp++7
CAAF9
Building Science Corporation GF wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
$($( $$
$ $($$($$+
1114 Other Considerations
$$amp$(amp$+
( $ $(($$
ampamp$amp$+
amp$+13 $-
$$(($
112 Case 12 Exterior Insulation Finish System (EIFS)
$(- 13()+
$ $
amp$$+amp$
-016532443405amp(+
13$$$$+
(amp $
$amp(amp$(+
$$ampamp 13$ampamp$(
$amp(+($$
amp$$$ $()+
($amp$13$$
($$ 13($$+
Building Science Corporation 25 wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 52 Wall construction using the EIFS cladding system
1121 Thermal Control
1313 1313
1313 1313
1313 131313
13 13 $
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 53 Thermal analysis of an EIFS wall system
Table 15 Calculated whole wall R-value for a EIFS wall system with 4rdquo of EPS
1122 Moisture Control
1313131313131313
131313amp1313
13131313
131313amp
13131313131313
13 13 13+ 13amp 131313
1313131313 131313) amp
1123 Constructability and Cost
131313131313
131313amp1313131313amp
131313131313 1313 13
1313amp
1124 Other Considerations
131313131313amp 13
13131313 131313
13amp13$1313131313
1313131313amp 131313131313
131313131313amp
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
D Conclusions
amp 1313
)- 13$13
13131313 1313
1313
Table 16 Summary of all calculated R-values
131313 amp
amp(
13amp 1313
13 ampamp(1313$
13amp) amp
amp13$ 13$
131313 amp )
( 131313$1313$13
amp+( 1313
13$1313$13
amp 13131313
1313131313 13
131313
13 $
) 13
131313$
$13
13
Building Science Corporation -) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 17 Hours of potential winter time air leakage condensation
13
) 1313amp$13
amp 13amp 13)
amp13amp$13
131313
13
1313
13
1313
Building Science Corporation (amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 18 Wall Comparison Chart
$$ 13$$13
$13
amp$
amp$13
1313
(
1313
$amp ( 13
$( $ (
13
$ 13 amp amp
13 13 amp
$13$1313$ 13$
amp
$ $13$ amp13 $13
13
13 $amp13
13$13 13
$ $ 13amp
amp
Building Science Corporation +) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313
13
13 1313
13
131313 1313
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
E Works Cited
9ADF8+amp+ 81$$=-amp-7gt9( amp00CAAI9
(8ltlt9-$amp+amp9lt-amp+lt(+lt+(ADF+amp+ 1$$
-amp-lt+ampC +1$$ -+lt+ M KCA -+9
(amp77amp - 9 2ampamp++
+amp$-$amp+913ampamp)327307CAAD9
9$$-+amp+ amp913ampamp 0CAAH9
(8ltlt9 9lt+ LL+ampL$19+(09
+amp77amp +amp19+amp$()-$$amp$900 ) $
0BJJF9
- amp79FA9amp($+(($amp amp+-$13+amp1$$9( amp7BJGE9
+amp17 amp7- 7 $$( $+7amp1213 -amp9 $$amp$
amp$-+8$amp+amp-ampampamp$$ $ampampamp
$$$+9( amp07CAAH9
+-79((0131D7CAAH9 (8ltlt91--9lt M D(A5-M ampamp$(
=++13 G7CAAJgt9
279amp+- -ampamp2-$ -+ $amp + -amp$amp+
$2amp9 (((ampampampamp7-( 1+CJ=CAAHgt8DBBDBC9
-++-7139979139amp713997137amp13913913ampampamp913267113$amp5113)
- ampamp amp07amp8amp$+ -amp$amp7CAAI9
3713999amp4(13)( ) $ amp amp
+ amp07amp8amp$+ -amp$amp7CAAG9
(+amp7$$7ampampampamp$9 1+$(+amp13+-$amp+9amp
7DBDCE913+amp7 8+-+17BJJJ9
9(amp -amp-7$+++-9(( amp( ampamp0-1CAAC9
(8ltlt9+(+9ltampamplt amp$ltamp09 MBGB=++ADBA7CAAJgt9
$7amp amp7amp amp-913amp )amp amp(amp0$7amp8
$amp$-amp+ amp97CAAG9
-7 amp7amp-amp9( ( amp(amp0+8-$ampamp++7
CAAF9
Building Science Corporation GF wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
Figure 52 Wall construction using the EIFS cladding system
1121 Thermal Control
1313 1313
1313 1313
1313 131313
13 13 $
Building Science Corporation amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Figure 53 Thermal analysis of an EIFS wall system
Table 15 Calculated whole wall R-value for a EIFS wall system with 4rdquo of EPS
1122 Moisture Control
1313131313131313
131313amp1313
13131313
131313amp
13131313131313
13 13 13+ 13amp 131313
1313131313 131313) amp
1123 Constructability and Cost
131313131313
131313amp1313131313amp
131313131313 1313 13
1313amp
1124 Other Considerations
131313131313amp 13
13131313 131313
13amp13$1313131313
1313131313amp 131313131313
131313131313amp
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
D Conclusions
amp 1313
)- 13$13
13131313 1313
1313
Table 16 Summary of all calculated R-values
131313 amp
amp(
13amp 1313
13 ampamp(1313$
13amp) amp
amp13$ 13$
131313 amp )
( 131313$1313$13
amp+( 1313
13$1313$13
amp 13131313
1313131313 13
131313
13 $
) 13
131313$
$13
13
Building Science Corporation -) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 17 Hours of potential winter time air leakage condensation
13
) 1313amp$13
amp 13amp 13)
amp13amp$13
131313
13
1313
13
1313
Building Science Corporation (amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 18 Wall Comparison Chart
$$ 13$$13
$13
amp$
amp$13
1313
(
1313
$amp ( 13
$( $ (
13
$ 13 amp amp
13 13 amp
$13$1313$ 13$
amp
$ $13$ amp13 $13
13
13 $amp13
13$13 13
$ $ 13amp
amp
Building Science Corporation +) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313
13
13 1313
13
131313 1313
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
E Works Cited
9ADF8+amp+ 81$$=-amp-7gt9( amp00CAAI9
(8ltlt9-$amp+amp9lt-amp+lt(+lt+(ADF+amp+ 1$$
-amp-lt+ampC +1$$ -+lt+ M KCA -+9
(amp77amp - 9 2ampamp++
+amp$-$amp+913ampamp)327307CAAD9
9$$-+amp+ amp913ampamp 0CAAH9
(8ltlt9 9lt+ LL+ampL$19+(09
+amp77amp +amp19+amp$()-$$amp$900 ) $
0BJJF9
- amp79FA9amp($+(($amp amp+-$13+amp1$$9( amp7BJGE9
+amp17 amp7- 7 $$( $+7amp1213 -amp9 $$amp$
amp$-+8$amp+amp-ampampamp$$ $ampampamp
$$$+9( amp07CAAH9
+-79((0131D7CAAH9 (8ltlt91--9lt M D(A5-M ampamp$(
=++13 G7CAAJgt9
279amp+- -ampamp2-$ -+ $amp + -amp$amp+
$2amp9 (((ampampampamp7-( 1+CJ=CAAHgt8DBBDBC9
-++-7139979139amp713997137amp13913913ampampamp913267113$amp5113)
- ampamp amp07amp8amp$+ -amp$amp7CAAI9
3713999amp4(13)( ) $ amp amp
+ amp07amp8amp$+ -amp$amp7CAAG9
(+amp7$$7ampampampamp$9 1+$(+amp13+-$amp+9amp
7DBDCE913+amp7 8+-+17BJJJ9
9(amp -amp-7$+++-9(( amp( ampamp0-1CAAC9
(8ltlt9+(+9ltampamplt amp$ltamp09 MBGB=++ADBA7CAAJgt9
$7amp amp7amp amp-913amp )amp amp(amp0$7amp8
$amp$-amp+ amp97CAAG9
-7 amp7amp-amp9( ( amp(amp0+8-$ampamp++7
CAAF9
Building Science Corporation GF wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
Figure 53 Thermal analysis of an EIFS wall system
Table 15 Calculated whole wall R-value for a EIFS wall system with 4rdquo of EPS
1122 Moisture Control
1313131313131313
131313amp1313
13131313
131313amp
13131313131313
13 13 13+ 13amp 131313
1313131313 131313) amp
1123 Constructability and Cost
131313131313
131313amp1313131313amp
131313131313 1313 13
1313amp
1124 Other Considerations
131313131313amp 13
13131313 131313
13amp13$1313131313
1313131313amp 131313131313
131313131313amp
Building Science Corporation ( wwwbuildingsciencecom
30 Forest St Somerville MA 02143
D Conclusions
amp 1313
)- 13$13
13131313 1313
1313
Table 16 Summary of all calculated R-values
131313 amp
amp(
13amp 1313
13 ampamp(1313$
13amp) amp
amp13$ 13$
131313 amp )
( 131313$1313$13
amp+( 1313
13$1313$13
amp 13131313
1313131313 13
131313
13 $
) 13
131313$
$13
13
Building Science Corporation -) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 17 Hours of potential winter time air leakage condensation
13
) 1313amp$13
amp 13amp 13)
amp13amp$13
131313
13
1313
13
1313
Building Science Corporation (amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 18 Wall Comparison Chart
$$ 13$$13
$13
amp$
amp$13
1313
(
1313
$amp ( 13
$( $ (
13
$ 13 amp amp
13 13 amp
$13$1313$ 13$
amp
$ $13$ amp13 $13
13
13 $amp13
13$13 13
$ $ 13amp
amp
Building Science Corporation +) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313
13
13 1313
13
131313 1313
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
E Works Cited
9ADF8+amp+ 81$$=-amp-7gt9( amp00CAAI9
(8ltlt9-$amp+amp9lt-amp+lt(+lt+(ADF+amp+ 1$$
-amp-lt+ampC +1$$ -+lt+ M KCA -+9
(amp77amp - 9 2ampamp++
+amp$-$amp+913ampamp)327307CAAD9
9$$-+amp+ amp913ampamp 0CAAH9
(8ltlt9 9lt+ LL+ampL$19+(09
+amp77amp +amp19+amp$()-$$amp$900 ) $
0BJJF9
- amp79FA9amp($+(($amp amp+-$13+amp1$$9( amp7BJGE9
+amp17 amp7- 7 $$( $+7amp1213 -amp9 $$amp$
amp$-+8$amp+amp-ampampamp$$ $ampampamp
$$$+9( amp07CAAH9
+-79((0131D7CAAH9 (8ltlt91--9lt M D(A5-M ampamp$(
=++13 G7CAAJgt9
279amp+- -ampamp2-$ -+ $amp + -amp$amp+
$2amp9 (((ampampampamp7-( 1+CJ=CAAHgt8DBBDBC9
-++-7139979139amp713997137amp13913913ampampamp913267113$amp5113)
- ampamp amp07amp8amp$+ -amp$amp7CAAI9
3713999amp4(13)( ) $ amp amp
+ amp07amp8amp$+ -amp$amp7CAAG9
(+amp7$$7ampampampamp$9 1+$(+amp13+-$amp+9amp
7DBDCE913+amp7 8+-+17BJJJ9
9(amp -amp-7$+++-9(( amp( ampamp0-1CAAC9
(8ltlt9+(+9ltampamplt amp$ltamp09 MBGB=++ADBA7CAAJgt9
$7amp amp7amp amp-913amp )amp amp(amp0$7amp8
$amp$-amp+ amp97CAAG9
-7 amp7amp-amp9( ( amp(amp0+8-$ampamp++7
CAAF9
Building Science Corporation GF wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
D Conclusions
amp 1313
)- 13$13
13131313 1313
1313
Table 16 Summary of all calculated R-values
131313 amp
amp(
13amp 1313
13 ampamp(1313$
13amp) amp
amp13$ 13$
131313 amp )
( 131313$1313$13
amp+( 1313
13$1313$13
amp 13131313
1313131313 13
131313
13 $
) 13
131313$
$13
13
Building Science Corporation -) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 17 Hours of potential winter time air leakage condensation
13
) 1313amp$13
amp 13amp 13)
amp13amp$13
131313
13
1313
13
1313
Building Science Corporation (amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 18 Wall Comparison Chart
$$ 13$$13
$13
amp$
amp$13
1313
(
1313
$amp ( 13
$( $ (
13
$ 13 amp amp
13 13 amp
$13$1313$ 13$
amp
$ $13$ amp13 $13
13
13 $amp13
13$13 13
$ $ 13amp
amp
Building Science Corporation +) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313
13
13 1313
13
131313 1313
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
E Works Cited
9ADF8+amp+ 81$$=-amp-7gt9( amp00CAAI9
(8ltlt9-$amp+amp9lt-amp+lt(+lt+(ADF+amp+ 1$$
-amp-lt+ampC +1$$ -+lt+ M KCA -+9
(amp77amp - 9 2ampamp++
+amp$-$amp+913ampamp)327307CAAD9
9$$-+amp+ amp913ampamp 0CAAH9
(8ltlt9 9lt+ LL+ampL$19+(09
+amp77amp +amp19+amp$()-$$amp$900 ) $
0BJJF9
- amp79FA9amp($+(($amp amp+-$13+amp1$$9( amp7BJGE9
+amp17 amp7- 7 $$( $+7amp1213 -amp9 $$amp$
amp$-+8$amp+amp-ampampamp$$ $ampampamp
$$$+9( amp07CAAH9
+-79((0131D7CAAH9 (8ltlt91--9lt M D(A5-M ampamp$(
=++13 G7CAAJgt9
279amp+- -ampamp2-$ -+ $amp + -amp$amp+
$2amp9 (((ampampampamp7-( 1+CJ=CAAHgt8DBBDBC9
-++-7139979139amp713997137amp13913913ampampamp913267113$amp5113)
- ampamp amp07amp8amp$+ -amp$amp7CAAI9
3713999amp4(13)( ) $ amp amp
+ amp07amp8amp$+ -amp$amp7CAAG9
(+amp7$$7ampampampamp$9 1+$(+amp13+-$amp+9amp
7DBDCE913+amp7 8+-+17BJJJ9
9(amp -amp-7$+++-9(( amp( ampamp0-1CAAC9
(8ltlt9+(+9ltampamplt amp$ltamp09 MBGB=++ADBA7CAAJgt9
$7amp amp7amp amp-913amp )amp amp(amp0$7amp8
$amp$-amp+ amp97CAAG9
-7 amp7amp-amp9( ( amp(amp0+8-$ampamp++7
CAAF9
Building Science Corporation GF wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
Table 17 Hours of potential winter time air leakage condensation
13
) 1313amp$13
amp 13amp 13)
amp13amp$13
131313
13
1313
13
1313
Building Science Corporation (amp wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Table 18 Wall Comparison Chart
$$ 13$$13
$13
amp$
amp$13
1313
(
1313
$amp ( 13
$( $ (
13
$ 13 amp amp
13 13 amp
$13$1313$ 13$
amp
$ $13$ amp13 $13
13
13 $amp13
13$13 13
$ $ 13amp
amp
Building Science Corporation +) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313
13
13 1313
13
131313 1313
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
E Works Cited
9ADF8+amp+ 81$$=-amp-7gt9( amp00CAAI9
(8ltlt9-$amp+amp9lt-amp+lt(+lt+(ADF+amp+ 1$$
-amp-lt+ampC +1$$ -+lt+ M KCA -+9
(amp77amp - 9 2ampamp++
+amp$-$amp+913ampamp)327307CAAD9
9$$-+amp+ amp913ampamp 0CAAH9
(8ltlt9 9lt+ LL+ampL$19+(09
+amp77amp +amp19+amp$()-$$amp$900 ) $
0BJJF9
- amp79FA9amp($+(($amp amp+-$13+amp1$$9( amp7BJGE9
+amp17 amp7- 7 $$( $+7amp1213 -amp9 $$amp$
amp$-+8$amp+amp-ampampamp$$ $ampampamp
$$$+9( amp07CAAH9
+-79((0131D7CAAH9 (8ltlt91--9lt M D(A5-M ampamp$(
=++13 G7CAAJgt9
279amp+- -ampamp2-$ -+ $amp + -amp$amp+
$2amp9 (((ampampampamp7-( 1+CJ=CAAHgt8DBBDBC9
-++-7139979139amp713997137amp13913913ampampamp913267113$amp5113)
- ampamp amp07amp8amp$+ -amp$amp7CAAI9
3713999amp4(13)( ) $ amp amp
+ amp07amp8amp$+ -amp$amp7CAAG9
(+amp7$$7ampampampamp$9 1+$(+amp13+-$amp+9amp
7DBDCE913+amp7 8+-+17BJJJ9
9(amp -amp-7$+++-9(( amp( ampamp0-1CAAC9
(8ltlt9+(+9ltampamplt amp$ltamp09 MBGB=++ADBA7CAAJgt9
$7amp amp7amp amp-913amp )amp amp(amp0$7amp8
$amp$-amp+ amp97CAAG9
-7 amp7amp-amp9( ( amp(amp0+8-$ampamp++7
CAAF9
Building Science Corporation GF wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
Table 18 Wall Comparison Chart
$$ 13$$13
$13
amp$
amp$13
1313
(
1313
$amp ( 13
$( $ (
13
$ 13 amp amp
13 13 amp
$13$1313$ 13$
amp
$ $13$ amp13 $13
13
13 $amp13
13$13 13
$ $ 13amp
amp
Building Science Corporation +) wwwbuildingsciencecom
30 Forest St Somerville MA 02143
1313
13
13 1313
13
131313 1313
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
E Works Cited
9ADF8+amp+ 81$$=-amp-7gt9( amp00CAAI9
(8ltlt9-$amp+amp9lt-amp+lt(+lt+(ADF+amp+ 1$$
-amp-lt+ampC +1$$ -+lt+ M KCA -+9
(amp77amp - 9 2ampamp++
+amp$-$amp+913ampamp)327307CAAD9
9$$-+amp+ amp913ampamp 0CAAH9
(8ltlt9 9lt+ LL+ampL$19+(09
+amp77amp +amp19+amp$()-$$amp$900 ) $
0BJJF9
- amp79FA9amp($+(($amp amp+-$13+amp1$$9( amp7BJGE9
+amp17 amp7- 7 $$( $+7amp1213 -amp9 $$amp$
amp$-+8$amp+amp-ampampamp$$ $ampampamp
$$$+9( amp07CAAH9
+-79((0131D7CAAH9 (8ltlt91--9lt M D(A5-M ampamp$(
=++13 G7CAAJgt9
279amp+- -ampamp2-$ -+ $amp + -amp$amp+
$2amp9 (((ampampampamp7-( 1+CJ=CAAHgt8DBBDBC9
-++-7139979139amp713997137amp13913913ampampamp913267113$amp5113)
- ampamp amp07amp8amp$+ -amp$amp7CAAI9
3713999amp4(13)( ) $ amp amp
+ amp07amp8amp$+ -amp$amp7CAAG9
(+amp7$$7ampampampamp$9 1+$(+amp13+-$amp+9amp
7DBDCE913+amp7 8+-+17BJJJ9
9(amp -amp-7$+++-9(( amp( ampamp0-1CAAC9
(8ltlt9+(+9ltampamplt amp$ltamp09 MBGB=++ADBA7CAAJgt9
$7amp amp7amp amp-913amp )amp amp(amp0$7amp8
$amp$-amp+ amp97CAAG9
-7 amp7amp-amp9( ( amp(amp0+8-$ampamp++7
CAAF9
Building Science Corporation GF wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
1313
13
13 1313
13
131313 1313
Building Science Corporation $ wwwbuildingsciencecom
30 Forest St Somerville MA 02143
E Works Cited
9ADF8+amp+ 81$$=-amp-7gt9( amp00CAAI9
(8ltlt9-$amp+amp9lt-amp+lt(+lt+(ADF+amp+ 1$$
-amp-lt+ampC +1$$ -+lt+ M KCA -+9
(amp77amp - 9 2ampamp++
+amp$-$amp+913ampamp)327307CAAD9
9$$-+amp+ amp913ampamp 0CAAH9
(8ltlt9 9lt+ LL+ampL$19+(09
+amp77amp +amp19+amp$()-$$amp$900 ) $
0BJJF9
- amp79FA9amp($+(($amp amp+-$13+amp1$$9( amp7BJGE9
+amp17 amp7- 7 $$( $+7amp1213 -amp9 $$amp$
amp$-+8$amp+amp-ampampamp$$ $ampampamp
$$$+9( amp07CAAH9
+-79((0131D7CAAH9 (8ltlt91--9lt M D(A5-M ampamp$(
=++13 G7CAAJgt9
279amp+- -ampamp2-$ -+ $amp + -amp$amp+
$2amp9 (((ampampampamp7-( 1+CJ=CAAHgt8DBBDBC9
-++-7139979139amp713997137amp13913913ampampamp913267113$amp5113)
- ampamp amp07amp8amp$+ -amp$amp7CAAI9
3713999amp4(13)( ) $ amp amp
+ amp07amp8amp$+ -amp$amp7CAAG9
(+amp7$$7ampampampamp$9 1+$(+amp13+-$amp+9amp
7DBDCE913+amp7 8+-+17BJJJ9
9(amp -amp-7$+++-9(( amp( ampamp0-1CAAC9
(8ltlt9+(+9ltampamplt amp$ltamp09 MBGB=++ADBA7CAAJgt9
$7amp amp7amp amp-913amp )amp amp(amp0$7amp8
$amp$-amp+ amp97CAAG9
-7 amp7amp-amp9( ( amp(amp0+8-$ampamp++7
CAAF9
Building Science Corporation GF wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
E Works Cited
9ADF8+amp+ 81$$=-amp-7gt9( amp00CAAI9
(8ltlt9-$amp+amp9lt-amp+lt(+lt+(ADF+amp+ 1$$
-amp-lt+ampC +1$$ -+lt+ M KCA -+9
(amp77amp - 9 2ampamp++
+amp$-$amp+913ampamp)327307CAAD9
9$$-+amp+ amp913ampamp 0CAAH9
(8ltlt9 9lt+ LL+ampL$19+(09
+amp77amp +amp19+amp$()-$$amp$900 ) $
0BJJF9
- amp79FA9amp($+(($amp amp+-$13+amp1$$9( amp7BJGE9
+amp17 amp7- 7 $$( $+7amp1213 -amp9 $$amp$
amp$-+8$amp+amp-ampampamp$$ $ampampamp
$$$+9( amp07CAAH9
+-79((0131D7CAAH9 (8ltlt91--9lt M D(A5-M ampamp$(
=++13 G7CAAJgt9
279amp+- -ampamp2-$ -+ $amp + -amp$amp+
$2amp9 (((ampampampamp7-( 1+CJ=CAAHgt8DBBDBC9
-++-7139979139amp713997137amp13913913ampampamp913267113$amp5113)
- ampamp amp07amp8amp$+ -amp$amp7CAAI9
3713999amp4(13)( ) $ amp amp
+ amp07amp8amp$+ -amp$amp7CAAG9
(+amp7$$7ampampampamp$9 1+$(+amp13+-$amp+9amp
7DBDCE913+amp7 8+-+17BJJJ9
9(amp -amp-7$+++-9(( amp( ampamp0-1CAAC9
(8ltlt9+(+9ltampamplt amp$ltamp09 MBGB=++ADBA7CAAJgt9
$7amp amp7amp amp-913amp )amp amp(amp0$7amp8
$amp$-amp+ amp97CAAG9
-7 amp7amp-amp9( ( amp(amp0+8-$ampamp++7
CAAF9
Building Science Corporation GF wwwbuildingsciencecom
30 Forest St Somerville MA 02143
Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document
Building America Special Research Project High-R Walls Case Study Analysis
About this Report This report was prepared with the cooperation of the US Department of Energyrsquos Building America Program
Direct all correspondence to Building Science Corporation 30 Forest Street Somerville MA 02143
Limits of Liability and Disclaimer of Warranty
Building Science documents are intended for professionals The author and the publisher of this article have used their best efforts to provide accurate and authoritative information in regard to the subject matter covered The author and publisher make no warranty of any kind expressed or implied with regard to the information contained in this article
The information presented in this article must be used with care by professionals who understand the implications of what they are doing If professional advice or other expert assistance is required the services of a competent professional shall be sought The author and publisher shall not be liable in the event of incidental or consequential damages in connection with or arising from the use of the information contained within this Building Science document