irc chapter 11 and hers residential energy kelly parker, p.e. oklahoma building summit august 26,...

IRC CHAPTER 11 AND HERSRESIDENTIAL ENERGY

Kelly Parker, P.E.Oklahoma Building Summit

August 26, 2015

http://www.oshba.org/

IRC Chapter 11 and HERS

HERS: Home Energy Rating System

IRC Chapter 11 and HERS

RESNET

The RESNET vision: “RESNET’s vision is of a world that encourages and rewards minimum building energy use through independent, performance-based building certification.”

RESNET

The RESNET mission: “RESNET’s mission is to ensure the success of the building energy performance certification industry, set the standards of quality and increase the opportunity for ownership of high performance buildings.”

Who Recognizes RESNET’s Standards

Builders (for the HERS Rating)Contractors (the emerging retrofit market)States and municipalities for code complianceFederal government agencies

IRS: 2005 EPACT new housing tax credit Environmental Protection Agency (EPA): the

ENERGY STAR for Homes program (Version 3) Department of Energy (DOE): Building America

and National Builders Challenge programs

2009 International Residential Code

Chapter 11

• Approved software is used to develop a Index.

• REM/Rate • Energy Gauge • Others

IRC CHAPTER 11 AND HERS

HERS inputs into REM/Rate:1. General building inputs (sf, vol, # of floors, bedrooms)

2. Foundation wall properties

3. Slab floor properties (sf, insulation, exposed perimeter)

4. Floors over unconditioned space.

5. Rim and band properties (sf, R-value)

6. Above grade wall properties (sf, type)

7. Windows and glass doors (sf, U-factor, SHGC, shading)

8. Door properties

9. Ceiling properties (sf, type, R-value)

Chapter 11 and HERS

HERS inputs into REM/Rate:10.Mechanical equipment properties (Btuh, efficiency)

11. Duct system summary (sf, R-value, location, leakage)

12.Blower door test (leakage)

13.Mechanical ventilation

14.Appliances and lighting summary

IRC 2009 RESIDENTIAL ENERGY

• New Codes are here and adopted statewide July, 2011.

• The 2009 IRC addresses issues that have been building problems in the past.

• Several problem areas that have been around for years will now have solutions.

Adopted Building Codes

Code Adopted Effective Date of Adoption Modifications to the code

International Residential Code ®, 2009 Edition (IRC®, 2009) July 15, 2011 Click Here for modifications to

the code adopted by reference

Adopted Building Codes

Code Adopted Effective Date of Adoption Modifications to the code

International Residential Code ®, 2009 Edition (IRC®, 2009) July 15, 2011 Click Here for modifications to

the code adopted by reference

Oklahoma Uniform Building Code Commission

www.ok.gov.oubcc/

http://www.ok.gov/oubcc/documents/Permmanent%20Rules%20-%20IRC%202009.pdf




Chapter 11, Energy Efficiency

N1101.1 Scope

This chapter is for regulating the design and construction of buildings to improve the energy efficiency of those structures.


N1101.2 Compliance

• Demonstrated by either meeting the requirements of this chapter or the 2009 International Energy Conservation Code.

• Requirements are climate specific according to Figures N1101.2 and Table N1101.2.


N1101.2.1 and Table N1101.2

Climate Zones, Moisture Regimes, and Warm-Humid Designations (clarification)

• Places all the above info into one table.

• Provides county designations for clarity and usability.

• Warm humid counties are now indicated with an asterisk.

All counties in Oklahoma are Climate Zone 3A except for Beaver, Cimarron, and Texas located in the panhandle

which are 4B


By accepting State Energy Program funding and submitting letters assuring the

Department of Energy that their states would comply with the terms of Section 410, all 50

states have committed to do three things:

1. Adopt a residential building energy code that meets or exceeds the 2009

International Energy Conservation Code (IECC);¹

2. Adopt a commercial building energy code that meets or exceeds the

ANSI/American Society of Heating, Refrigerating and Air-Conditioning Engineers

(ASHRAE)/IESNA Standard 90.1-2007; and

3. Develop and implement a plan, including active training and enforcement

provisions, to achieve 90 percent compliance with the target codes by 2017,

including measuring current compliance each year.

¹ U.S. DOE has determined that the 2009 International Residential Code (IRC) does not

meet the energy provisions of the 2009 International Energy Conservation Code (IECC).


N1101.3 Identification

The code is to identify materials, systems and equipment that allow for the determination of compliance to meet the energy efficiency requirements of this chapter.

All counties are in zone 3AExcept Beaver, Cimarron, and Texas, which are in zone 4B.



N1101.4 Building Thermal Envelope Insulation

• All installed insulation ≥12” must have the R-value marked or a certificate must be provided.

• For sprayed or blown insulation (fiberglass or cellulose), a certificate must list:– Initial installed thickness– Settled thickness– Settled R-value – Installed density– Coverage area– Number of bags installed


N1101.4 Building Thermal Envelope Insulation (continued)

For sprayed polyurethane

foam:• Installed thickness• R-value of installation

Sticker shall be signed, dated and posted in a “conspicuous location on the job site.”


N1101.4 Blown or Sprayed Roof/Ceiling Insulation

• Markers installed 1 for every 300sf with numbers at least 1” tall to help determine the depth of the installed insulation.

• Stickers must face the attic access opening.


N1101.5 Fenestration Product Rating

• For U-factors (windows, doors and skylights) and solar heat gain coefficient (SHGC) (glazed fenestration) must have a label on each product or assigned a default value from Tables N1101.5(1)-N1101.5(3).

• Must be accredited by an independent lab and labeled and certified by the manufacturer.

N1101.8 Above Code Programs

• National, state, or local energy efficiency programs may be used, at the building official or other jurisdiction’s discretion as conforming to the energy code.

• REM/Rate and HERS Index

• REScheck



N1101.9 Permanent Energy Certificate (modification)

• Certificate shall not cover or obstruct required labels on an electrical distribution panel. (Sticker not required in Oklahoma)

• An efficiency shall not be listed for gas-fired unvented room heaters, electric furnaces, or electric baseboard heaters.


Coming to ALL Houses

Example


N1102.1 Insulation and Fenestration Criteria

The building envelope shall meet the requirements found in Table N1102.1 according to climate zones found in Table N1101.2.


N1102.1.1 R-value Computation

• Shall be the sum of the wall insulation R-value plus the exterior sheathing. No other components are included.

• The settled R-value shall be used for blown insulation.


N1102.1.2 U-factor Alternative

1. U-factor from Table N1102.1.2 shall be allowed instead of the R-values from Table N1102.1.

2. Comment: U-factor is the inverse of the R-value. Ceiling U-factor of 0.033 is equal to an R-value of 30.

U=1/R


N1102.1.3 Total UA Alternative

“If the total building thermal envelope UA (sum of the U-factor times assembly area) is less than or equal to the total UA resulting from using the U-factors in Table N1102.1.2, (multiplied by the same assembly area as in the proposed building), the building shall be considered in compliance with Table N1102.1.”


N1102.2.1 Ceilings with Attic Spaces

Section requires increased R-values over the exterior wall top plates:

• R-30 where R-38 is called for in attic.• R-38 where R-49 is called for in attic.• Does not address R-30 insulation requirement. • The stated insulation must be uncompressed.

Comment: An R-30 batt in a 6” cavity is approximately equal to an R-21.


N1102.2.2 Ceilings without Attic Spaces

Where >R-30 is required for a ceiling but space does not allow for it, R-30 shall be allowed for up to 500sf.


N1102.2 Ceiling and Access Hatch Insulation Requirements (clarification)

• Access doors to unconditioned space will be weatherstripped and insulated to same R-value as the ceiling.

• Insulation baffle installed at edges to prevent spilling into the living space and maintain the installed R-value.


Table N1102.2.5 Steel Framed Wall Insulation (modification)

Contains an option for steel framed wall without cavity insulation for Zones 1 thru 4. Apply continuous insulation R-10 to outside (equivalent of wood frame R-13).


N1102.2.6 Floors• Floor insulation must be placed in permanent contact

with the subfloor.• Comment: Staples are not permanent; gravity eventually

wins. Requires tension wires or equivalent.


N1102.2.7 Basement Walls

• Basement walls for conditioned space shall be insulated from the grade plane to either 10 feet below or to the basement floor, whichever is less.

• For climate zone 3, requires either an R-5 on the exterior or R-13 on the interior.

• No wall insulation required if the floor above the basement is insulated.


N1102.2.8 Slab-on-grade Floors

• No insulation required for Climate Zone 3.• Comment: Slab insulation can be used for the

Federal Tax Credit, which expired December 31. We are hoping it will be renewed.

• Comment: Some builders are achieving a HERS Index of 70 (30% more efficient than a house built to the 2004 IECC) and less to obtain the state tax credit.


N1102.2.9 Crawl Space Walls

• Nothing required if floor is insulated and crawl is vented.

• If unvented, crawl space wall insulation must be permanently attached from the floor to the finished Grade level and then vertically and/or horizontally an additional 24 inches.

• Exposed earth shall be covered with a Class I vapor retarder, overlapped 6” and joints sealed or taped and attached to the stem wall at a height of at least 6”.


N1102.2.11 Thermal Isolated Sunroom Insulation

• Ceiling insulation shall be R-19 for Climate Zones 1-4 and R-24 for Zones 5-8.

• Wall insulation shall be at least an R-13.

• New walls to meet current construction code requirements.


N1102.3.3 Glazed Fenestration Exemption

U-factor and SHGC requirements can be waived for up to 15sf of glass.

N1102.3.4 Opaque Door Exemption

For one opaque door up to 24sf can be exempted from the U-factor requirements.


N1102.3.6 Replacement Fenestration

Shall meet the requirements for U-factor and SHGC from Table N1102.1.


N1102.4.1 Sealing of the Building Thermal Envelope (clarification)1. Joints, seams and penetrations

2. Site-built windows, doors, and skylights

3. Openings between windows/doors and framing or jambs

4. Utility penetrations

5. Dropped ceilings or chases

6. Kneewalls

7. Walls and ceilings separating garage from conditioned space

8. Behind tubs and showers on exterior walls

9. Common walls between units

10. Attic access openings

11. Rim joist junction

12. Other sources of infiltration


N1102.4.2.1• Envelope leakage testing

option to 7 ACH at 50 Pa. Seven requirements for testing.

N1102.4.2.2• Visual inspection option

allowed by code official by third party independent from the insulation contractor following list in N1102.4.1.


N1102.4.5 Recessed Lighting (modification)

• Shall be IC rated.

• Shall be labeled as meeting ASTM E 283 for air leakage.

• Shall be sealed with caulk or a gasket between the housing and interior wall.

• New term: ICAT, Insulation Contact Air Tight


N1103.1.1 Programmable Thermostat

• Each dwelling unit shall have one thermostat capable of maintaining a daily schedule to maintain different temperature set points.

• Must be able to achieve temperatures from 55° to 85°.

• Not required in Oklahoma at this time. Update: July, 2015 new IRC??


N1103.1.2 Heat Pump Supplementary Heat

When supplementary electric resistance heat, must have controls preventing supplemental heat operation when the unit is capable of meeting the heating load.

Emergency Heating


N1103.2.1 Duct Insulation

Ducts in unconditioned space shall be R-8. All others shall be R-6.

Oklahoma Tax Credit: Supply and return ducts shall be insulated to a minimum of R-8


N1103.2.2 Duct Sealing (addition)

• Duct tightness shall be verified by either

– Post construction test, leakage to outside at 8 cfm per 100 sf or total leakage test at 12 cfm per 100 sf, both at 25 Pa.

– Rough-in test, total leakage at 6 cfm per 100 sf tested at 25 Pa.

(Visual inspection may be used instead of the rough-in test and post construction

test in Oklahoma.)


N1103.2.3 Building Cavities

Building framing cavities shall not be used as supply ducts

N1103.3 Mechanical System Piping Insulation

All mechanical system piping carrying fluids above 105°F or below 55°F must be insulated to at least an R-3.


N1103.4 Circulating Hot Water Systems

• All lines shall be insulated to at least an R-2.

• In addition, there must be a readily accessible manual switch for disengaging the system when not being used.


N1103.6 Equipment Sizing• “Heating and cooling equipment shall be sized as specified in

Section M1401.3.”• All buildings must have load calculations performed.

M1401.3 Sizing

HVAC system sized according to ACCA Manual S based on load calculations from ACCA Manual J (Version 8 is the latest version)

Comment: ACCA Manual S - Residential Heating and Cooling Equipment Selection

Comment: ACCA Manual J8 – Residential Load Calculation


N1103.8.1 Pool Heaters

• All pool heaters shall have a readily accessible on/off switch for turning the equipment off without adjusting the thermostat.

• No continuous burning pilot lights allowed.


N1103.8.2 Time Switches

Heaters and pumps must have time switches installed that can automatically control use of those components.


N1103.8.3 Pool Covers

• Heated pools shall have a vapor retardant pool cover on or at the water surface. Comment: removed from the code for Oklahoma.

• Pools heated above 90°F must have a cover with an R-value of at least 12. Comment: remains in the Oklahoma code.


N1104 Lighting Systems (addition)

• 50% of permanently installed lighting fixtures required to be CFLs or other high-efficacy lamps.

• Comment: Can or

recessed lighting are

exempt in Oklahoma.• Update, 2015 IRC??

Thank You for Your Time

Kelly Parker, P.E. [email protected]

405-946-0206

mailto:[email protected]

http://www.oshba.org/

irc chapter 11 and hers residential energy kelly parker, p.e. oklahoma building summit august 26,...

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