DS 418:2011

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DS 418 Translation:

VIA UNIVERSITY COLLEGE Jens Peder Pedersen

DS 418:2011

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København DS projekt: M251829 ICS: 91.120.10 First part of this publication's designation is: DS, which means that it is a standard prepared at a national level.

The DS publication is in Danish. This publication replaces: DS 418:2002, DS 418/Till. 2:2008, DS 418/Ret.1:2003 and DS 418/Till.1:2005. DS – publication types Danish Standard publishes different publication types. The type on this publication is clear from the front page. There may be the issue: Danish standard

• standard, which has been drawn up at a national level, or that has been based on another country's na-tional standard, or

• standard, which has been prepared at an international and/or a European level, and that just got status as Danish standard

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to status as standard, e.g. a technical report, or • European prestandard

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DS leaflet • publication with informative material

For these publication types with informative material can furthermore be published

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DS designation All DS-publications' designation starts with DS followed by one or more prefixes and a no., e.g. DS 383, DS/EN 5414 etc. If a no. is followed an A or Cor, it means, either that it is a supplement or a correction magazine to the main standard, or that it has been imported in the main standard. DS designation is indicated on the front page. Agreement with other publication: Agreement may either be IDT, EQV, NEQ or MOD

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standard, but prepared on a basis of the this. • MOD: When the publication has been modified in relation to a given publication.

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Table of content 0 Preface ................................................................................................................................................................. 6 1   Introduction ............................................................................................................................................................ 7 

1.1 Definitions ..................................................................................................................................................... 7 1.2  Symbols and units ....................................................................................................................................... 10 

2   Design temperatures ............................................................................................................................................ 12 2.1   Design indoor temperature ......................................................................................................................... 12 2.2   Design outdoor temperature ........................................................................................................................ 12 2.3  Other design temperatures .......................................................................................................................... 13 

3   Calculation of transmission loss ........................................................................................................................... 14 3.1   Transmission loss through external walls, roofs, windows and external doors ........................................... 14 3.2   Transmission loss through ground supported floors, basement floors and basement walls ....................... 14 3.3   Transmission loss through partition walls and storey partitions and basements slabs ............................... 14 3.4   Transmission loss through joints around windows and doors ..................................................................... 14 3.5   Transmission loss through foundations under external walls ...................................................................... 14 3.6   Calculation of transmission areas ................................................................................................................ 15 3.7   Calculation of the length of the linear cold bridge ...................................................................................... 17 

4   Calculation of ventilation loss .............................................................................................................................. 19 4.1   Ventilation loss ............................................................................................................................................ 19 4.2   Natural ventilation ........................................................................................................................................ 19 4.3   Mechanical extraction .................................................................................................................................. 19 4.4   Other mechanical ventilation systems ........................................................................................................ 20 

5   Calculation of the total heat loss ......................................................................................................................... 22 5.1   The heat loss for a room and for a building ................................................................................................ 22 5.2   Calculation of transmission loss ................................................................................................................. 22 

6   Calculation of transmission coefficient ................................................................................................................ 23 6.1   Transmission coefficient and heat flow resistance ..................................................................................... 23 6.2   Surface heat flow resistance ....................................................................................................................... 23 6.3   Heat flow resistance for a material layer .................................................................................................... 23 6.4   Heat flow resistance for air filled cavities ................................................................................................... 24 

6.4.1   Non-ventilated cavities......................................................................................................................... 24 6.4.2   Slightly ventilated cavities ................................................................................................................... 25 6.4.3   Ventilated cavities ............................................................................................................................... 25 6.4.4 Not ventilated cavities with reflective surfaces ....................................................................................... 25 

6.5   Ventilated attics ........................................................................................................................................... 25 6.6   Constructions with inhomogeneous material layers ................................................................................... 26 6.7   Constructions with cold bridges .................................................................................................................. 26 

6.7.1  Brick ties .............................................................................................................................................. 27 6.7.2  Pillars and ribs ..................................................................................................................................... 27 6.7.4 Steel plate profiles in steel frame walls ............................................................................................ 29 6.7.5 Foundations under partitioning wall ................................................................................................... 29 6.7.6 Other penetrations ............................................................................................................................. 30 

6.8   Windows, external doors etc. ...................................................................................................................... 32 6.8.1  Calculation of U-value.......................................................................................................................... 32 6.8.2   Other methods for determination of transmission coefficients ............................................................ 35 6.8.3  Other figures and tables for determination of U .................................................................................. 36 

6.9   Ground supported floors, basement floors and basement walls against soil ............................................ 37 6.10   Concrete sandwich elements ...................................................................................................................... 38 6.11   Wedged insulation – Calculation of U-value ............................................................................................... 38 6.12   Joints around windows and doors .............................................................................................................. 40 

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6.12.1 Linear loss Ψs in W/mK for joints around windows and doors in cavity walls ..................................... 40 

6.12.2 The The linear loss Ψsa for the joint around windows and doors in insulated timber frame walls with

lightweight cladding or with brick work front wall. .............................................................................................. 43 6.12.3 The linear loss Ψsa for the joint around windows and doors in front of metal frames in insulated

frame walls with light weight cladding or with a brick work front wall. .............................................................. 43 6.12.4 The linear loss Ψs for joints around roof light and skylight including connecting panels and frame. .. 44 

6.13   Foundations ................................................................................................................................................. 45 6.13.1 Foundations for external walls at ground supported floors ................................................................. 45 6.13.2 Linear loss coefficients for foundations below doors and windows ...................................................... 52 6.13.3 Basement outer wall foundations ...................................................................................................... 55 

6.14 Thermal bridges at corners .............................................................................................................................. 56 7   Heat flow resistance and thermal conductivity of materials ................................................................................ 57 

7.1   Introduction .................................................................................................................................................. 57 7.2   Basis for determination of heat flow resistance and thermal conductivity ................................................... 57 

7.2.1   Declared values .................................................................................................................................. 57 7.2.2   Design values ...................................................................................................................................... 57 7.2.3   Special provisions ............................................................................................................................... 58 

Annex A ....................................................................................................................................................................... 59 (normative) ................................................................................................................................................................... 59 Correction of transmissions coefficients ..................................................................................................................... 59 

A.1   General ........................................................................................................................................................ 59 A.2   Correction for air-cracks in the insulation layer .......................................................................................... 59 

A.2.1  Air-cracks across the insulation layer ................................................................................................. 59 A.2.2  Air circulation on the warm side of the insulation............................................................................... 60 A.2.3  Examples ............................................................................................................................................. 60 

A.3   Correction for ties ........................................................................................................................................ 60 A.4   Correction for rain on “upside down” roof .................................................................................................. 61 

A.4.1 Generally .............................................................................................................................................. 61 A.4.2  Correction of the roof construction’s transmission coefficient for the rain amount, that runs be- ....... 62 tween the insulation and the watertight membrane ............................................................................................. 62 

Annex B ....................................................................................................................................................................... 63 (normative) ................................................................................................................................................................... 63 Determination of linear loss for thermal bridges in constructions ................................................................................ 63 Annex C ....................................................................................................................................................................... 64 (normative) ................................................................................................................................................................... 64 Determination of linear loss for connections around windows and doors ................................................................... 64 

C1  Windows and doors in the façade mounted in straight groove .................................................................. 64 C.2   Windows and doors in the front mounted in a displaced groove ................................................................. 64 C.3  Windows and doors at foundation ............................................................................................................... 66 C.4   Skylights and roof windows ......................................................................................................................... 67 

Annex D ....................................................................................................................................................................... 70 (normative) ................................................................................................................................................................... 70 Determination of linear loss for outer wall foundations ............................................................................................... 70 

D.1   Linear loss for outer wall foundations at terrain deck .................................................................................. 70 D.1.1  Over all two-dimensional heat flow ...................................................................................................... 71 D.1.2  One-dimensional heat flow through outer wall and terrain deck ......................................................... 72 

D.2  Linear loss at foundations below doors and windows at terrain deck ........................................................ 73 D.3   Linear loss for the basement outer wall foundations ................................................................................... 75 

Annex E ....................................................................................................................................................................... 77 (normative) ................................................................................................................................................................... 77 

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Control demands for not CE-marked heat insulation products ................................................................................... 77 Annex F ....................................................................................................................................................................... 79 (normative) ................................................................................................................................................................... 79 Design values for brick, concrete and other building materials ................................................................................... 79 Annex G ....................................................................................................................................................................... 86 (informative) ................................................................................................................................................................. 86 Design values for calculation of existing constructions in connection with rebuilding and renovation ..................... 86 Annex H ....................................................................................................................................................................... 87 (informative) ................................................................................................................................................................. 87 Detailed calculation procedure for the overall U-value for skylights ............................................................................ 87 Annex I ......................................................................................................................................................................... 89 (informative) ................................................................................................................................................................. 89 Calculation example – Existing building with window with two layer energy pane ..................................................... 89 Annex J ........................................................................................................................................................................ 90 (informative) ................................................................................................................................................................. 90 Concrete sandwich elements – Calculation example .................................................................................................. 90 Annex K ....................................................................................................................................................................... 93 (informative) ................................................................................................................................................................. 93 Standards and proposals for standards, referring to DS 418 ...................................................................................... 93 Annex L ........................................................................................................................................................................ 95 (informative) ................................................................................................................................................................. 95 Calculation example – DS 418 .................................................................................................................................... 95 

L.1  Transmission areas and length of linear loss .............................................................................................. 97 L.2  Transmission coefficients ............................................................................................................................ 98 

L2.1  Outer wall ............................................................................................................................................. 98 L.2.2  Connections around windows and doors........................................................................................... 100 L.2.3  Windows and doors ........................................................................................................................... 100 L.2.4  Terrain deck ....................................................................................................................................... 101 L2.5  Foundation ......................................................................................................................................... 102 L2.6  Ceiling and roof .................................................................................................................................. 102 L2.7  Light shafts in connection with roof windows .................................................................................... 103 L.2.8  Connections around roof windows .................................................................................................... 103 L.2.9  Linear loss at connections ................................................................................................................. 103 

L.3  Heat loss .................................................................................................................................................... 105 Annex M ..................................................................................................................................................................... 106 (normative) ................................................................................................................................................................. 106 Thermal bridges at corners ........................................................................................................................................ 106 

M.1  Vertical outer wall connections .................................................................................................................. 106 M.1.1   Generally ........................................................................................................................................... 106 M.1.2   Right-angeled corners ....................................................................................................................... 106 M.1.3  Non-right-angeled corners ................................................................................................................. 108 

M.2  Wall – roof connection ............................................................................................................................... 110 M.2.1  Outer wall and horizontal ceiling ........................................................................................................ 110 M.2.2  Sloping ceiling and outer wall ............................................................................................................ 112 

M.3  Battlement .................................................................................................................................................. 113 M.4  Vertical apartment division/ceiling ............................................................................................................. 114 M.5  Example ..................................................................................................................................................... 115 M.6   Geometry and thermal conductivity ........................................................................................................... 116 

Annex N ..................................................................................................................................................................... 117 (informative) ............................................................................................................................................................... 117 Determination of the transmission coefficient Ug for panes in existing buildings ...................................................... 117 

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0 Preface This 7. edition of DS 418 replaces DS 418, 6. edition, 2002 with supplements to match 1 (DS 418/Till. 1: 2005) and supplements 2 (DS 418/Till.2:2008). DS 418 is a part of the Danish building legislation (the building regulations) and stands over the European and in-ternational standards as such, except where have been referred to these standards. 0.1 The regulations' coming into effect 7. edition will come into effect on June 17th 2011. 0.2 Temporary provisions In the period June 17th - December 17th 2011 projects can be done either after the 6th edition of DS 418:2002 as well as supplements 1 and 2 or after the 7th edition version. After December 17th 2011 it is only 7. edition that is valid. 0.3 Normative references Below have been mentioned standards that have been referred to in DS 418. It is just those parts of the standards that we refer to, that are normative. In annex K the standards' title has been stated.

DS 469 DS/EN 13162 DS/EN 673 DS/EN 13163 DS/EN 823 DS/EN 13164 DS/EN 1520 DS/EN 13165 DS/EN 1745 DS/EN 13166 DS/EN 1873 DS/EN 13167 DS/EN 12412-2 DS/EN 13168 DS/EN 14351-1 DS/EN 13169 DS/EN 14963 DS/EN 13170 DS/EN ISO 8990 DS/EN 13171 DS/EN ISO 6946 DS/EN 13172 DS/EN ISO 7345 DS/EN 14063-1 DS/EN ISO 9251 prEN 14063-2 DS/EN ISO 9288 DS/EN 14064-1 DS/EN ISO 10077-1 DS/EN 14064-2 DS/EN ISO 10077-2 DS/EN ISO 10211 DS/EN ISO 10456 DS/EN ISO 12567-1 DS/EN ISO 12567-2 DS/EN ISO 13789 DS/EN ISO 14683 DS/ISO 16269-6

In annex K have also been stated a list of other standards and proposals for standards that have relevance for cal-culation of buildings' heat loss.

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1 Introduction The calculation rules are aiming to obtaining conformity when estimating the heat flow resistance and the heat loss of buildings under Danish climate conditions, among other things regarding the energy requirements of the Building Regulation (BR). It is the users responsibility, that the requirements of the BR are met. There can occur table values in DS418, which doesn’t meet these requirements. These values can only be used in connection with existing constructions. The rules provide instructions on how to calculate building components transmission coefficient U for estimation of the components thermal insulation ability. U-values are based on the design of specific constructions and values for products cannot be used immediately by calculation of heat loss. It is provided that constructions and combined components are correct build, by using approved methods and correct workmanship. A construction which as whole lacks windproofness or which allows unintended ventilation or convection in or around the heat insulation layers can have a considerably lesser insulation ability the calculat-ed. Normal windproofness and dampproofness are provided. In accordance with chapter 6.8 is it also possible to estimate the U-value for windows and doors, by measuring on the specific windows used in a construction. Material values determined by average conditions in the construc-tions, are used in the calculations. Due to simplifications can the calculation rules not be used for detailed calcu-lations e.g. surface temperature, condensation or damp flow. The calculation rules indicate a method for calculating a rooms or buildings design heat loss. The method is de-signed so the design heat loss approximately is equal to the rooms or the buildings actual heat loss under sta-tionary conditions by the indicated internal and external climate conditions. By calculating the design heat loss of a room, situations where adjacent rooms temporarily are unheated, are not considered. For a simplified method for dimensioning of radiators refer to DS 469. In specific cases where it can be proven that the calculation method will not yield a reasonable approximation to the actual conditions, more detailed methods must be used. The rules are elaborated thus that the calculations become fairly simple and practically useable. The user of DS418 must have sufficient technical knowledge. Special situations may be encountered, where the rules are not fully covering. In any case it should be appraised if the actual situation is covered by the rules or not. Deviation from these rules is permitted, if it is documented that the deviation is appropriate and based on technical ground. Such documentation must be carried out according to the EN and ISO standards, if not this standard prescribes otherwise. By interpretation questions refer to Dansk Standard, Kollegievej 6, 2920 Charlottenlund tlf. 39 69 61 01 or ds@ds.dk 1.1 Definitions 1.1.1 Declared value for Heat flow resistance and thermal conductivity The value of a building-materials ability Heat flow resistance or thermal conductivity based up on measure-ments, at reference temperature and humidity. Regarding definition see DS/EN ISO 10456 item 3.1.1 1.1.2 Density The density of a material is its weight divided by volume, where the volume includes the pores and cavities of the material. The density applied is the one for the material in dry conditions. It should be considered, however, that this density in some cases might be different from the nominal density of the material according to normal product names etc. (Regarding definition see DS/EN ISO 9251 item 3.7).

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1.1.3 The design value for thermal conductivity and heat flow resistance The design value for a building-materials thermal conductivity or heat flow resistance under specific conditions, which are considered being typical for the materials thermal properties, when used in a building-component. Regarding definition see DS/EN ISO 6946 item 5.1. 1.1.4 The design room temperature The design room temperature is a theoretical temperature, which is determined only as the basis for estimating the design heat loss of the applicable room. The room temperature represents the combined value of air tempera-ture and radiation temperature, which may result in equal heat distribution to the surrounding space limits of the applicable room. For living rooms and alike the room temperature and the operative temperature in the middle of the room practically will have the same value. Regarding definition see DS/EN ISO 10211-1 item 3.1.17 1.1.5 The design outdoor temperature The design outdoor temperature is the theoretical temperature, determined for the calculation of the design heat loss. It does not include the extreme impact of climate encountered, but a certain limit frequency. Regarding definition see DS/EN ISO 10211-1 item 3.1.16 1.1.6 The design heat loss The design heat loss for a certain room or a building is equal to the heat effect to be provided in order to maintain the design room temperature at the determined outdoor temperature conditions. The design heat loss comprises transmission heat loss and ventilation heat loss. 1.1.7 Energy frame The energy frame is the maximum annual permissible heat requirement for heating of rooms and ventilation ac-cording the building regulations. 1.1.8 Displaced rabbet Method for the in-building of windows in the outer wall. Against the background of traditional mounting in a straight rabbet is managed typically both a smaller heat loss through the window and a line loss in the connection as well as advantages concerning solar heating- and light incidence, architecture, fastening and jointing. 1.1.9 Heat flow resistance The heat flow resistance is the relation between temperature difference and heat flow density. The heat flow re-sistance is describing the resistance towards heat transmission through 1 m2 of the applicable area or the appli-cable building material. Regarding definition see DS/EN ISO 7345 item 2.7 1.1.10 Cold bridge Cold bridge is the part of the construction with significant smaller heat flow resistance than the rest of the con-struction. Regarding definition see DS/EN ISO 10211-1 item 3.1.1 1.1.11 Linear cold bridge A linear cold bridge is a cold bridge with little width, which impact on the heat loss is depending on the length of the cold bridge and the two-dimensional heat flows, it may cause. Regarding definition see DS/EN ISO 10211 item 3.1.2 1.1.12 Linear heat loss (The linear transmission coefficient) The heat loss through a linear cold bridge. The linear heat loss is the difference between the one-dimensional and the two-dimensional heat flow.

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1.1.13 Normal emission The normal emission for surface is the relation between the radiation in a direction perpendicular to the surface and the equivalent radiation from an absolute black surface with same conditions and temperature. The normal emission thus is an expression of the relative radiation exchange with the surroundings. Regarding definition see DS/EN ISO 9288 item 5.8. 1.1.14 Operative temperature The operative temperature represents the combined value of air temperature and radiation temperature, which would result in equal heat contribution through conviction and radiation from the person, as the real/actual tem-peratures would give. 1.1.15 Point cold bridge The point cold bridge is a cold bridge of little extent, of which the impact on the heat loss is depending on the three-dimensional heat flows it may cause. Regarding definition see DS/EN ISO 14683 item 3.1.2 1.1.16 Thermal coupling coefficient (Lf) Heat flow (per degree temperature difference) between two surroundings that are in thermal contact with the building component or construction that is considered. 1.1.17 Transmission coefficient, U-value The transmission coefficient for a building component is the relation between the heat flow and the area and difference between the temperatures on each side of the building-component. Regarding definition see DS/EN ISO 7345 item 2.12 1.1.18 Transmission loss The transmission loss is the heat amount, which flows through the rooms or the buildings surrounding space limits, per time unit, because of difference in temperature. 1.1.19 Thermal conductivity The thermal conductivity is the heat flow density divided by the difference in temperature under sta-tionary conditions. Regarding definition see DS/EN ISO 7345 item 2.5 1.1.20 Heat flow density The heat flow density is the heat flow per area unit. Regarding definition see DS/EN ISO 7345 item 2.3 1.1.21 Heat loss frame The heat loss frame is the design transmission loss, which can be estimated for a building with transmission co-efficient as well as windows and door areas according to the building regulations. 1.1.22 Ventilation loss The ventilation loss is the heat amount per time unit, which is required to heat the incoming air in the case of exchange of air through ventilation.

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1.2 Symbols and units Symbol Size SI-unit

d thickness m

l length m

L coupling coefficient Wm/K

b width m

h height m

A area m2

V volume m3

q volume flow m3/s

n air change h-1

ρ density kg/m3

θ Celsius temperature oC

∆θ temperature difference K

Φ heat flow, heat loss W

λ thermal conductivity W/mK

λdeclared declared thermal conductivity W/mK

U the resulting transmission coefficient including corrections W/m2K

U’ the uncorrected transmission coefficient W/m2K

∆U corrections according to annex A W/m2K

R design heat flow resistance m2K/W

Rdeclared declared heat flow resistance m2K/W

Ψ (psi) linear transmission coefficient (linear loss) W/mK

Χ (chi) transmission coefficient for point cold bridge W/K

c heat density, specific heat capacity J/kg K

Indexes

A surrounding (ambient)

E outside (exterior)

F foundation

F frame of window

Ϝ fastening (mechanical)

G glass part of window

G gas layer/air layer (gas(air)space)

H homogeneous layer

I internal

I insulation

j soil

k construction

k cold bridge

l air layer

m material layer

p panel in door (panel) r radiation

r rain

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s surface

s space, gas/air

sa connection

t transmission

T total

v ventilation

Often used SI-prefixes

Prefix multiple of unit

T (tera) 1012

G (giga) 109

M mega) 106

k (kilo) 103

m (milli) 10-3

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2 Design temperatures

Figure 2.1 – Examples of design temperatures

e is the design outdoor temperature i is the design indoor temperature j1 is the soil temperature, where it is equal to outdoor temperature j is the soil temperature, in deeper soil r is the temperature behind radiators g is the floor temperature by floor heating 2.1 Design indoor temperature

The design room temperature θi in residential rooms is normally set to 20ºC. In workrooms the design room temperature is set taking into account the character of the work, which is to be carried out in the rooms. In unheated rooms the temperature can be determined by estimation (qualified guess), but cases of doubt should be recalculated using a heat balance for the room. In front of the heat sources placed near windows, wall parts with reduced insulation; convector pitches and alike higher temperatures should be taken into account. The temperature here is to be set according to the heat plants designed temperature. Normally a temperature here of 50ºC is applied. In rooms using floor heating the temperature in the floor construction at floor level is set equivalent to the design temperature of the floor heating plant. Normally a temperature of 30ºC is to be applied. This temperature is also applied when calculating the heat loss through the foundations near constructions with floor heating. 2.2 Design outdoor temperature

The design outdoor temperature θe usually is set to -12ºC. In special cases the design outdoor tempera-ture can be either increased or reduced.

The design soil temperature θj under heated buildings and in the substrata around the heated buildings is set to 10ºC.

In 0 – 2 meters depth the soil temperature is = j1 = -12ºC.

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2.3 Other design temperatures

The design crawl space temperature for normal sufficiently ventilated crawl space the temperature is set to -5ºC. The temperature in other kinds of crawl spaces should be calculated by using the heat balance of the applicable crawl space. The crawl space ventilation applied in cubic meter per second normally is 0.3 times the total area in square meters of the ventilation openings. The design temperature in open gateways, pas-sages and alike is -12ºC.

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3 Calculation of transmission loss

3.1 Transmission loss through external walls, roofs, windows and external doors

The transmission loss through vertical areas towards outside is estimated using the formula:

φt = U A(θi − θ e )

where

φt is transmission loss in W

U is the transmission coefficient in W/m2K

A is the area of the plane in m2

θi is the design indoor temperature in °C

θe is the design outdoor temperature in °C

The transmission coefficient for different constructions and building components is calculated according to chapter 6, and the area according to chapter 3.6.

3.2 Transmission loss through ground supported floors, basement floors and basement walls

The transmission loss through basement walls being in contact with soil for a depth up to 2 meters is to be estimated using the formula:

φt =U A(θi − θj1)

The transmission loss through ground supported floors and basement floors as well as basement walls in depths more than 2 meters and furthermore basement walls with contact to soil placed underneath the building are to be calculated using the formula:

φt =U A(θi − θj )

where θj is the design soil temperature in °C.

3.3 Transmission loss through partition walls and storey partitions and basements slabs

The transmission loss through partition walls and storey partitions and basement slabs between rooms of different indoor temperature is to be found using the formula:

φt = U A ∆θ

where ∆θ is the difference between the temperature in the adjacent rooms in °C.

The difference in temperature causes heat loss from the warmest room and a heat supplement to the cold-est room.

3.4 Transmission loss through joints around windows and doors

The transmission loss at the joints around windows and doors (cold bridges) is to be estimated using the formula:

where

φt = Ψsa l sa (θi − θ e )

ψsa is the linear loss for the joint in W/m K, referring to chapter 6.12

lsa is the total length of the joint, referring to chapter 3.7

3.5 Transmission loss through foundations under external walls

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DS 418:2011

The transmission loss through external wall foundations surrounding ground supported floors is to be esti-mated using the formula:

φt = ψf lf (θi − θe )

where

ψf is the linear loss for foundations in W/m K according to chapter 6.13

lf is the length of the foundation in m, according to chapter 3.7.

3.6 Calculation of transmission areas

The transmission areas is defined by the outer surface of the outer walls, the bottom surface of the base-ment deck, the top surface of the heat insulation in the ceiling on the upper floor or in the roof, see figure 3.6.1 and figure 3.6.2. For foundations under external walls and under basement walls the transmission area is defined by the upper surface of the floor and by the inner surface of the external walls.

For unheated basement the transmission area of basement decks is measured to the external side of the outer wall, and the transmission area of the outer wall is measured from the underside of the basement deck.

At partition walls that do not make parts of a climate shield, the transmission area is to be calculated to the centerline of the partition wall, and at the storey partition the area is to be calculated to the top surface of the applicable storey partition. For basement walls towards soil the transmission area is defined reaching from the terrain level to the upper side of the basement floor. For basement floors the transmission area is counted to the inner surface of the foundations of the basement walls.

The transmission loss from the upper rooms of a building through the ceiling and roof is normally calculated as a whole, even if there may be an unheated attic in between. The area in this case is equivalent to the transmission area of the ceiling, regardless the roof area being bigger than the ceiling area.

For building parts containing different construction types the transmission area should be calculated individ-ually. Permanent cupboards and closets are normally neglected. Inner doors are normally not taken into account but are regarded as wall areas.

For constructions with bending surface, e.g. bending roof surfaces and bending uoter walls, the transmis-sion area is measured along the bending outer surface. Likewise other attachments for instance skylights, dormers and oriel bay windows the transmission area is counted equivalent to the resulting outer meas-urements. The transmission area of windows and outer doors is equivalent to the free space in the openings. For skylights and sloping windows with free frame sides the transmission area is to be calculated either according to the outer measurements of the skylight or the sloping window or the external surface-area considering the height of the joint see 6.12 and figure 6.12.3. Those areas are also applied when calculating the permissible windows and outer door area according to the building regulation as well as when calculation of the U-value and the permissi-ble area of doors and windows according to the Building regulation.

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DS 418:2011

Building with attic and terrain deck Building with sloping roof and basement

Figure 3.6.1 – Measurements for the estimation of transmission areas. Vertical cross section.

Figure 3.6.2 – Measurements for the estimation of transmission areas for external- and parti-tion walls. (Horizontal section in building).

1. Unheated basement 2. Heated basement

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3.7 Calculation of the length of the linear cold bridge

For the joints around the windows and the doors the length of the cold bridge lsa is defined by the perimeter of the opening, see figure 3.7.1. For joints around skylights and sloping windows with exposed frame sides the length of the cold bridge lsa is defined by the sloping window’s or the skylight’s outer measurement. For outer wall foundations at ground supported floors the length of the cold bridge lf is defined by the outer pe-rimeter of the foundation, see figure 3.7.2. In constructions where the thickness of the insulation vary within the transmission area, or where the insulation is cut off locally within the construction, for instance in front of ribs in cavity walls, the length of the cold bridge lk

is defined by the extend of the varying insulation thickness. Where for instance columns and beams in outer walls or in roofs are cutting off or reducing the insulation, the length of the cold bridge lk is defined by the height of the column or the length of the beam. Where connecting storey partitions and walls and also foundations underneath partition walls cut off or reduce the insulation in the applicable construction, for instance an outer wall, the length of the cold bridge lk is defined by the width of the deck, the height of the wall or the length of the foundation. Cold bridges, where the construction details vary, should be divided into relevant sections regarding the length of the cold bridge.

Figure 3.7.1 - Measurements for the estimation of the length of the linear cold bridges around the window opening in an outer wall, where ribs of bricks are applied beside and over the window opening.

l sa = y2 + x2 + y2

lk = y1 + x1 + ( y1 + y2 + y3) + ( x1 + x2 + x3) + ( y1 + y2 + y3) + x3 + y1

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Figure 3.7.2 – Measurements for the estimation of the length of linear cold bridge for foundations underneath outer walls near ground supported floors. Horizontal section in the top of the founda-tion.

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4 Calculation of ventilation loss 4.1 Ventilation loss

The ventilation loss for a room is calculated by the formula:

v = ρ c q (

i − e )

where

v is the ventilation loss in W

ρ is the density of the air in kg/m3

c is the specific heat of the air in J/kg K q is the volume flow of outdoor air let to the room in m3/s

i is the design room temperature in °C

e is the design outdoor temperature in °C

At 20 °C and 1013 mbar is c = 1005 J/kg K and ρ = 1.205 kg/m3 (dry air).

For normal rooms the difference between air temperature and room temperature is to be neglected. 4.2 Natural ventilation

In buildings where the renewal of air is provided through natural ventilation, the determination of the volume flow q can be based on the amount of fresh air in l/s per m2 heated area. The ventilation loss therefore is:

where

v = ρ c qa

1000 (θ i − θ e ) ≈ 1,21 q A (θ i − θ e )

qa is the fresh air amount in l/s per m2 heated floor area A is the heated floor area in m2.

qa is 0,3 l/s for all ordinary rooms, which means rooms in domestic buildings (living rooms, kithens, wc and bathrooms etc. The term normal rooms comprises in residential buildings (living room, kitchen, toilet and bath rooms etc.) as well as such rooms in other buildings, that could be compared to the above rooms in domestic buildings. In very large rooms – storage rooms and alike – qa could be determined at a lower val-ue for instance 0,18 l/s m2. If leaks through joints at windows and doors are expected to be bigger than normal, causing an exchange of fresh air higher than 0,3 l/s m2 (especially with low outdoor temperatures), the ventilation loss should be estimated taking the length and the permeability of the joints into account respectively for the individual rooms as well as the location of the building. For windows and outer doors which wind proof is not docu-mented in details, an estimated air intake of 0.5 10-3 m3/s should be calculated per m joint between fixed and operable frame for buildings with normal location and 0.8 10-3 per m joint for extraordinary exposed buildings.

4.3 Mechanical extraction

In buildings, where the renewal of air is provided through mechanical ventilation, the ventilation loss is to be calculated on the basis of the exhaust volume flow at normal operation. The ventilation loss is to be distributed to the different rooms of the building according to their volume, re-gardless the number of exhausts from each room.

In case the exhaust air volume equals an exchange of air which is lower than 0,3 l/s m2, the ventilation loss should be calculated as for ordinary rooms with q = 0,3 l/s m2.

The term mechanical exhaust covers ventilation through exhaust systems designed for uninterrupted run-ning. The ventilation loss for rooms supplied with ventilators, only for short term operation, is to be calcu-lated according to chapter 4.2.

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4.4 Other mechanical ventilation systems

In buildings equipped with plants for both mechanical exhaust and mechanical injection, the ventilation loss is to be calculated according to the performance of the plant. It should be taken into account that fresh air will be led to the rooms through infiltration dependent on the difference between the exhaust and injection volume flow through the plant as well as the tightness of the building.

It should be observed that beside the infiltration/exfiltration caused by the ventilation plant covering the difference between the exhaust and injection volume flow through the plant additionally an infiltration and exfiltration will occur, caused by wind and temperature exposure, see figure 4.4.1.

The large square symbolizes the area that is served by the ventilating system, and that can include one or more rooms. Definitions of words “ib” is air inlet “us” is extraction “if” is infiltration, and “xf” is exfiltration. They are equal, if q1 = q2 Normally is q4 = (q2 – q1) + q3 “ul” is outdoor air “ak” is exhaust “vg” is heat recovering “rl” is return air, and “lb” is air conditioning

Figure 4.4.1 Example of mechanical ventilation

The calculation of the ventilation loss depends on the system’s working out. By way of example is in figure 4.4.1 shown a ventilation system, which includes mechanical inlet and extraction as well as heat recovering. If the air isn't moistened, and there aren't included heat pumps in the system, the ventilation loss is decided in the ventilated area by the formula: vc (q2 + q3) (iec (le

Where

q1 is air flow of outdoor air supplied through system in m3/s q2 is air flow of exhaust air in m3/s q3 is air flow of exfiltration in m3/s i is design indoor temperature in oC e is design external temperature in oC

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l is the outdoor air’s temperature after the heat recovering unit in oC C is the density of the air in J/kg K is the specific gravity in kg/m3.

It is provided that all q are measured at same air condition, for instance 20°C and 1013 mbar, and that ρ is re-ferring to those conditions. Furthermore it is provided that the increase of temperature θl - θe of the fresh air led through the ventilation system is caused by the heat recovering only. The temperature θl is to be estimat-ed according to the heat recovering unit’s performance.

The volume flow q1 and q2 are determined according to the ventilation plant performance under normal con-tinuing operation. Normally q1 is a bit less than q2. The exfiltration q3 is determined regarding the tightness and location of the building, where the air tightness of the building envelope is examined by pressure test with 50 Pa (q50), the exfiltration is determined in the useful time in a simple way: 0,04 + 0,06 q50 l/s m2. Outside the

useful time the exfiltration is determined as: 0,06 q50 l/s m2.

The ventilation loss can be covered by the induced heat partly from air handling components, partly from heat sources like radiators, in those rooms where the fresh air is induced.

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5 Calculation of the total heat loss 5.1 The heat loss for a room and for a building

The total heat loss for a building is the sum of the transmission losses of the buildings external surfaces and the ventilation loss for the whole building.

The total heat loss for a building or a part of a building can also be estimated as the sum of all the trans-mission losses of each room.

5.2 Calculation of transmission loss

As part of an estimation of the heat insulation of a building the whole buildings transmission loss can be es-timated without regards to the room division. This method is supplied when comparing the heat loss frame or the energy frame of a building. The calculation in this case is simplified as follows:

- If the different rooms in general are equally heated, it can be neglected that the room temperature in

few rooms for instance the bathroom is different. - However, increased temperature in constructions providing floor heating and also through foundations

near constructions with floor heating, as well as in front of radiators and other heat sources as described in chapter 2.1, should be taken into account.

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6 Calculation of transmission coefficient 6.1 Transmission coefficient and heat flow resistance

The transmission coefficient for a wall, a storey partition, a roof or similar building component is to be esti-mated by the formula:

1′

Where

U´ is the uncorrected transmission coefficient in W/m2 K

Rsi is the surface resistance at the inner surface in m2K/W

Rse is the surface resistance at the outer surface in m2K/W

Ri is the resistance for each material layer in m2K/W

n is the number of layers

The transmissioncoefficient must be corrected regarding cracks in the insulation layer, wall ties and an-chors which penetrates the insulation layer, and rain on reversed roof, according to Annex A (normative).

U = U´ + ∆U where U’ is the uncorrected transmission coefficient in W/m2 K

∆U is the correction, estimated according to Annex A (normative).

Resulting U-values are indicated to 2 decimals. 6.2 Surface heat flow resistance

For plane surfaces the values in table 6.2.1 are to be used, if no more precise specifications are at hand. The values for horizontal are used for heat flows that deviate no more than 30° from the horizontal plane. For non-plane surfaces or special surface conditions the procedure in Annex A of DS/EN ISO 6946 is used.

For building components with unknown heat flow direction, the values for horizontal heat flow are used.

Table 6.2.1 – Surface resistance m2K/W

The heat flow’s direction

Upwards Horizontal Downwards

Rsi 0,10 0,13 0,17

Rse 0,04 0,04 0,04 6.3 Heat flow resistance for a material layer

The resistance for an unbroken homogenous material layer is

where d is the thickness of the material layer in m.

is the design thermal conductivity for material or product in W/mK (see chapter 7).

For compressible materials the thickness of the material layer in the completed construction is to be ap-plied. For loose material fillings injected into attics the permanent insulation thickness after subsidence is applicable. Thus the insulation has to be injected with an oversize according to relevant product standard or table 6.3.1.

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In order to prevent subsidence in closed cavities, horizontal and vertical, the material has to be injected with minimum density according to relevant product standard or table 6.3.

λ is the design thermal conductivity of the material or the product in W/mK. Regarding values of λ see Chapter 7.

Table 6.3 – Oversize/density for loose material fillings

Insulation material Minimum oversize

loosely injected into attics

Minimum density injected in cavities

Horizontal kg/m3

Vertical kg/m3

Glass wool filling +5% 30 55

Rock wool filling +5% 50 65

Expanded polystyrene, balls 1) 20 20

Expanded polystyrene, filling 1) 15 15

Cellulose fibers +25% 50 65

Expanded perlite 0% No demand No demand 1) These materials not to be applied in ceilings and attics

Measurement of thickness The thickness of the layer of loose material filling is to be measured according to DS/EN 823. Measuring is done using a plate, that provides a load impact of 20 ± 1.5 Pa.

6.4 Heat flow resistance for air filled cavities

The Values in this chapter is valid for air filled cavities which are: • Limited by parallel surfaces perpendicular to the heat flow and having an emission rate larger than 0.8. • Has a depth in direction of the heat flow of less than 0.1 times the smallest dimension of the cavities

length or width, however no more than 0.3 m. If the above mentioned requirements are not meet, the procedure in Annex B DS/EN ISO 6946 are to be used.

The heat flow resistance for components with cavities depths larger than 0.3 m cannot be calculated. The heat flow can instead be calculated as indicated in DS/EN ISO 13789.

6.4.1 Non-ventilated cavities

For constructions with non-ventilated cavities the values in table 6.4.1 is used.

Table 6.4.1 – Heat flow resistance for non-ventilated cavities m2K/W

Cavity depth mm

Heat flow direction

Upwards Horizontal Downwards 0 0.00 0.00 0.00 5 0.11 0.11 0.11 7 0.13 0.13 0.13 10 0.15 0.15 0.15 15 0.16 0.17 0.17 25 0.16 0.18 0.19 50 0.16 0.18 0.21 100 0.16 0.18 0.22 300 0.16 0.18 0.23

Note – For values in between linear interpolation can be used

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An air layer, which doesn’t have an insulating layer on the outside, but has small openings towards the outside air, must also be considered as an non-ventilated cavity, provided that these openings are not meant as ventilation for the cavity and the area of the openings doesn’t exceed:

5 cm2 pr. m horizontal length for vertical cavities 5 cm2 pr. m2 surface area for horizontal cavities

Drainage openings made as vertical joints, are not considered as ventilation openings.

6.4.2 Slightly ventilated cavities

By slightly ventilated cavities is meant cavities where ventilation towards the outside air, is created by openings which are:

Vertical cavities > 5 cm2, but < 15 cm2 pr. m horizontal length. Horizontal cavities > 5 cm2, but < 15 cm2 pr. m2 surface area.

For these cavities the heat flow resistance is set to half the value of those in table 6.4.1. If the heat flow resistance for an external facing exceed 0.15 m2K/W, a heat flow resistance of no more than 0.15 m2K/W must be taken to account. This comes to use e.g. by facing brick wall and wooden facing thicker than 20mm.

6.4.3 Ventilated cavities

By Ventilated cavities is meant cavities where ventilation towards the outside air, is created by openings which exceed:

15 cm2 pr. m horizontal length for vertical cavities 15 cm2 pr. m2 surface area for horizontal cavities.

When calculating the heat flow resistance for a component containing a ventilated cavity, the heat flow resistance for the cavity and all other layers between the cavity and the outside surface, is set to the value of the inner surface resistance for the construction (see chapter 6.2).

6.4.4 Not ventilated cavities with reflective surfaces Design values can be decided in connection with calculation or measuring with relation to the follow-ing rules:

For cavities limited by, parallel, reflective planes the heat flow resistance are calculated with relation to DS/EN ISO 6946 annex B (normative) For other use of reflective insulation the heat flow resistance is determined in connection with meas-uring with relation to DS/EN ISO 8990. The reflective surfaces are influenced normally by corrosion or smudging, by means of which the heat flow resistance is reduced considerably. In these cases the heat flow resistance is to be calcu-lated with relation to section 6.4.1.

6.5 Ventilated attics

The values in table 6.5.1 are to be used for cold, ventilated attics. The heat flow resistance is applied to the ceiling-area, regardless of an eventual angel between the roof and the ceiling. The values are the total heat flow resistance for attic and roof covering.

Table 6.5.1 – Total heat flow resistance for attics and roof covering

Type of roof cover m2 K/W Steel or metal sheet 0,1

Fibre cement shingles or – corrugated sheets on battens 0,2

Roof tile with ceiled joints on battens 0,2

Roof tiles on battens with wind proof under layer 0,3

Bitumen felt on roof of 25 mm wood 0,3 Thatched roof with wind proof under layer 0,3

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6.6 Constructions with inhomogeneous material layers

If a building component – e.g. a timber frame structure or brickwork with joints - consist of homo-geneous and inhomogeneous plane parallel layers, the heat flow resistance is to be calculated, as if each of the inhomogeneous layers in fact is homogeneous layer with a heat transmission capabil-ity which is an estimated average value of the heat transmission capability of the different sections of the layer.

The heat flow resistance for battens, meaning layers comprising 19-25 mm boards put up with in-ternal distances and thus providing hollow space, is set to 0.16 m2 K/W. The same value is normal-ly to be applied for the cavity just underneath the floorboards on floor joists.

1′ ′

where

′. .

. .

Rsi is the inner surface resistance in m2 K/W Rse is the outer surface resistance in m2 K/W Rh is the resistance of homogeneous layer in m2 K/W d is the thickness of inhomogeneous layer in m ’ is the estimated average thermal conductivity of the inhomogeneous layer in W/mK Aa, Ab is the area of inhomogeneous layer sections in m2

ab is the applicable thermal conductivity in W/mK 6.7 Constructions with cold bridges

When estimating the transmission coefficient for a construction, possible thermal bridges as well as the im-pact of reduced insulation thickness in parts of the construction should be taken into account, if they are not calculated separately. Such thermal bridges could be:

• Brick work filling and ribs for instance around windows and doors • Wall penetrations of for instance metal, concrete or tile. • Joints in corners

The transmission coefficient for a construction including thermal bridges and reduced insulation thickness in parts of the construction is to be calculated using the formula:

where A is the total transmission area in m2 of the construction, see chapter 3.6 Ai is the sub area in m2

Ui is the transmission coefficient of the sub area with a one-dimensional heat flow in W/m2 K lk is the length of the individual linear thermal bridge in m, see chapter 3.7

Ψk is the linear heat loss for the individual linear thermal bridge in W/mK χj is the point heat loss for the individual spot thermal bridge in W/K n is the number of sub areas m is the number of linear thermal bridges

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When using loose filling of insulation material, the thickness of the insulation layer is equivalent to a width of the cavity. If insulation slabs are used, the thickness of the insulation layer is equivalent to the slab thickness, however, not more than the width of the applicable cavity. The transmission coefficient Ui for the sub areas is to be calculated, as if only one dimensional heat flow oc-cur. For continuing storey partitions, beams and columns for instance of concrete or steel, the transmission Ui for the sub area is to be estimated as if the storey partition, the beam or the column are in the same level as the actual construction surface, for instance the surface of the walls. The linear heat loss Ψk is covering only the increasing heat loss through the thermal bridge because of two dimensional heat flows related to the heat loss calculated for one dimensional heat flow. The point heat loss (transmission coefficient for point – thermal bridge) χj is covering the total increase of heat loss due to the thermal bridge. The thermal bridge impact including the impact of the two and three dimensional heat flows is taken into ac-count in the transmission coefficient U’ for the construction, where the thermal bridge appears. The thermal bridge impact in corner joints between building components for instance the connection between basement deck, outer wall and basement outer wall as well as the connection of outer wall and ceiling is to be included in the U’- value for the building components that appear in the joint. The calculation should show how the thermal bridge impact is distributed on the U’-values of the individual building components. Thermal bridges in for instance corners of outer walls, in connections between basement deck, outer walls and basement walls as well as the connection between outer wall and ceiling may normally be neglected, provided that the insulation is continuing uninterrupted or only interrupted of material with a thermal conduc-tivity lesser than 0.3 W/m K, for instance wood or lightweight concrete with a low density. The following shows values for common thermal bridges in typical constructions. For constructions with simi-lar structure, but different insulation thickness and heat transmission capability, interpolation in the tables are allowed. When calculating the transmission coefficient for a construction, linear heat loss Ψk less than 0.02 W/m K and point heat loss χj less than 0.02 W/K, may be neglected. For other constructions the linear heat loss can be calculated as described in annex B. However, it is provided, that the total heat loss due to linear thermal bridge and point thermal bridges, is in-significant in relation to the total heat loss of the construction. It should always be appraised, if there might be other thermal bridges that may have significant impact on the heat loss, the constructions or the indoor cli-mate. Where values or figures in the following tables are shown in bracket it is indicating that the applicable linear loss or spot heat loss or brick tie correction may be neglected when calculating the transmission coefficient U’ for a construction, however, observing the provisions mentioned above. 6.7.1 Brick ties For the brick ties correction ∆Uf refer to the values or the formula in Annex A (normative). 6.7.2 Pillars and ribs The linear loss Ψk for pillars and ribs in cavity walls is shown in table 6.7.1. The values in the table are appli-cable for every single change of insulation thickness, see figure 6.7.1. In case of two changes in insulation thickness for instance on each side of a rib, both changes should be taken into account. The linear loss is to be seen as an addition to the one dimensional heat flow through the thermal bridge. The heat loss taking place through the joint between construction and windows or doors is calculated sepa-rately, see chapter 6.12.

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a. Pillar near window opening b. Pillar in outer wall section One change of insulation thickness Two changes of insulation thickness Each one of the changes in insulation thickness is shown/indicated in the figures with a set of arrows pointing towards each other and towards the change of insulation thickness. Figure 6.7.1 – Example of a single change of insulation thickness due to pillars/ribs near window opening and a pillar in a longer part of an external wall section.

Table 6.7.1 – The linear loss Ψk in W/mK for pillars and ribs in cavity walls depending on cold bridge insulation and material.

Cold bridge insulation with thermal conductivity not exceeding 0.04 W/m K. Pillars and ribs in the rear wall are provided of the same material as the rear wall. Pillars and ribs in the front wall are provided of the same material as the front wall. The values in the table are for each individual change of insulation thickness, see figure 6.7.1.

Cold bridge interruption

Outer leaf: Concrete1) Tile Tile Tile Lightweight concrete3)

Inner leaf: Concrete1) Concrete1) Tile2) Lightweight concrete3) Lightweight concrete3)

None 0.24 0.14 0.05 0.02 (0.01)10mm 0.06 0.05 0.03 (0.01)20mm 0.04 0.03 0.0230mm 0.03 0.02 (0.01)40mm 0.02 (0.01) 50 mm (0,01)

1) Reinforced concrete with 2% reinforcement bars 2) Applies also for light weight concrete with a thermal conductivity 0.7 W/mK 3) Light weight concrete with thermal conductivity 0.3 W/mK

Note! Table 6.7.1. cannot be used to estimate linear loss for doors and windows on foundation, but this refers to chapter 6.13.2. 6.7.3. Change in the plane of the insulation The linear loss Ψk for constructions with change in the plane of the insulation, e.g. joints between external wall and basement wall is stated in table 6.7.2. Using the values it is provided that there is an overlap be-tween the insulation in the two planes, see figure 6.7.2. If there is no overlap, the values in table 6.7.1 are to be used combined with calculation of the one dimensional heat flow through the un-insulated part of the con-struction.

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Table 6.7.2 – Linear loss Ψk for constructions with change in the plane of the insulation and with up to 12 cm sidepieces between the two layers of insulation.

The values is for constructions towards the open air, but can also be applied to constructions under the level of the terrain. It is allowed to interpolate in the values of the table.

Overlap Internal insulation mm

Concrete1) λ = 2,0 W/mK

Tiles2) λ = 0,7 W/mK

Light weight concrete λ = 0,3 W/mK

0 mm 0

100 200

0,67 0,15 0,07

0,25 0,08 0,04

0,09 0,04 0,02

300 mm 0

100 200

0,35 0,11 0,05

0,12 0,05 0,03

0,05 0,02 0,01

600 mm 0

100 200

0,24 0,09 0,05

0,09 0,04 0,02

0,04 0,02 0,01

1) Concrete without reinforcement 2) Applies also for light weight concrete with a thermal conductivity 0.7 W/mK

Figure 6.7.2 Construction with change in the plane of the insulation and overlap in the in-sulation layers

6.7.4 Steel plate profiles in steel frame walls The linear loss Ψk for continuing profiles of metallic materials in framed walls the value 0.15 W/K per meter profile is to be applied. The value comprises the total heat flow through the profile including the one dimen-sional heat flow, provided the thickness of the profile is not exceeding 2.0 mm. The heat flow may be re-duced when using perforated/cut profiles. In those cases the heat flow is to be calculated for the applicable profile. For the transmission coefficient for point thermal bridges χj, where steel profiles are crossing each other in steel frame walls, the value 0.08 W/K is to be applied for each crossing. The value covers the total heat flow through the profile crossing provided that the thickness of the profile does not exceed 2.0 mm. 6.7.5 Foundations under partitioning wall The linear loss Ψk for partition wall foundations, which continue through the insulation of a terrain floor, is shown in table 6.7.3. The heat loss through the outer wall foundation near terrain floors is to be calculated separately, see chapter 6.13.

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Table 6.7.3 – The linear loss Ψk in W/m K for partition wall foundations, that penetrate the insulation of ground deck or basement floors.

The values in the table are applicable for each individual change of insulation thickness (see figure 6.7.3) Foundation structure W/m K

Concrete with λ = 2.0

Light weight concrete with λ = 0.25 on the upper 20 cm

Light weight concrete with λ = 0.25 on the upper 40 cm

0,09

0,03

(0,01)

Two single changes in the insulation thickness are shown – one on each side of the foundation. Each one of the single changes is indicated in the figure with a set of arrows, pointing at each other and towards single change.

Figure 6.7.3 – Example of single change of insulation thickness at a partition wall foundation.

6.7.6 Other penetrations For the linear loss Ψk for concrete deck and -walls, penetrating cavity walls, as well as for concrete columns and concrete beams in cavity walls (see figure 6.7.4) the values in table 6.7.4 apply. The transmission coefficient Ui for the sub area is to be calculated as if the deck or the wall is ending flush with the actual construction surface. The linear loss is seen as an addition to the one dimensional heat flow through the thermal bridge. The one dimensional heat flow at the end of external walls in corners by concrete- pillars and beams are neglected. The values in table 6.7.4 for concrete- pillars and beams in corners thus covers the total one dimensional heat flow thru the pillar or the beam and the two dimensional heat flow thru the connected cavity walls. The values for the transmission coefficient for point-thermal bridge χj for penetrating columns and beams are shown in table 6.7.5.

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Table 6.7.4 – Linear loss Ψk in W/m K for continuing concrete-deck1) and - walls1), that penetrate cavi-ty walls, and for concrete-columns1) and -beams1) in cavity walls

The values in the table apply for cavity walls of bricks, where the heat transmission capacity of the tile does not exceed 0.7 W/mK. The values are applicable for each single change of insulation thickness Thermal bridge W/m K Continuing concrete deck or –wall Concrete-column or -beam in full wall size Concrete-column or -beam in outgoing corner Concrete-column or -beam in ingoing corner

0,13 0,15 0,45 0,55

1) Concrete with 2 volume-% reinforcement bars

Continuing concrete deck Concrete column in Concrete column in corner

full wall width

Figure 6.7.4 – Examples on continuing concrete deck and -walls penetrating cavity walls and ex-

amples of concrete columns and beams in cavity walls.

Table 6.7.5 – Transmission coefficient χj in W/m2K for continuing beams and columns of concrete, bricks or steel – see figure 6.7.5.

Material χj

W/m2K

Brick1) Reinforced concrete with 2 volume-% reinforcement bars Stainless steel Steel

A

11 A

60 A

170 A

Is also valid for light weight concrete with = 0,7 W/mK

A is the cross area of the beam or the column. For profiles of steel or stainless steel the value must not be less than χj = 10 x Ao, where Ao is the area in m2 of smallest possible rectangle embracing the profile, see figure 6.7.6

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Figure 6.7.5 – Continuing beam Figure 6.7.6 – Determination of smallest embracing rectangle

6.8 Windows, external doors etc.

The transmission coefficient for windows and outer doors, including gates, glass walls, hatches, skylights, dormer windows towards the free, towards unheated rooms and between spaces heated to different temperature, are de-cided and declared (by the producer) like pointed out in the harmonized product standards DS/EN 1873, DS/EN 14351-1 and DS/EN 14963. If there aren't a provision and declaration with relation to the above mentioned, or if they do not constitute a suffi-cient basis for a calculation of the building's heat loss, the heat transmission coefficient is to be decided according to this section 6.8.

6.8.1 Calculation of U-value

U-values are calculated from the basic formula:

where

Ag is the glass area in m2 (by glass can be understood other corresponding materials)

Lg is the circumference of the glass area in m

Ap is the panel area in m2

Af is the frame/casing area1) in m2

Lk is the length of other linear cold bridges in m

Ug is the transmission coefficient in the middle of the pane in W/m2K g is the linear loss for the pane’s distance profile in W/mK Up is the transmission coefficient for the panel in W/m2K Uf is the transmission coefficient for frame/casing1) in W/m2K k is the linear loss for other cold bridges in W/mK 1) “frame/casing” also includes bars and posts.

The expression can be used for:

Different types of panes (glass, plastic, one- or more layer panes, with or without coating and with cavities filled with other gasses than air)

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Different frame/casing materials (e.g. wood, plastic, metal with or without cold bridge interruption, combina-tions of different materials)

Opaque panels used in frames in windows and doors.

6.8.1.1 Determination of transmission areas (A) and length (l) Also see section 3.6. In the window’s or the door’s resulting transmission area is included a possible caulking joint, which is assigned to the same transmission coefficient U as the window or door. Ag – The glass area Is determined by the light opening in the window or the doorway that the pane is built into. The glass area's circum-ference lg is determinede like the circumference of the light opening. The panel’s area Ap is decided in correspond-ing way like the glass area. 6.8.1.2 Determination of transmission coefficients (U) For windows and skylight the U value have to be known for the topical window slope. Ug - The transmission coefficient in the middle of a pane (where the heat transmission through the distance profile is ignored). For double-glazed windows as well as for panes in coupled or independent frameworks the assets in figure N.1. – N.4.are valid, unless a more precise value has been determined. For a single vertical glass layer is Ug = 5.9 W/m²K. For other pane types the transmission coefficient must be determined in other ways (see e.g. annex l). Up - the Transmission coefficient for panels and for door plates Are determined as for other building components, see sections 6.1 to 6.7. Uf – Transmission coefficient in W/m²K for frameworks and window frames made of wood For frameworks and window frames made of wood or covered wood the transmission coefficient is determined from figure 6.8.1, unless a more precise value has been decided according to DS/EN ISO 10077-2 or DS/EN 12412-2. By the provision of the thickness of frameworks and window frames made of wood possible coverings of metal or plastic can be ignored. At different thickness of e.g. casing and window frame the mean value is used. At coupled frameworks the overall thickness of the framework is used.

Curve A is for hard wood

Curve B is for pine and fir

Figure 6.8.1 – Transmission coefficient Uf in W/m2K for frame/casing of wood

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Uf – Transmission coefficient in W/m²K for frameworks and window frames of plastic or metal For frameworks and window frames of plastic or metal the transmission coefficients indicated in table 6.8.1. are used. For PUR- profiles the metal reinforcement is assumed covered with at least 5 mm of polyurethane foam. For PVC profiles are assumed that at most there is metal reinforcement in one chamber, and that the distance be-tween the wall surfaces in all chambers is at least 5 mm. The transmission coefficient for metal profiles with broken cold bridge very much depends on the detail working out and must therefore be determined specifically for each profile. The use of the value for metal profiles in table 6.8.1 presupposes:

that the overall, external surface area for the profile is used by the determination of the heat flow that there are no flanges, coverings or fins on the profile, which increases the out- or inside surface area that the profile's width is greater than the profile's depth.

Tabel 6.8.1 – Transmission coefficient Uf in W/m²K for frameworks and window frames of plastic- or metal

profiles W/m²K

Plastic profiles

PUR-profiles

PVC-profiles, 2 chambers

PVC-profiles, 3 chambers

2,6

2,1

1,9

Metal profiles

without broken cold bridges

5,9

For other metal profiles, including slim, through-going profiles and profiles with flanges, coverings or fins, the transmission coefficients Uf and f for the profile must be determined by two-dimensional calculation or measuring. Through-going metal profiles should be avoided. Other U-values For windows with independent frameworks and a distance between the frameworks of at least 10 mm the trans-mission coefficient is calculated as

11⁄ 1⁄

where Ue and Ui are the transmission coefficients for respectively the exterior and the inside part of the window. For bottom frames in doors or windows to floor, where an aluminum bottom rail or the like metal profile without cold bridge interruption is used, should be used an Uf corresponding the value in table 6.8.1 for metal profiles without broken cold bridges. It always has to be reckoned whether there are other cold bridges, which may be important for the heat loss, e.g. metal profiles in frame/casing in skylights. The linear loss k for such thermal bridges is determined by detailed calculation. See e.g. annex H. If the transmission coefficient for a skylight or dormer window is determined, without having considered the heat loss through the side of the frame, the window's transmission coefficient should be increased corresponding the heat loss through the side of the window frame. The heat loss through the side of the window's frame is deter-mined by using the values in table 6.12.4 and measuring the window frame's height from the top side of the con-nection to the outer top side of the glass, see figure 6.12.3. Are windows and doors equipped with mobile insulation, e.g. insulating shutters, this isn’t taken into consideration at calculation of U values and heat loss frame. The same is valid at calculation of design heat loss. By energy frame calculations the effect of mobile insulation can be included.

6.8.1.3 Determination of linear loss () g - The Linear loss for the pane's distance profile

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g covers the overall two-dimensional heat flow through the distance profile and the connection between pane and window frame, or bar. In connection with bar working outs with through-going glass layers and with distance profile table 6.8.2. or table 6.8.3 can also be used, unless a more precise value has been determined. g can be equal to 0 for windows with single glass layer or with a single glass layers in coupled or independent wooden frames or for bars in front of through-going glass without distance profile. 6.8.2 Other methods for determination of transmission coefficients Relevant standards and proposals for standards have been mentioned in annex K. Measuring of the U value in the specific working out, building-in and size of windows and doors. Use of annex H and I in this standard:

Annex H is a detailed calculation method for the overall U value for skylight Annex I is a calculation example for a window with a two-layer pane.

Are other methods used for the determination of U (see below), the principle building up of the formula in front of section 6.8.1 however is always followed, just as it always has to be pointed out, how transmission coefficients have been determined. Is the transmission coefficient known, e.g. from a testing, for a reference window with given dimensions, the trans-mission coefficient can for a window with other dimensions be calculated - however the same window construction, pane transmission coefficient, pane distance profile and frame/casing profile is demanded. It's assumed that the same profile is used in the whole window. In cases of doubt the hotbox method is used like pointed out in DS/EN ISO 12567-1 and DS/EN ISO 12567- 2, which can be used for the testing of complete windows and doors respec-tively dormer windows and corresponding windows. For the reference window is calculated the thermal coupling coefficient Lf for the window's overall frame/casing and post profiles by the expression:

where

A1 is the complete window area of the reference window in m2

Ag1 is the glass area of the reference window in m2

U1 is the complete transmission coefficient for the reference window in W/m²K

Ug is the transmission coefficient in the middle of the pane in W/m²K

lf1 is the reference window's overall profile length in m, that is external frame measure plus the length of a pos-sible post.

For the topical window of the same type as the reference window, but with other dimension, the transmission coef-ficient is determined by the expression:

where

A2 is the complete window area of the topical window in m2

Ag2 is the glass area of the reference topical in m2

U2 is the complete transmission coefficient for the topical window in W/m²K Lf2 is the topical window's overall profile length in m, that is external frame measure plus the length of a possible

post.

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The transmission coefficient calculated for the topical window can thus be split up into 2 components:

U2 = U1 (1 + )

Where the factor can be calculated as:

6.8.3 Other figures and tables for determination of U

Table 6.8.2 – Linear loss g in W/mK for frame/casing and window frames of metal profiles with broken thermal bridges and with distance profiles in different materials in dependence on the pane's U- value

(which can be interpolated in the table)

The pane’s U-value (W/m2K) Aluminum or ordinary steel Thermal improved profile, stainless steel or similar1)

0,5 – 1,2 0,11 0,08 2,7 – 3,0 0,08 Not relevant

1) A thermal improved distance profile is defined from the following formula:

(d· )< 0.007 (the criterion have to be fulfilled, so that the value in the table can be used). d is the distance profile's thickness of material in meters (see figure 6.8.2).

is distance profile's thermal conductivity in W/mK as pointed out in table F.1. If the obligatory summation not reasonably can be made, because the distance profile has been built up by a com-bination of materials with different thermal conductivity, which isn't through-going in the direction of the heat flow, the linear loss should be calculated according to DS/EN ISO 10077-2.

Tabel 6.8.3 - Linear loss g in W/mK for frame/casing and window frames of wood- or plastic profiles and

with distance profiles in different materials in dependence on the pane's U- value (which can be interpolat-ed in the table)

The pane’s U-value

(W/m2K) Aluminum or ordinary steel Thermal improved profile,

stainless steel or similar1) Plastic

0,5 – 1,2 0,08 0,06 0,05 2,7 – 3,0 0,06 Not relevant Not relevant

1) A thermal improved distance profile is defined from the following formula:

(d· )< 0.007 (the criterion have to be fulfilled, so that the value in the table can be used). d is the distance profile's thickness of material in meters (see figure 6.8.2).

is distance profile's thermal conductivity in W/mK as pointed out in table F.1. If the obligatory summation not reasonably can be made, because the distance profile has been built up by a com-bination of materials with different thermal conductivity, which isn't through-going in the direction of the heat flow, the linear loss should be calculated according to DS/EN ISO 10077-2.

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Figure 6.8.2 - Examples of the determination of criterion for thermal improved distance profiles - hollow profile a) and firm sealing B)

Example- For a typical hollow profile in 0.15 mm stainless steel can (d· ) be estimated at: 2 x 0.00015 x17 = 0.005 1, and it thus fulfils the criterion and occurs under the category thermal improved distance profile.

6.9 Ground supported floors, basement floors and basement walls against soil

The transmission coefficient for a ground supported floor or a basement wall directly towards soil is de-termined from the formula:

where

Rsi is the inner surface resistance in m2K/W, see table 6.2.1 Rj is the resistance of the soil in m2K/W, see table 6.9.1 Rm is the resistance for material layers in the actual floor or wall construction in m2K/W

The resistance of the soil does also include an eventual external surface resistance at the ground surface. For constructions with floor heating, the resistance is calculated from the plane of the heating source as neither the resistance of layers above this plane nor the inner surface resistance is included in the transmission coefficient. For ground supported floors and basement floors the depth is measured to the upper side of the finished floor. For basement walls the depth is measured to the upper side of the basement foundation. The resistance Rj found in table 6.9.1 for basement walls until a depth of 2 m is an average resistance for the wall until the depth of 2 m. Deep basement walls are divided into an area of the depth of 2 m and an area of the depth of more than 2 m. When calculation the resistance for floor constructions the capillary breaking layers can be included. The part of the basement wall, which extends above the ground surface is calculated as walls towards the open air.

Table 6.9.1 – Resistance for soil Rj

Component m2 K/W

Ground supported floor, from 0.5 m above to 0.5 m below the terrain Basement floors, deeper than 0.5 m below the terrain Basement walls Until 2 m below the terrain (h is the depth in m) More than 2 m below the terrain and under the building

1,5 2,0

0,2 + 0,3h

2,0

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6.10 Concrete sandwich elements

In concrete-sandwich elements the overall length of linear thermal bridges is normally so great that the linear losses should be included in the calculation of the element's overall transmission loss, even though the linear loss Ψk is less than 0.02 W/mK. In figure 6.10.1 is shown the linear loss in dependence on insulation thickness in element and next to ribs. Annex J contains a calculation exam-ple.

Figur 6.10.1 – Linear loss Ψk for concrete sandwich elements (reinforced concrete with 2 volume-% steel) in dependence on insulation in element and next to ribs.

Insulation with thermal conductivity at most 0.04 W/mK

6.11 Wedged insulation – Calculation of U-value Is the U value for wedge-shaped insulation calculated as for plan-parallel surfaces with a

thickness that corresponds to the average thickness, the result will not become correct. In DS/EN ISO 6946 is described a procedure, which is more correct. It's used in DS 418: Wedge-shaped insulation is divided area-wise as shown in figure 6.11.1.

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Figure 6.11.1 – Subdivision of roof There are four types of wedges with matching formulas for calculation of the U-value for the construction.

Figure 6.11.2 – Wedge type A – Rectangular area

Figure 6.11.3 – Wedge type B – Triangular area thickest by top point

Figure 6.11.4 – Wedge type C - Triangular area thinnest by top point

Figure 6.11.5 – Wedge type D - Triangular area thickest with different thickness top

point For all wedge types are valid: R0 is the design heat resistance of the remaining part of the construction including surface resistances on both sides d1 is the thickness of "the intermediate layer" d2 is the maximal thickness of the wedge.

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6.12 Joints around windows and doors

The linear loss Ψsa for joints around windows and doors is determined as in section 6.12.1 – 6.12.4. Nor-mally linear heat losses (Ψsa) that are less than 0.02 W/mK may be neglected. Special built together-details that are not covered by the tables, the linear loss must be calculated like pointed out in annex c. Normally linear losses (Ψsa) less than 0.01 W/mK can be ignored The line loss Ψk for the thermal bridge between windows/doors and foundations appears in section 6.13.2.

6.12.1 Linear loss Ψs in W/mK for joints around windows and doors in cavity walls Joints with reduced insulation thickness Preconditions of the values in the tables 6.12.1a-b concerning thermal bridge insulation with thermal con-ductivity less than 0.04 W/mK:

Frame depth no less than 90 mm Regarding placement of the frame, see figure 6.12.1.

Table 6.12.1a – The frame placed in front of the cold bridge interruption in a wall with at least 20 mm

overlapping respectively the front wall and the rear wall (see figure 6.12.1,sketch 1 below). Cold bridge interruption

Outer leaf: concrete1) Brick Brick Brick Light weight concrete3) Inner leaf: concrete1) concrete1) Brick2) Light weight concrete3) Light weight concrete3)

None 0,25 0,13 0,11 0,09 0,06 10 mm 0,05 0,05 0,05 0,05 0,05

20 mm 0,04 0,04 0,04 0,04 0,04

30 mm 0,03 0,03 0,03 0,03 0,03

40 mm 0,02 0,02 0,02 0,02 0,02

50 mm 0,01 0,01 0,01 0,01 0,01

1) Reinforced concrete with 2 volume-% steel. 2) Is also valid for light weight concrete with thermal conductivity 0,7 W/mK. 3) Light weight concrete with thermal conductivity 0,3 W/mK.

Table 6.12.1b – The frame displaced from the thermal bridge insulation in the wall for in-

stance either next to the front wall or next to the rear wall (see figure 6.12.1, sketch 2 below).

Cold bridge interruption

Outer leaf: concrete1) Brick Brick Brick Light weight concrete3) Inner leaf: concrete1) concrete1) Brick2) Light weight concrete3) Light weight concrete3)

None 0,34 0,17 0,17 0,17 0,10 10 mm 0,12 0,11 0,11 0,11 0,08

>10 mm 0,11 0,09 0,09 0,09 0,07

1) Reinforced concrete with 2 volume-% steel. 2) Is also valid for light weight concrete with thermal conductivity 0,7 W/mK. 3) Light weight concrete with thermal conductivity 0,3 W/mK.

Joints, where the wall insulation is led out in the fold in its full thickness Preconditions for the values in the tables 6.12.1c-d concerning insulation with thermal conductivity less than 0.04 W/mK:

Outer wall with thickness of at most 110 mm Deck plate carried out in wood or wood-based plates Concerning the frame's location, see figure 6.12.1.

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Table 6.12.1c - Frame placed with at most 30 mm of overlap concerning front wall or rear wall (see figure 6.12.1, sketch 3 below)

Insulation thickness

Frame depth: 60 mm4) 120 mm5) Front wall: Concrete1) Brick2) Light weight concrete3) Concrete1) Brick2) Light weight concrete3)

125 mm 0,03 0,02 0,02 0,01 0,01 0,01 250 mm 0,04 0,03 0,03 0,02 0,02 0,02

500 mm 0,05 0,05 0,04 0,04 0,03 0,03 1) Reinforced concrete with 1 volume-% steel and thermal conductivity 2,5 W/mK. 2) Brick with thermal conductivity 0,7 W/mK. 3) Light weight concrete with thermal conductivity 0,3 W/mK. 4) Deck plate of stone (marble etc.) increase the linear loss with 10% by 125 mm insulation and 20% by 500 mm insulation. Interpolation is possible. 5) Deck plate of stone (marble etc.) increase the linear loss with 5% by 125 mm insulation and 10% by 500 mm insulation. Interpolation is possible.

Table 6.12.1d - Frame placed dislocated from the outer wall insulation next to either front- or rear wall

(see figure 6.12.1, sketch 4 below) Insulation thickness

Frame depth: 60 mm6) 120 mm7) Front wall: Concrete1)4) Brick2) Light weight concrete3) Concrete1)5) Brick2) Light weight concrete3)

125 mm 0,13 0,11 0,08 0,08 0,07 0,05 250 mm 0,15 0,12 0,09 0,10 0,08 0,06

500 mm 0,16 0,14 0,11 0,11 0,10 0,08

1) Reinforced concrete with 1 volume-% steel and thermal conductivity 2,5 W/mK. 2) Brick with thermal conductivity 0,7 W/mK. 3) Light weight concrete with thermal conductivity 0,3 W/mK. 4) At sandwich element with 70 mm of front casting the linear loss can be reduced with 0.06 W/mK 5) At sandwich element with 70 mm of front casting the linear loss can be reduced with 0.05 W/mK 6) Deck plate of stone (marble etc.) increase the linear loss with 20%. 7) Deck plate of stone (marble etc.) increase the linear loss with 10%

Joints around windows and doors mounted in a displaced fold Preconditions for the values in the tables 6.12.1e-f:

Cold bridge insulation with thermal conductivity less than 0.04 W/mK Wooden windows with frame depth of at least 100 mm Concerning the frame's location, see figure 6.12.1.

Table 6.12.1e - Displacement of rear wall - frame placed respectively displaced from the outer wall insu-

lation next to either front- or rear wall or with at most 30 mm overlap to front- or rear wall (see figure 6.12.1, sketch 5 below)

Insulation thickness

The frame’s Displaced from insulation location

Overlap to front- or rear wall

Front wall: Concrete1) Brick2) Light weight concrete3) Concrete1) Brick2) Light weight concrete3)

125 mm 0,06 0,05 0,04 0,01 0,01 0,01 250 mm 0,07 0,06 0,05 0,02 0,02 0,02

500 mm 0,08 0,08 0,06 0,03 0,03 0,03 1) Reinforced concrete with 1 volume-% steel and thermal conductivity 2,5 W/mK. 2) Brick with thermal conductivity 0,7 W/mK. 3) Light weight concrete with thermal conductivity 0,3 W/mK.

Table 6.12.1f - Displacement of front wall up in front of the frame (see figure 6.12.1, sketch 6 below) Insulation thickness Linear loss

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125 mm 250 mm 500 mm

0,00 0,01 0,02

Figure 6.12.1 – The frame’s placing in window- or door-openings in hole in wall

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6.12.2 The The linear loss Ψsa for the joint around windows and doors in insulated timber frame walls with lightweight cladding or with brick work front wall.

Table 6.12.2 – The joint around windows and doors in insulated timber frame walls with

lighweight cladding or with brick work front wall

Placement of frame W/mK In line with the insulation 60 mm overlapping to the insulation

20 mm overlapping Displaced form the insulation

(0,00) 0,03 0,08

Values in table 6.12.1b for for “no” cold bridge interruption

not shown in sketch see sketch 7 below see sketch 8 below see sketch 9 below

The values in the table 6.12.2 provides: Frame depth no less than 90mm Placement of the frame see figure 6.12.2

Figure 6.12.2 – The placement of window- and doorframes in openings in timber frame con-

structions with brickwork front wall. The values in table 6.12.2 also apply for massive outer walls with external insulation in timber frame con-struction or with insulation fastened directly on the massive part of the outer wall. For outer walls with external insulation covered by rendering, ceramic tiles or alike, continuing behind the window- or doorframes, the values according to table 6.12.1 apply.

6.12.3 The linear loss Ψsa for the joint around windows and doors in front of metal frames in insu-lated frame walls with light weight cladding or with a brick work front wall.

Table 6.12.3 – The joint around windows and doors in front of metal frames in insulated frame

walls with light weight cladding or with a brick work front wall and for solid outer walls with insulation e.g. between metal profiles

Placement of frame Ψsa W/mK

In line with the insulation and the metal profile 60 mm overlap to the insulation and metal profile 20 mm overlap to the insulation and metal profile Displaced form the line of the insulation (see figure 6.12.2, sketch 9)

0,15 0,11 0,13

Values in table 6.12.1b for front wall and no cold bridge interrup-

tion

The values in table 6.12.3 provides

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Frame depth no less than 90mm Regarding placement of the frame see figure 6.12.2

The values in table 6.12.3 also apply for massive outer walls with external insulation between metal frame profiles. The values express the heat loss through the joints provided that the thickness of the metal frames are not exceeding 2,0 mm. The heat flow can be reduced by using perforated profiles. In this case the heat flow has to be determined for the actual profile.

6.12.4 The linear loss Ψs for joints around roof light and skylight including connecting panels and frame.

The height of the joint is measured from upper side of insulation in the roof construction to bottom side of the frame in the skylight and to the upper side of the insulation on the side of the frames in roof windows, se figure 6.12.3. Application of the values in table 6.12.4 provides that the frame is made of wood without through-going or partly through-going metal profiles, and that the heat flow ca-pability of the insulation does not exceed 0.04 W/m K.

For other joint measurements and insulation thickness’ interpolation is permitted. If the joint com-prise both sections with and without insulation, the linear loss is determined on the basis of an esti-mated average taken into account the areas of no insulation and the areas of insulation within the joint. The linear loss is to be estimated for all the sides of the window. If the same insulation is used in all sides of the windows, then the linear loss will be equal for all the window sides. This also ap-plies, if the roof construction and the insulation next to the window are slightly modified.

In case the transmission coefficient for the skylight or the roof window is estimated without taken into account the heat loss through the side of the frames, the transmission coefficient should be in-creased according to the heat loss through the side of the frames. The heat loss through the frame side of the windows is determined by using the values in table 6.12.4 measuring the frame height from upper side of the joint to the outer surface of the glassing, se figure 6.12.3.

Table 6.12.4 – Linear loss Ψs in W/m K for joints around skylight and roof windows

Thickness of insulation in joint Height of joint mm

None 25 mm 50 mm 75 mm

0 0,05 0,03 0,02 (0,01) 50 0,15 0,08 0,05 0,04 100 0,25 0,13 0,08 0,06 200 0,45 0,23 0,14 0,11 300 0,65 0,33 0,20 0,16

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a) Skylight b) Roof window

Figure 6.12.3 – Measurement when deciding height of the joints around skylight and roof windows and insulation thickness within the joints. The figure furthermore shows the measurement when de-termining the height of the frame for skylight and roof windows in cases where the heat loss through

the side of the frames is neglected. 6.13 Foundations

6.13.1 Foundations for external walls at ground supported floors The linear loss Ψf for external wall foundations at ground supported floors is estimated by table 6.13.1-6 and figure 6.13.1-6.13.7:

Table 6.13.1 is used in connection with frame walls and corresponding light walls

Table 6.13.2a, b and c are used in connection with cavity walls as well as for other outer walls with back wall in concrete, bricks, lightweight concrete or the like

Table 6.13.3 is used in connection with concrete-sandwich elements

Table 6.13.4 is used in connection with a concrete plate that is casted into or above the foundation

Table 6.13.5 is used in connection with foundation for industrial construction work

Table 6.13.6a is used in connection with foundation below doors and window-fronts at terrain deck.

The attached sketches of the different foundation types have been listed at the different tables either in the headline (if there only is a figure, which we refer to) or in the footnotes (if there are several figures, which we refer to).

For constructions with equivalent structure but different insulation thickness and heat flow capability, in-terpolation in the tables is permitted. The values shown in the tables provide:

Terrain level is at most 30 cm lower than floor level. The width of the foundation is no more than 2 cm less than the thickness of the external walls The external wall covers the whole top part of the foundation. Where the foundation is carried out with

insulation in the centre, it is adequate to cover the centre insulation and 20mm on each side of it. The floor concrete’s thickness is at most 12 cm. The rear wall’s thickness is for bricks at most 11 cm, and for light weight concrete and concrete at most

12 cm. For other construction types or other location of ground or floor the linear transmission coefficient is to

be calculated as shown in annex D.

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Table 6.13.1 – Linear loss Ψf in W/mK for external wall foundations at ground supported floors in connection with frame walls and equivalent lightweight walls (see fig. 6.13.1 and 6.13.2 below) Foundation Insulation above concrete plate: None 75 mmG)

U-value for terrain deck: 0,30 0,20 0,10 0,20 0,10 Concrete1) No insulation 15 mm cold bridge interruptionR)

0,75 0,70 0,66 0,21 0,24 0,44 0,37 0,28 0,17 0,16

Light clinker concrete2) upper 40 cm 0,31 0,24 0,17 0,14 0,12 Light clinker concrete3) upper 40 cm, central insulatedM1) 0,26 0,19 0,14 0,10 0,08 Light clinker concrete3) upper 60 cm, 40 cm central insulatedM1) 0,23 0,17 0,13 0,09 0,08 Light clinker concrete4) upper 40 cm, central insulatedM2) 0,23 0,17 0,12 0,09 0,07 Light clinker concrete5) upper 40 cm, central insulatedM3) 0,22 0,15 0,11 0,09 0,06 Light clinker concrete6) upper 40 cm, central insulatedM4) 0,19 0,13 0,10 0,08 0,06 1) Plain concrete with thermal conductivity of 2,0 W/mK 2) Light clinker concrete with thermal conductivity of 0,25 W/mK and width on 19 cm. 3) Light clinker concrete with thermal conductivity of 0,25 W/mK and width on 33 cm. 4) Light clinker concrete with thermal conductivity of 0,25 W/mK and width on 39 cm. 5) Light clinker concrete with thermal conductivity of 0,25 W/mK and width on 49 cm. 6) Light clinker concrete with thermal conductivity of 0,25 W/mK and width on 74 cm. G) 15 mm insulation with thermal conductivity at most 0,04 W/mK R) 75 mm insulation with thermal conductivity at most 0,04 W/mK along terrain deck’s edge, see fig. 6.13.2 sketch a).M1) 75 mm insulation with thermal conductivity at most 0,04 W/mK at least 40 cm down, see figure 6.13.1 sketch c M2) 150 mm insulation with thermal conductivity at most 0,04 W/mK at least 40 cm down, see figure 6.13.1 sketch c M3) 250 mm insulation with thermal conductivity at most 0,04 W/mK at least 40 cm down, see figure 6.13.1 sketch c M4) 500 mm insulation with thermal conductivity at most 0,04 W/mK at least 40 cm down, see figure 6.13.1 sketch c

Table 6.13.2 a – The linear loss Ψf in W/m K for external wall with inner leaf of lightweight concrete4)

(see figure 6.13.1 and 6.13.2 below)

Foundation Insulation above concrete plate: None 75 mmG) U-value for terrain deck: 0,30 0,20 0,10 0,20 0,10

Concrete1) No insulation 15 mm cold bridge interruptionR)

0,77 0,73 0,71 0,30 0,33 0,57 0,51 0,45 0,28 0,27

Light clinker concrete2) upper 40 cmR) 0,30 0,23 0,18 0,16 0,14 Light clinker concrete3) upper 40 cm, central insulatedM1) 0,24 0,17 0,13 0,13 0,10 Light clinker concrete3) upper 60 cm, 40 cm central insulatedM1) 0,21 0,15 0,11 0,12 0,09 Light clinker concrete6) upper 40 cm, central insulatedM2) 0,22 0,15 0,12 0,13 0,09 Light clinker concrete7) upper 40 cm, central insulatedM3) 0,19 0,13 0,10 0,11 0,08 1) Plain concrete with thermal conductivity of 2,0 W/mK 2) Light clinker concrete with thermal conductivity of 0,25 W/mK and width on 35 cm. 3) Light clinker concrete with thermal conductivity of 0,25 W/mK and width on 39 cm. 4) Light clinker concrete with thermal conductivity of 0,30 W/mK 5) Is also valid for light weight concrete with thermal conductivity of 0,70 W/mK 6) Light clinker concrete with thermal conductivity of 0,25 W/mK and width on 49 cm. 7) Light clinker concrete with thermal conductivity of 0,25 W/mK and width on 74 cm. G) Insulation with thermal conductivity at most 0,04 W/mK R) 15 mm insulation with thermal conductivity at most 0,04 W/mK along terrain deck’s edge, see fig. 6.13.2 sketch a).M1) 150 mm insulation with thermal conductivity at most 0,04 W/mK at least 40 cm down, see figure 6.13.1 sketch c M2) 250 mm insulation with thermal conductivity at most 0,04 W/mK at least 40 cm down, see figure 6.13.1 sketch c M3) 500 mm insulation with thermal conductivity at most 0,04 W/mK at least 40 cm down, see figure 6.13.1 sketch c

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Table 6.13.2b – The linear loss Ψf in W/mK for external wall with inner leaf of brickwork5) (see figure 6.13.1 and 6.13.2 below

Foundation Insulation above concrete plate: None 75 mmG)

U-value for terrain deck: 0,30 0,20 0,10 0,20 0,10 Concrete1) No insulation 15 mm cold bridge interruptionR)

0,83 0,79 0,77 0,39 0,41 0,66 0,61 0,55 0,37 0,37

Light clinker concrete2) upper 40 cm R) 0,31 0,24 0,19 0,19 0,16 Light clinker concrete3) upper 40 cm, central insulatedM1) 0,24 0,17 0,13 0,14 0,11 Light clinker concrete3) upper 60 cm, 40 cm central insulatedM1) 0,21 0,15 0,11 0,14 0,10 Light clinker concrete6) upper 40 cm, central insulatedM2) 0,22 0,16 0,12 0,14 0,10 Light clinker concrete7) upper 40 cm, central insulatedM3) 0,19 0,13 0,10 0,11 0,08 1) Plain concrete with thermal conductivity of 2,0 W/mK 2) Light clinker concrete with thermal conductivity of 0,25 W/mK and width on 35 cm. 3) Light clinker concrete with thermal conductivity of 0,25 W/mK and width on 39 cm. 4) Light clinker concrete with thermal conductivity of 0,30 W/mK 5) Is also valid for light weight concrete with thermal conductivity of 0,70 W/mK 6) Light clinker concrete with thermal conductivity of 0,25 W/mK and width on 49 cm. 7) Light clinker concrete with thermal conductivity of 0,25 W/mK and width on 74 cm. G) Insulation with thermal conductivity at most 0,04 W/mK R) 15 mm insulation with thermal conductivity at most 0,04 W/mK along terrain deck’s edge, see fig. 6.13.2 sketch a).M1) 150 mm insulation with thermal conductivity at most 0,04 W/mK at least 40 cm down, see figure 6.13.1 sketch c M2) 250 mm insulation with thermal conductivity at most 0,04 W/mK at least 40 cm down, see figure 6.13.1 sketch c M3) 500 mm insulation with thermal conductivity at most 0,04 W/mK at least 40 cm down, see figure 6.13.1 sketch c

Table 6.13.2c – The linear loss Ψf in W/mK for external wall with inner leaf of concrete (see figure 6.13.1 and 6.13.2 below

Foundation Insulation above concrete plate: None 75 mmG)

U-value for terrain deck: 0,30 0,20 0,10 0,20 0,10 Concrete1) No insulation 15 mm cold bridge interruptionR)

0,95 0,91 0,88 0,58 0,60 0,82 0,77 0,72 0,57 0,57

Light clinker concrete2) upper 40 cm R) 0,32 0,26 0,21 0,23 0,19 Light clinker concrete3) upper 40 cm, central insulatedM1) 0,24 0,17 0,13 0,16 0,12 Light clinker concrete3) upper 60 cm, 40 cm central insulatedM1) 0,22 0,15 0,12 0,16 0,11 Light clinker concrete6) upper 40 cm, central insulatedM2) 0,23 0,16 0,12 0,16 0,11 Light clinker concrete7) upper 40 cm, central insulatedM3) 0,19 0,13 0,10 0,14 0,09 1) Plain concrete with thermal conductivity of 2,0 W/mK 2) Light clinker concrete with thermal conductivity of 0,25 W/mK and width on 35 cm. 3) Light clinker concrete with thermal conductivity of 0,25 W/mK and width on 39 cm. 4) Light clinker concrete with thermal conductivity of 0,30 W/mK 5) Is also valid for light weight concrete with thermal conductivity of 0,70 W/mK 6) Light clinker concrete with thermal conductivity of 0,25 W/mK and width on 49 cm. 7) Light clinker concrete with thermal conductivity of 0,25 W/mK and width on 74 cm. G) Insulation with thermal conductivity at most 0,04 W/mK R) 15 mm insulation with thermal conductivity at most 0,04 W/mK along terrain deck’s edge, see fig. 6.13.2 sketch a).M1) 150 mm insulation with thermal conductivity at most 0,04 W/mK at least 40 cm down, see figure 6.13.1 sketch c M2) 250 mm insulation with thermal conductivity at most 0,04 W/mK at least 40 cm down, see figure 6.13.1 sketch c M3) 500 mm insulation with thermal conductivity at most 0,04 W/mK at least 40 cm down, see figure 6.13.1 sketch c

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Table 6.13.3 – Linear loss ψf W/m K for external wall foundations at ground supported floors in connection with concrete sandwich elements )see figure 6.13.1 and 6.13.2 below).

Foundation Insulation above concrete plate:1) None 75 mmG)

U-value for terrain deck: 0,30 0,20 0,10 0,20 0,10 Concrete 100 mm external insulationU) do. and 15 mm cold bridge interruptionR)

0,34 0,33 0,33 0,28 0,28 0,31 0,30 0,29 0,28 0,28

Concrete 150 mm external insulationU) do. and 15 mm cold bridge interruptionR)

0,31 0,30 0,30 0,26 0,26 0,29 0,27 0,27 0,26 0,26

Concrete central insulatied 60 cm down (75 mm thicknessM) do. and 15 mm cold bridge interruptionR)

0,45 0,41 0,39 0,31 0,29 0,42 0,37 0,34 0,31 0,29

1) Reinforced concrete with 1 volume-% steel. 2) Light clinker concrete with thermal conductivity of 0,25 W/mK and width on 35 cm. G) Insulation with thermal conductivity at most 0,04 W/mK R) 15 mm insulation with thermal conductivity at most 0,04 W/mK along terrain deck’s edge, see fig. 6.13.2 sketch a).U) External insulation with thermal conductivity at most 0,04 W/mK 90 cm down, see figure 6.13.2 sketch b M) 75 mm insulation with thermal conductivity at most 0,04 W/mK 60 cm down, see figure 6.13.1 sketch d

Figure 6.13.1 – Foundation top designs

Figure 6.13.2 – Insulation around the foundations

a) Cold bridge interruption along the ground

deck’s edge

b) External insulation in connection with

concrete sandwich element

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Table 6.13.4a - The linear loss ψf in W/mK for foundations at terrain deck, where the concrete plate is casted in above the foundation (see figure 6.13.3) Rear wall Light weight concrete,

brick or concrete Light weight

concrete Concrete

Foundation Insulation above concrete plate: U-value for terrain deck:

None 75 mm 75 mm 0,30 0,20 0,10 0,20 0,10 0,20 0,10

Light clinker concrete 40 cm1) 0,30 0,23 0,20 0,15 0,13 0,22 0,18 Light clinker concrete 40 cm1)2) 0,23 0,17 0,13 0,13 0,10 0,19 0,12 Light clinker concrete 60 cm1)3) 0,21 0,15 0,12 0,12 0,09 0,17 0,12 1) Light clinker concrete with thermal conductivity of 0,25 W/mK and width on 39 cm. 2) Central insulation (150 mm) in both courses with thermal conductivity at most 0,04 W/mK. 3) Central insulation (150 mm) in upper 40 cm with thermal conductivity at most 0,04 W/mK.

Figure 6.13.3 – Foundations, where concrete plate is casted in above the foundation

Table 6.13.4b - The linear loss ψf in W/mK for foundations at terrain deck, where the concrete plate is casted into the foundation (see figure 6.13.4) Rear wall Light weight concrete,

brick or concrete Light weight

concrete Concrete

Foundation Insulation above concrete plate: U-value for terrain deck:

None 75 mm 75 mm 0,30 0,20 0,10 0,20 0,10 0,20 0,10

Light clinker concrete 40 cm1)2) 0,26 0,18 0,14 0,14 0,11 0,20 0,14 Light clinker concrete 60 cm1)3) 0,23 0,16 0,13 0,13 0,10 0,18 0,12 1) Light clinker concrete with thermal conductivity of 0,25 W/mK and width on 39 cm. 2) Central insulation (150 mm) in both courses with thermal conductivity at most 0,04 W/mK. 3) Central insulation (150 mm) in upper 40 cm with thermal conductivity at most 0,04 W/mK.

Figure 6.13.4 – Foundations, where concrete plate is casted into the foundation

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Table 6.13.4c - The linear loss ψf in W/mK for foundations at terrain deck, where the concrete plate with knob is casted into the foundation (see figure 6.13.5) Rear wall Light weight concrete,

brick or concrete Light weight

concrete Concrete

Foundation Insulation above concrete plate: U-value for terrain deck:

None 75 mm 75 mm 0,30 0,20 0,10 0,20 0,10 0,20 0,10

Light clinker concrete upper 40 cm1)2) 0,29 0,21 0,17 0,15 0,12 0,22 0,16 Light clinker concrete upper 60 cm1)3) 0,25 0,18 0,14 0,14 0,11 0,20 0,14 1) Light clinker concrete with thermal conductivity of 0,25 W/mK and width on 39 cm. 2) Central insulation (150 mm) in both courses with thermal conductivity at most 0,04 W/mK. 3) Central insulation (150 mm) in upper 40 cm with thermal conductivity at most 0,04 W/mK.

Figure 6.13.5 – Foundations, where concrete plate with knob is casted into the foundation

Table 6.13.5a - The linear loss ψf in W/mK for industrial foundations at terrain deck

(see figure 6.13.6 – see sketch-no. in the table)

Foundation U-value for terrain deck: 0,50 0,30 0,10 See sketch-no.

in fig. 6.13.6 Concrete foundation1) with 75 mm external insulation2) and 20 mm cold bridge interruption between deck and foundationR1)

0,87 0,54 0,47 1

Concrete foundation1) with 150 mm external insulation2) and 20 mm cold bridge interruption between deck and foundationR1)

0,79 0,49 0,43 2

Concrete foundation1) with 75+75 mm central insulation2) and 50 mm cold bridge interruption between deck and foundationR1)

0,79 0,43 0,34 3

Concrete foundation1) with 75+75 mm central insulation2) and light clinker blocks3)

0,71 0,38 0,29 4

Light clinker concrete4) upper 40 cm, central insulated5) 0,66 0,28 0,17 5 Point supported foundation6) 0,66 0,30 0,20 6a and 6b Pile supported foundation7) 0,52 0,43 0,46 7 1) Plain concrete with thermal conductivity of 2,0 W/mK 2) insulation with thermal conductivity of at most 0,04 W/mK. 3) Light clinker concrete with thermal conductivity of 0,25 W/mK and width on 100 mm. 4) Light clinker concrete with thermal conductivity of 0,25 W/mK and width of outer block 100 mm and inside block 150 mm 5) 100 mm insulation with thermal conductivity of at most 0,04 W/mK at least 40 cm down. 6) Section by walls: 370 mm wide foundation with 2 courses 100-mm jambs in light clinker concrete and 170 mm insulation, and 20 mm cold bridge interruption between terrain deck and foundation. Section by columns: 370 mm wide foundation with 2 courses 100-mm-jamb in light clinker concrete and 120 mm insulation. 7) 360 mm wide pile supported foundation with 100 mm insulation on both in- and outside. R1) 20 mm insulation with thermal conductivity at most 0,04 W/mK along the terrain deck’s edge. R2) 50 mm insulation with thermal conductivity at most 0,04 W/mK along the terrain deck’s edge.

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For constructions with corresponding construction, but other insulation thickness and thermal conduc-tivity, interpolation can be made in the table. The values in the table provide: The terrain's surface is at most 30 cm lower than the top side of finished floor. For raised founda-

tions the values can be corrected with table 6.13.5b. The foundation’s width is at most 2 cm smaller than the outer wall's thickness. The outer wall covers the whole top of the foundation. For foundations with central insulation it's

sufficient to cover the central insulation and 20 mm on each side. The floor concrete's thickness is at most 15 cm. The rear wall's thickness is at most 15 cm.

Figure 6.13.6 – Foundations for industrial buildings (Sketch 1 – 5)

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Figure 6.13.6 – Foundations for industrial buildings (sketch 6a+b and 7)

The linear loss coefficient is depending on the foundation’s contact with the outer climate. Therefore it's necessary to correct it for foundations, which distance from terrain to top side of deck is bigger than 30 cm. Table 6.13.5b shows additions in % to foundations’ linear loss coefficient for raised foundations.

Table 6.13.5b – Additions in % to foundation’s linear loss coefficient for raised foundations Distance from terrain to topside of deck

U-value for terrain deck

0,50 W/m2K 0,30 W/m2K 0,10 W/m2K

<=30 cm 0 0 0

45 cm 10 7 5

60 cm 20 15 10

75 cm 25 20 12

>=90 cm 30 22 15

6.13.2 Linear loss coefficients for foundations below doors and windows The linear loss ψf for foundations below doors and windows at terrain deck can be calculated as: Ψf = ψfx + ψk Where Ψfx is the linear loss for foundation below door/window according to table 6.13.6a Ψk is the linear loss for the cold bridge between bottom frame and foundation according to table 6.13.6b.

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Examples of linear loss Ψfx for foundations below doors and windows are shown in table 6.13.6a with matching sketches (1 – 9) of the foundations shown in figure 6.13.7.

Table 6.13.6a – Linear loss Ψfx in W/mK for foundations below doors and windows at terrain deck (see figure 6.13.7 – see sketch no. in the table)

Foundation U-value for terrain deck: 0,30 0,20 0,10 See sketch-no.

in fig. 6.13.7

Concrete1) No insulation 0,89 0,85 0,82 1

Light clinker concrete2) the upper 40 cm

Upper course central insulated with 40 mm M) 0,44 0,37 0,34 2

Both courses central insulated with 40 mm M) 0,38 0,34 0,31 3

Upper course central insulated with 100 mm M) 0,36 0,29 0,26 4

Both courses central insulated with 100 mm M) 0,32 0,25 0,21 5

Upper course central insulated with 40 mm M)D) - 0,22 0,18 6

Both courses central insulated with 40 mm M)D) - 0,22 0,18 7

Upper course central insulated with 100 mm M)D) - 0,17 0,13 8

Both courses central insulated with 100 mm M)D) - 0,16 0,12 9 1) Plain concrete with thermal conductivity of 2,0 W/mK. 2) Light clinker concrete with thermal conductivity of 0,25 W/mK and width of 35 cm. M) Insulation with thermal conductivity of at most 0,04 W/mK. D) 80 mm insulation between concrete slab and light clinker blocks in 2nd course.

Figure 6.13.7 – Sketches of foundations below doors and windows

The linear loss Ψk for joints between foundations and bottom frame are shown in table 6.13.6b. An example of such a joint is shown above in figure 6.13.7 sketch 7.

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Preconditions for the values in the table: Ordinary working outs of bottom frames to windows or doors with opening between frame and bottom frame of at most 10 mm, see figure 6.13.8. Possible furring on the bottom frame in ordinary materials such as wood or plastic with a thermal conductivity of at most 0.3 W/mK.

Table 6.13.6b – Linear loss Ψk in W/mK for the joint foundation and bottom frame Bottom frame Cold bridge insulation below window/door next to floor concrete plate

0 mm 40 mm 100 mm Aluminium 0,11 0,05 0,05 PVC, composite 0,06 0,03 (0,01) Wood, Wood/aluminium 0,06 (0,01) (0,00) For special working outs of foundation or bottom frame, where the values in table 6.13.6b cannot be used, the linear loss should be calculated as shown in annex C.3.

Figure 6.13.8 – Example of window/door with opening “a” between frame and bottom frame of more than 10 mm, which causes, that the cavity cannot be considered as light ventilated cavity, which

means that the linear loss will be increased considerably.

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6.13.3 Basement outer wall foundations Examples of the linear loss Ψf for basement outer wall foundations are shown in table 6.13.7a and 6.13.7b with

sketches to match of the foundations. For basement outer walls deeper than 2 m the value is used for 2 m. For other constructions the linear loss can be calculated as described in annex D. Figure 6.13.9-Sketch of foundation

Figure 6.13.10-Sketch of foundation

Table 6.13.7a – The linear loss Ψf in W/mK for basement outer wall foundations. Basement wall in concrete1)

Placing of concrete floor

Soil covering d (m)

Thickness of inside wall insulation2)3)

0 mm 75 mm

Raised 40 cm 1,0 2,0

0,35 0,34

0,26 0,24

Raised 30 cm 1,0 2,0

0,36 0,36

0,27 0,25

Raised 20 cm 1,0 2,0

0,38 0,37

0,29 0,26

Raised 10 cm 1,0 2,0

0,41 0,40

0,31 0,27

In level with con-crete foundation

1,0 2,0

0,43 0,42

0,32 0,28

1) Concrete with thermal conductivity of 2,0 W/mK. 2) Insulation with thermal conductivity of at most 0,04 W/mK. 3) In consideration of moisture at most half of the wall’s total insula- tion should be placed inside.

Table 6.13.7b – The linear loss Ψf in W/mK for basement outer wall foundations. Basement wall in light clinker blocks4)

Placing of concrete floor

Soil covering d (m)

Thickness of inside wall insulation2)3)

0 mm 75 mm

Raised 40 cm 1,0 2,0

0,14 0,13

0,13 0,13

Raised 30 cm 1,0 2,0

0,16 0,15

0,14 0,13

Raised 20 cm 1,0 2,0

0,19 0,17

0,16 0,15

Raised 10 cm 1,0 2,0

0,25 0,23

0,21 0,20

In level with con-crete foundation

1,0 2,0

0,36 0,32

0,31 0,29

2) Insulation with thermal conductivity of at most 0,04 W/mK. 3) In consideration of moisture at most half of the wall’s total insulation should be placed inside. 4) Light clinker concrete with thermal conductivity of 0,28 W/mK.

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6.14 Thermal bridges at corners Corner connections (e.g. wall/ceiling and wall/wall) cause a linear loss, when the two constructions, which are included in the connection detail, create an angle in relation to each other and thus a thermal bridge. The linear loss depends on whether the corner is outwards- or inwardly (see fig. 3.6.2). In an outward corner there will with uninterrupted insulation be a negative linear loss, which gives a deduction in the heat loss because of the measurement with external measures at the area statement. A negative linear loss gives a deduction to the heat loss. If the insulation is not through-going, a positive linear loss can in some cases occur in outward corners depending on insulation thicknesses and construction working outs. At inward corners there is a positive linear loss both at interrupted and uninterrupted insulation. It can be deselected to make a detailed correction for the linear loss in corners, if it is calculated on the safe side. It can be considered to be on the safe side not to include the linear loss from all corner connections, if the insulation in the corners is uninterrupted. If it is chosen to include from corner connections, there always have to be included both positive and negative linear losses. Thermal bridges at corners are calculated according to annex M, where examples also are shown.

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7 Heat flow resistance and thermal conductivity of materials 7.1 Introduction

The calculation of transmission coefficients is based on the heat flow resistance R in m2K/W and the thermal conductivity λ in W/mK for the materials used in the constructions.

7.2 Basis for determination of heat flow resistance and thermal conductivity

7.2.1 Declared values

The following declared values are applied:

For products with a CE-mark: The declared values are set according to the relevant product standard or European technical approv-als. For other products: The declared values are set by procedures; conform to those used for CE-marked products. These pro-cedures are shown in chapter 4.2.1 of the product standards for manufactured heat insulation products DS/EN 13162 – DS/EN 13171 and the Annex A in DS/EN 13172 For granulated products: The procedures in DS/EN 14063-1 and prEN 14063-2 (Extruded clay) or prEN14064-1 and DS/EN 14064-2(Mineral wool) as well as DS/EN 13172 are used. Of the above mentioned standards the on closest to the product to declare is chosen. In Annex D of DS/EN 13162 and in Annex D of DS/EN 13171 as well as in Annex C of DS/EN 13170, there are examples showing methods and rules of rounding off. Control rules, conform to the regulations for CE-marked products, are shown in Annex E. Declared values for heat flow resistance and conductivity in the manufacturer literature and on the prod-ucts must be attended with a reference to: “DS 418, 7. version, 2011”.

7.2.2 Design values

Design values are set based on the products declared values, according to DS/EN 10456 or directly by: Annex F. Design values for brick, concrete and other building materials DS/EN 1745

By determination of R and λ it is considered that, products build into constructions, have different mois-ture content than by laboratory measurements. In addition the middle temperature for the build in product, may deviate from 10° C, which applies by la-boratory measurements. Analyses of insulation products moisture conditions in ordinary Climate Screen constructions shows, that correction to the declared value only are necessary when the product is used towards the soil. However, it must always be considered whether the combination of product, construction and influence makes it necessary to correct the declared values in order to achieve the correct design value. For use towards the soil, the design value of insulation products can normally be calculated by DS/EN ISO 10456, with Fm = 1.2. This applies for extruded polystyrene, extruded clay and mineral wool. (λ = λdeclared * Fm ) Design values for materials and reflective surfaces are determined by calculation or measuring according to 6.4.4.

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As the design value is depending on the insulation's, horizontal or vertical and the heat flow’s direction, the product is to be labelled with the measured heat flow resistance and the matching about orientation and heat flow direction, as well as a reference to "DS 418, 7. edition, 2011. The test piece have to be representative for the construction, the reflective insulation has been intended used in. It is build up and orientated as the construction (vertical, horizontal or after the heat flow direction), and measured at a mean temperature at 10 °C. In Annex G, a list of design values for use in calculation of existing constructions in connection with rebuilding and renovation, are given.

7.2.3 Special provisions

Thermal insulation material with soil contact

By this means insulation material mounted externally on basement walls as well as foundations. It is provid-ed, that the constructions are kept dry by implementing drainage or other precautions. For terrain deck and basement floors, where the insulation material is placed between the concrete and a layer of gravel of at least 75 mm thickness or equivalent material with grain size of at least 4 mm, the table values applicable for dry material can be used. In cases where the capillary breaking gravel layer is less than 75 mm the table values applicable for “with soil contact” should be used. It is the thickness of the compressed insula-tion layer that applies.

Brickwork constructions The listed values of design heat transmission capability for the brickwork as a whole should be applied, since the contribution of the joints are included in the values. The design heat transmission capability is applicable for brick work of bricks in normal format without regards to pattern and bond as well as brick-work of light concrete blocks without regards to deviation from the listed block format and joint sizes. Usu-ally the type of the applied mortar is neglected as well. However, for lightweight concrete block work the

heat flow resistance may be increased by 0.15 m2 K/W if all the joints are provided with a 4 x 1 cm strip of mineral wool or polystyrene.

The moisture content for materials used external and internal The moisture content is determined by 23° C and 85% RF and 50% RF respectively. Design conductivity is calculated according to DS/EN ISO 10456.

Brickwork and light weight concrete Where the values distinguish between internal and external application of a material, it should be taken in-to account the heat transmission capability for internal application, if the material is used in partition walls, storey partition and crawl space deck as well as the inner section of combined external walls and roofs. The heat transmission capability for external application of materials apply, where the ma-terial is to be found in the outer section of combined outer walls, roofs and terrain decks. For massive external walls of brickwork made of bricks in normal format, the external heat transmission capability should be applied for the façade layers and the in-ternal heat transmission capability for the rest of the wall. For cavity walls made of brickwork the external values apply for the outer leaf and the internal values for the inner leaf. For massive external walls of light-weight concrete the external values apply for 100 mm of the thickness of the wall and the internal values apply for the rest of the wall. The heat transmission capability of different materials is depending on the temperature, why the listed prac-tical values apply for temperatures normally found in building constructions. The values are not to be ap-plied for calculation of pipe insulation, cold store insulation, and chimney or stove insulation.

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Annex A (normative)

Correction of transmissions coefficients

A.1 General

Transmissions coefficients calculated according to this standard must be corrected for the effect of: - Cracks in the insulation layer - Ties and similar mechanical fixations - Precipitation on “upside down” roof The resulting transmission coefficient U is achieved by adding the correction ∆U:

U = U’ + ∆U

Where

∆U = ∆Ug + ∆Uf + ∆Ur

where ∆Ug is a correction for air-cracks in the insulation layer ∆Uf is a correction for ties and similar mechanical fixations ∆Ur is a correction for precipitation on “upside down” roof

A.2 Correction for air-cracks in the insulation layer

The correction ∆Ug must be adjusted for the heat flow resistance of the insulation relatively to the total heat flow resistance of the construction:

where

∆U” is the correction for air-cracks in the insulation layer. ∆U’’ is found in table A.1. Ri is the heat flow resistance of the insulation layer RT is the total heat flow resistance of the construction.

Table A.1 – Correction for air-cracks in the insulation layer

Level ∆U”

W/m2K Description

0 0,00 No air-cracks across the insulation layer 1 0,01 Possibility for air-cracks across the insulation layer

No air circulation on the warm side of the insulation layer 2 0,04 Possibility for air-cracks across the insulation layer

Possibility for air circulation on the warm side of the insulation layer

A.2.1 Air-cracks across the insulation layer It is presumed that no increases of the heat loss perpendicular to the insulation layer is appears, if the in-sulation is carried out as two or more layers with displaced joints, or if the insulation is loos fillings and the cavity is totally filled.

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If the insulation is carried out with slabs in only one layer without grooved joints, or the insulation regularly are penetrated by e.g. beams, rafters, or wall-ties, the risk of air-cracks across the insulation layer is pre-sent.

The increased heat loss caused by air-cracks, with a width of more than 5 mm, across the insulation layer must be included in the calculations.

A.2.2 Air circulation on the warm side of the insulation It is presumed that no risk of air circulation on the warm side of the insulation appears if the cavity is totally filled, or if the insulation lies tightly against the warm side. The same applies if a soft insulation rests, with its own weight, on the warm side in closed constructions, attics or similar.

There is risk of air circulation on the warm side of the insulation, where a insulation material not lies tightly against a plane surface or where a hard insulation material is squeezed in between beams, rafters, trusses of battens. The same applies if there is no rigid material on the warm side of the insulation.

Air circulation on the warm side of the insulation only has consequences if there is connection the cold side of the insulation or to the open.

A.2.3 Examples Level 0 - Ceiling insulation with two layers of insulation, where the top layer is laid with displaced joints across

an insulation layer between the ceiling struts of the truss. - Soft insulation in a cavity wall with cavity ties, wedged against a plane surface on the warm side - Roof insulation in to layers with displaced joints - Insulation with displaced joints between two layers of crossing studs, beams or battens - Roof-, external façade- and terrain-insulation in one layer with grooved joints or one layer, where

length-, width-, and angle-tolerances and stability of dimension provides that cracks larger than 5mm will not occur.

- Granulated insulation

Level 1 - Soft ceiling insulation on a hard, smooth board, between ceiling struts of trusses - Soft ceiling insulation between ceiling struts of trusses, laid on DPM supported by battens - Soft insulation between rafters, studs, beams or trusses, wedged against a hard, plane surface on the

warm side - Soft insulation in a cavity wall with cavity ties, wedged against brickwork with exactly filled joints on

the warm side.

Level 2 - Hard insulation between, beams, studs, rafters or trusses, regardless of the layer on the warm side - Insulation between, beams, studs, rafters or trusses not wedged against the warm side - Insulation between, beams, studs, rafters or trusses only covered by e.g. DPM or cardboard on the

warm side - Insulation in a cavity wall with cavity ties, brickwork with un-, or overfilled joints on the warm side.

A.3 Correction for ties

If ties or similar mechanical fixations go through the insulation the correction is:

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DS 418:2011

where is a coefficient; for this annex = 0,8

is the thermal conductivity for the wall-tie in W/mK nf is the number of ties per m2 Af is cross sectional area of the tie in m2 d1 is the thickness of the insulation layer, that contains ties, in m R1 is the heat flow resistance of the insulation layer with ties in m2K/W RT is the construction’s total heat flow resistance in m2K/W.

Correction for ties or similar mechanical fixations is not needed in the following cases: - ties through a non-insulated cavity - ties between brickwork and timber-frame - if the heat flow resistance of the tie of similar mechanical fixation or a part of it is less than 1 W/mK - the correction for the tie is less than 0.005 W/m2K stated with ( ) in table A.2.

Table A.2 – Tie correction ∆Uf in W/m2K for common ties used in cavity walls

Type of tie Diameter mm 8 ties per m2 4 ties per m2

Insulation thickness m Insulation thickness m

0,1 0,125 0,15 0,2 0,1 0,125 0,15 0,2

Plastic 0 0 0 0 0 0 0 0

Stainless steel 3 (0,004) (0,004) (0,003) (0,003) (0,002) (0,002) (0,002) (0,001)

Stainless steel 4 0,008 0,007 0,006 0,005 (0,004) (0,003) (0,003) (0,002)

Stainless steel 5,5 0,014 0,013 0,011 0,009 0,007 0,006 0,006 0,005

Bronze 3 0,016 0,014 0,013 0,011 0,008 0,007 0,006 0,005

Bronze 4 0,029 0,026 0,023 0,019 0,014 0,013 0,011 0,009

Bronze 5 0,045 0,040 0,036 0,030 0,022 0,020 0,018 0,015

Zincked iron 8 0,097 0,087 0,078 0,064 0,049 0,043 0,039 0,032

The rules in this section (A3) can’t be used, if both ends of the tie or the similar mechanical fixation are in contact with metallic cover materials. In these cases the methods of DS/EN ISO 10211 can be applied.

A.4 Correction for rain on “upside down” roof

A.4.1 Generally The heat flow resistance for “upside down” roof is to be corrected for the effect of rainwater that runs between the insulation and the roof's watertight membrane. The rules in A.4 are valid only for insulation carried out with extruded polystyrene (XPS). Are other insulation products used, the effect of rainwater that runs between the insulation and the roof's watertight membrane, and the insulating's moisture uptake have to be documented.

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A.4.2 Correction of the roof construction’s transmission coefficient for the rain amount, that runs be- tween the insulation and the watertight membrane

where Symbol Size Unit

f Factor for that part of the overall rain amount which go through the con-nections in the insulation to the watertight membrane

None

p Average rainfall in the heating season mm/day

x Factor for extra heat loss caused by rainwater, which runs on the water-tight membrane

Wday/m²·K·mm

Rl Heat flow resistance of XPS insulation across the watertight membrane m²·K/W

RT The construction's complete heat flow resistance m²·K/W

Ur

Correction of the roof construction's calculated transmission coefficient for the extra heat loss caused by the rain amount, which goes through the connections in the XPS insulation to the watertight membrane

W/m²K

Ur is calculated with two decimals. Ur smaller than 0,01 is like serrow. The construction of “upside down” roof, that is considered to give the largest Ur, is a one layer insulation with open covering. For other constructions, that reduce the amount of rainwater which reaches the watertight membrane, can lower values for fx be used, assuming that the reduction can be documented. A.4.3 Correction of the thermal conductivity The XPS insulation's thermal conductivity should be corrected for moisture uptake by diffusion with relation to DS/EN ISO 10456. For diffusion-open coverings as stone layers and corresponding is the moisture uptake in XPS without im-portance.

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DS 418:2011

Annex B (normative)

Determination of linear loss for thermal bridges in constructions By the determination of the linear loss k for thermal bridges in constructions attention is paid to the two-dimensional heat flows in the thermal bridge and in the construction up to the thermal bridge. The line loss k in W/mK for a thermal bridge is determined by 1. calculation of the overall two-dimensional heat flow through the thermal bridge as well as 1.0 m of the construction up at the thermal bridge, watch figure B.1 2. deduct the corresponding one dimensional heat flow through the thermal bridge and the construction 3. divide by the difference between room- and outdoor-temperature. The heat flows are determined per meter thermal bridge, see section 3.7. At the calculation heat flows in the thermal bridge's longitudinal direction are ignored as well as heat exchange through the adiabatic boundary surface determined of a cut in the construction 1.0 m from the thermal bridge and a corresponding cut in the thermal bridge's centre line. For brick filling in and ribs around holes to e.g. windows and doors lies the last ad-iabatic boundary surface instead, where the construction ends. At the calculations is normally applied an out-door-temperature at 0 °C and a room temperature of 20 °C. The overall two-dimensional heat flow through the thermal bridge and 1.0 m of the construction up to the ther-mal bridge are determined by calculating the overall heat flow through the inside surfaces in W/m. The calculation can be carried out with a simulation program that uses numerical methods for deciding temper-ature conditions and heat flows in the construction. At the calculation the cross section is split up in figure B.1 in smaller elements with identical material data. Jf. DS/EN ISO 10211 the elements are to be so small that further under-division will not change the calculation result considerably.

Figure B1 – Calculation model for determination of linear loss for thermal bridge in a construction

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DS 418:2011

Annex C

(normative) Determination of linear loss for connections around windows and doors

C1 Windows and doors in the façade mounted in straight groove

By the determination of the line loss sa for connections around windows and doors attention is paid to the heat flow that the connection causes, including two-dimensional heat flows in the window or the door as well as in the remaining construction up to the connection. The linear loss sa in W/mK for a connection is determined by 1. calculation of the overall two-dimensional heat flow through the connection as well as 0.2 m of the pane or

the door plate and at least 1.0 m of the remaining construction up at the connection, see figure C.1 2. insert an adiabatic boundary, where the connection around the window or the door is adjacent to the re-

maining construction 3. calculate the corresponding overall two-dimensional heat flow through respectively the window or the door

and the remaining construction 4. subtract those last calculated heat flows from the overall two-dimensional heat flow 5. divide by the difference between room- and outdoor-temperature. The heat flows are determined per meter joint, see section 3.7. At the calculation are ignored heat flows in the connection's longitudinal direction as well as heat exchange through the adiabatic boundary determined of a cut 0.2 m inside the pane or the door plate and a corresponding cut in the remaining construction at least 1.0 m from the connection. The calculations are carried out otherwise like pointed out in annex B. Figure C.1 – Calculation model for determination of linear loss for connection around window and door C.2 Windows and doors in the front mounted in a displaced groove By the determination of the linear loss sa for connections, where windows and doors are mounted in a dis-placed groove, sa express the combined effect of the connection between window and wall as well as the in-sulation on the window frame. The heat flow that the connection causes should be considered, including the two-dimensional heat flow in the window or doors as well as in the remaining construction up to the connection.

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The linear loss sa in W/mK for a connection is determined at: 1. to calculate the overall two-dimensional heat flow through the connection as well as 0.2 m of the pane or

the door plate and at least 1.0 m of the remaining construction up at the connection, see figure C.2 2. to calculate the overall two-dimensional heat flow through the window or the door separately without a

deck plate, insulation or the like 3. to calculate the overall two-dimensional heat flow through the outer wall separately 4. to subtract the last calculated heat flow (point 2 and 3) from the overall two-dimensional heat flow (point 1).

Window/door is counted as external frame measure, while the wall is counted as incl. a possible caulking joint, watch a figure C.2.

Figure C.2 – Calculation model at determination of linear loss for connection around window or door or

door mounted in displaced groove (displacement of rear wall) Example: For a construction with a window mounted in a displaced groove, equivalent to figure C.2, there has with an appropriate calculation program been determined heat flows like shown in table C.1, where also geometrical data appear. Mounting of windows and doors in a displaced groove corresponds to a displacement of the outer wall's inside or external part in relation to the window (see figure 6.12.1). The Danish tradition – with out-going and rather near the edge placed windows - means that it will be most natural with a displacement of the rear wall, but dis-placement of the front wall will typically give less linear loss, since the window frame is placed next to insulation in the wall, which is heat-technical optimally. There are other things being equal two positive energy wise effects concerning traditional mounting in a straight groove: 1. The linear loss in the connection is decreased, and the heat loss through the window is reduced. 2. Mounting in a displaced groove can lead to some of the same advantages as more narrow frame/casing

profiles, as a higher solar energy- and daylight transmission can be obtained in relation to the inside wall hole, and it may also be valuable concerning fastening and jointing of windows as well as in architectural connection.

Typical is it not the totally great energy wise profit that can be obtained at mounting in a displaced groove.

Therefore it can normally not be worth it to make mounting in a displaced groove solely from an energy wise point of view.

Tabel C.1 - Example of calculated heat loss coefficients and geometrical data

Utotal 0,4783 W/m2K Uwindow 1,7617 W/m2K Uwall 0,140 W/m2K ltotal 1,256 m lwall (incl. external joint) 1,000 m lwindow 0,256 m

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DS 418:2011

The linear loss coefficient sa for the connection is determined from the following formula:

sa =Utotal • ltotal – Uwall • lwall – Uwindow • lwindow W/mK Are the numbers above entered, it is: sa = 0,4783 • 1,256 – 0,140 • 1,000 – 1,7167 • 0,256 = 0,01 W/mK Utotal is the total two-dimensional heat flow through the connection as well as 0.2 m of the pane and 1.0 m of the remaining construction up to the connection (incl. external joint). Uwindow is the heat flow through the win-dow, exclusive of deck plate, insulation or the like, while Uwall is the heat flow in a normal section in the outer wall.

C.3 Windows and doors at foundation With a numerical calculation program there can be built up a two-dimensional calculation model of the connec-tion detail (see figure C.3). In this context it's important that the frame/casing profile is modeled correctly, that is both geometrical and material-related. Stationary conditions, can be assumed, when the linear loss between the bottom frame and the foundation - at a typical foundation solution - only poorly is influenced by the soil vol-ume’s dynamic influence. Judging from the model you can with the program calculate the linear loss k equivalent to the extra heat flow via bottom frame and down into the foundation. The calculation model should include: 1. Bottom frame and framework incl. 0.2 m of panel or pane 2. The upper 0.4 m of the foundation 3. The innermost 0.7 m of the terrain deck reckoned from the foundation’s outside 4. The terrain deck reckoned from finished floor to the underside of the lowest insulation layer 5. The outside of the foundation is reckoned as influenced of the external-climate regardless of the terrain's level. Constant indoor- and outdoor-temperature is anticipated on respectively 20 ˚C and 0 ˚C. Heat flows in the foundation’s longitudinal direction are ignored.

Figure C.3 – Calculation model at determination of the linear loss k for windows and doors at founda-

tion (the bottom frame’s profile can be different from shown in figure) Calculation method With the calculation program is determined the linear loss k in W/mK for windows and doors at foundation by: 1. calculate the overall two-dimensional heat flow through the inside surfaces, see figure C.3 2. enclose an adiabatic boundary surface, where the window/the door is adjacent to the remaining construc-

tion 3. calculate the corresponding overall two-dimensional heat flow through respectively the window or the door

and the remaining construction (heat flows through the inside surfaces) 4. deduct the last calculated heat flows from the overall two-dimensional heat flow

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DS 418:2011

5. divide by the difference between room- and outdoor-temperature. Example It is desirable that a calculation of the linear loss for the connection between a door of PVC profiles and a foun-dation with light clinker concrete in the upper 0.4 m as well as 40 mm of thermal bridge insulation. The terrain deck consists of 120 mm concrete, 150 mm light-clinker, of which the lowest 75 mm are reckoned as capillary breaking. Starting from the model in a figure C.3 is built up a model of the connection between door, foundation and ter-rain deck in a numerical calculation program for the actual example. The model is shown on the left side of fig-ure C.4. After this the program can calculate the heat flow through the inside boundary surface. The heat flow through respectively door and foundation/terrain deck is calculated subsequently by enclosing an adiabatic boundary surface between door and foundation/terrain deck. Alternatively the model can be split up into two models, that are calculated separately; one model with the door profile and one model with foundation/terrain deck like shown in a figure C.4. At the last mentioned method the underside of the door profile and the top side of the foundation next to the area, where the door profile before was placed, have an adiabatic edge requirement. The linear loss k is determined after this by subtracting the last calculated heat flows from the overall two-dimensional heat flow and dividing by 20˚C, equivalent to the temperature difference between outdoor and in-side (see a figure C.4). Joined model Door profile Foundation/Terrain deck Linear loss k

Figure C.4 – Calculation model for determination of the linear loss k for the joint between bottom frame and foundation (the numbers are for the actual model, and they are only shown to illustrate the practice).

C.4 Skylights and roof windows By the determination of the linear loss sa for connections around Skylights and roof windows there is consid-ered the heat flow that the connection causes, including two-dimensional heat flows in the window as well as in the roof construction up to the connection. The line loss sa in W/mK for a connection is determined by: 1. calculate the overall two-dimensional heat flow through the connection as well as 0.2 m of the pane and at least 0.5 m of the roof construction up at the connection, see figure C.5. 2. calculate the one dimensional heat flow through the roof construction for a typical section in the construc-tion between possible rafters by enclosing further one adiabatic boundary surface in the roof construction in the above established model 3. calculate the heat flow through possible rafters in the roof construction including both one- and two-dimensional effects by first calculating the overall heat loss and from that deduct the one dimensional heat flow calculated above, see figure C.6 4. calculate the heat flow through the window with edge requirements as shown on a figure C.7

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5. deduct the calculated heat flows through a roof construction, through a possible rafter and through the win-dow from the overall two-dimensional heat flow 6. divide by the difference between room- and outdoor-temperature. The model of a given construction part, e.g. the roof construction between the rafters or the window itself, is to be identical at all the calculations. The heat flows are determined per meter connection, see section 3.7. At the calculation is ignored the heat flows in the connection's longitudinal direction as well as heat exchange through the adiabatic boundary surface determined as a section 0.2 m inside the pane and a corresponding section in the roof construction at least 0.5 m from the connection. The calculations are carried out otherwise like pointed out in annex B. The heat flow through possible rafters around the window has to be included in the roof's transmission coefficient.

Figure C.5 – Calculation model at determination of overall two-dimensional heat flow through connec-

tion, roof construction and window

Figure C.6 – Calculation model at determination of the heat flow through the rafters in roof construction

with rafters.

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Figure C.7 - Calculation model at the determination of heat flow through the window. It's assumed that

there is the same overlap between the insulation and the roof window's frame (X) as used at the determina-tion of the window's U value, cf. DS/EN ISO 12567-2

Figure C.8 – Example of connection around roof window

Example With a two-dimensional calculation program is the overall two-dimensional heat flow through the construction shown in figure C.8 determined to 15.823 W/m. At the calculation is used a difference between in- and outdoor temperature at 20 °C. The one dimensional heat flow through 300 mm of the roof construction in a typical section between the rafters de-termined for 1.076 W/m equivalent to

1.076 W/m/0.300 m = 3,587 W/m² The heat flow through a rafter and 500 mm of the roof construction on each side of the rafter are determined to 3.949 W/m. The heat flow through the rafter is determined to

3.949 W/m - 2· 3.587 W/m²· 0.500 m = 0.362 W/m The heat flow through the roof window is determined to 11.955 W/m. The linear loss for the connection around the roof window is determined after this to sa = (15.823 W/m - 3.587 W/m²· 0.530 m - 0.362 W/m - 11.955 W/m)/20 °C = 0.080 W/mK If the roof window is lowered e.g. 30 mm more proportional to the roof construction, so that the insulation goes 50 mm up on the side of the window's framework, the heat loss is reduced through the window by 0.057 W/mK. The connection's linear loss is only changed a little (to 0.079 W/mK), because the connection's height and insu-lation are unchanged.

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Annex D (normative)

Determination of linear loss for outer wall foundations

D.1 Linear loss for outer wall foundations at terrain deck By the determination of the line loss f for outer wall foundations at terrain decks there are considered both the heat flow in the foundation, the two-dimensional heat flows itself in the outer wall and the terrain deck up to the foundation as well as the dynamic two-dimensional heat flows in the soil around the foundation. The line loss f in W/mK for an outer wall foundation is determined by 1. calculate the overall two-dimensional heat flow through the foundation as well as the lowest 1.5 m of the outer

wall and the outer 4.0 m of the terrain deck, see figure D.1 2. deduct the corresponding one dimensional heat flows through the outer wall and the terrain deck 3. divide by the average difference between in- and outdoor temperature. The heat flows are determined from calculations on an annual basis like average values for the period from Sep-tember until and including May and are pointed out per meter of foundation. At the calculation are ignored heat flows in the foundation’s longitudinal direction as well as heat exchange through the adiabatic boundary surface determined of a vertical section in 20.0 m horizontal distance from the foundation’s outside, a corresponding vertical section in 4.0 m horizontal distance from the foundation’s inside as well as a hori-zontal plan situated 20.0 m below terrain, see a figure D.1.

Figure D.1 – Calculation model at determination of the linear loss for outer wall foundations at terrain deck

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DS 418:2011

Figure D.2 – The outdoor temperature’s progress during the year at determination of the linear loss for

outer wall foundations at terrain deck

At the calculations is used a constant indoor temperature on 20 oC and an outdoor temperature determined as

where

u is the outdoor temperature in oC, see figure D.2 M is the time of the year in months (e.g. corresponds M = 5 to the middle of January).

All months are assumed to have the same length. In the period from September until and including May (M = 8.0 to M = 12.0 as well as M = 0.0 to M = 5,0) the average outdoor-temperature according to the above men-tioned formula is 5.54 °C, and the average difference between in- and outdoor-temperature is 14.46 °C. For the soil volume the material parameters are used: Thermal conductivity: = 2.0 W/mK

Density· heat capacity: ·c = 2.0· 106 J/m³K At the calculations are used surface heat flow resistances like pointed out in table 6.2.1 D.1.1 Over all two-dimensional heat flow The overall two-dimensional heat flow through the foundation as well as the lowest 1.5 m of the outer wall and the outer 4.0 m of the terrain deck are determined by carrying out a calculation for the cross section shown in figure D.1. At the calculation the average overall heat flow is determined through the inside surfaces in W/m in the period September till May as well as the average temperature in the same period in a reference point right below the capil-lary breaking layer in the terrain deck and in 4.0 m distance from the foundation. The calculation can be carried out with a simulation program that uses numerical methods for determining the tran-sient (time-depending) temperature conditions and heat flows in the construction and the soil. At the calculation the cross section is split up in figure D.1 in smaller elements with identical material data. For each time step the tem-perature is calculated in all the elements and the heat flows between the elements. The elements have to be so small that further splitting up will not change the calculation result considerably, cf. DS/EN ISO 10211. That can normally be managed by applying elements to at most 25 x 25 mm to describe the foundation and those parts of the outer wall, the terrain deck and the soil that is closest to the foundation. In bigger distance from the foundation there can be used bigger elements. Thin insulation layers can possibly be enclosed as heat resistances in the model. At the calculation should be used time steps, which give a stable calculation for all elements.

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DS 418:2011

The calculation is continued, until the heat flow through the inside surfaces in December the last year differs less than 1 pct. from the heat flow in December the previous year. That can normally be managed by doing a course through 10 years. If the temperature in the reference point below the terrain deck cannot be read directly, the temperature should be determined by linear interpolation between the temperatures in the two nearest calculation points immediately be-low and above the reference point. By the interpolation the geometry is taken into consideration, but not necessarily disparity in material data. D.1.2 One-dimensional heat flow through outer wall and terrain deck The one dimensional heat flows through the lowest 1.5 m of the outer wall and through the outer 4.0 m of the ter-rain deck are also determined for the period from September until and including May. At the calculation quasi-stationary conditions are assumed. At calculation of the heat flow through the terrain deck the earlier determined reference temperature is used as a temperature right below the capillary breaking layer for the whole terrain deck, and the soil’s heat resistance is ig-nored.

Table D.1 – Example of calculated overall heat flow through the internal surfaces and temperature in the reference point in the middle of the month in the last year in the calculation period

Month Heat flow In W/m

Temperature in the reference Point in oC

January 19,44 13,22

February 20,18 12,81

March 19,52 12,46

April 17,66 12,28

May 15,08 12,31

June 12,49 12,54

July 10,56 12,91

August 9,83 13,33

September 10,48 13,68

October 12,35 13,86

November 14,92 13,83

December 17,52 13,60

Example With a two-dimensional dynamic calculation program there has been determined for a construction the overall heat flows through the inside surfaces and temperatures in the reference point in the middle of the month in the last year of the calculation period (see table D.1). In the middle of December the year before there has also been determined an overall heat flow through the inside surfaces on 17.56 W/m. The transmission coefficient for the outer wall has been estimated at 0.237 W/m²K. The transmission coefficient for the terrain deck determined between the room and the reference point right below the capillary breaking layer has been estimated at 0.276 W/m²K. The overall average heat flow through the inside surfaces in the period September to May is estimated at 16.35 W/m. The average temperature in the reference point in the same period is estimated at 13.12 °C. The overall heat flow through the inside surfaces in December the last year in the calculation period differs about 0.23 % from the heat flow in December the last year.

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The one dimensional heat flow in the period September to May through the lowest 1.5 m of the outer wall is deter-mined to

1.5 m· 0.237 W/m²K· 14.46 °C = 5.14 W/m and through the outer 4.0 m of the terrain deck it's determined to

4.0 m· 0.276 W/m²K· (20.00 °C - 13.12 °C) = 7.60 W/m. The linear loss for outer wall foundation is determined after this to

f = (16.35 W/m - 5.14 W/m - 7.60 W/m)/14.46 °C = 0.25 W/mK.

D.2 Linear loss at foundations below doors and windows at terrain deck

By the provision of the linear loss f for foundations below doors and windows at terrain deck there are considered both the heat flow in the foundation, the two-dimensional heat flows in the terrain deck up to the foundation as well as the dynamic two-dimensional heat flows in the soil around the foundation. The calculation of the linear loss is made in this context analogously with the calculation of the linear loss for outer wall foundations with one difference that door/window isn't included in the calculation model. Instead there are en-closed an adiabatic boundary surface, where the door/the window would be adjacent to the foundation. The following example illustrates the method. Example In figure D.3 is shown a vertical section in the connection between a door and foundation.

Figrue D.3 – Vertical cross-section in connection between door and foundation The construction is shortly described in the following. The terrain deck consists (from top) of: 100 mm concrete (λ= 1,9 W/mK) 2 x 100 mm insulation (λ= 0,038 W/mK) 300 mm light clinker (λ= 0,085 W/mK), where the lower 75 mm is reckoned capillary breaking (λ= 0,102 W/mK)

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The U-value for the terrain deck is determined as shown in table D.2

Table D.2 – Calculation of U-value for terrain deck

Terrain deck D m

λ W/mK

R m2k/W

Soil heat flow resistance Light clinker, capillary breaking

Light clinker, dry construction Insulation

Concrete

Inside heat flow resistance

- 0,075

0,225 0,200

0,100

-

- 0,102

0,085 0,038

1,900

-

1,500 0,735

2,647 5,263

0,053

0,170

ΣR =

U =

10,368 m2k/W

0,096 W/ m2k

U-value without soil heat flow resistance U = 0,113 W/ m2k

Note that it in connection with the deduction calculation of the heat loss through the terrain deck isn't included soil heat flow resistance in the calculation of the terrain deck’s U value. This is due to the fact that the deduction calcu-lation is included in the temperature in the reference point, which is situated immediately below the terrain deck construction.. The foundation consists of 3 courses of light clinker blocks. In the upper course are used 1 piece 100x200 mm of light clinker block (λ =(0.25 W/mK) as well as 40x200 mm of insulation (λ =(0.038 W/mK). In middle and lowest course are used 410x200 mm of light clinker blocks (λ =0.25 W/mK) with 110 mm of central insulation (λ = 0.038 W/mK). The calculation of the linear loss coefficient is made analogously with calculation of linear loss coefficients for foun-dations below outer walls (see possibly annex D.1), as however there is imported an adiabatic border in the con-nection between the door and the foundation (the adiabatic border consequently is 100 mm long, see figure D.4). The calculation model contains exclusively terrain deck and foundation, and therefore no deduction calculation for the door party has to be made. In a figure D.4 is shown the placement of the adiabatic border between foundation and door (marked by the two vertical lines).

Figure D.4 – Placement of adiabatic border between foundation and door

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DS 418:2011

Like for foundations below outer walls the result of the calculation is the overall two-dimensional heat flow through the detail as well as the temperature in the reference point (that is immediately below the terrain deck construction, in the middle below the building). The deduction calculation covers exclusively the one dimensional heat loss through the terrain deck. The deduction is determined as the U-value for the terrain deck (see table D.2) multiplied by the average temperature in the refer-ence point (see table D.1) multiplied by the terrain deck’s extent in the model. The terrain deck’s extent is in this context reckoned as the distance from the internal side of the outer wall, which in this case also corresponds to the internal side of the foundation, to the middle of the building. In table D.3 have all results been arranged.

Table D.3 – Calculation results

Month Temperature in Reference point

oC

Total 2D

W/mK

Terrain deck 1D

W/mK

Linear loss

W/mK

January February

March

April

May June

July August

September October

November

December

11,18 10,74 10,29

9,94

9,79 9,88

10,19 10,63

11,08 11,43 11,57

11,48

7,14 7,49 7,48

7,11

6,49 5,78

5,17 4,82

4,83 5,20 5,82

6,53

4,13 4,13 4,13

4,13

4,13 4,13

4,13 4,13

4,13 4,13 4,13

4,13

3,01 3,35 3,34

2,98

2,36 1,65

1,04 0,69

0,70 1,06 1,68

2,39

Medium heating 10,83 6,45 4,13 2,32

The calculation of the one-dimensional deduction through the terrain deck is done as follows:

The linear loss coefficient can now be determined as the average for the heating period divided by the average dif-ference between in- and outdoor temperature, this means:

D.3 Linear loss for the basement outer wall foundations Linear loss f for basement outer wall foundations, see figure 6.13.9 and 6.13.10, are determined in principle as for outer wall foundations at terrain deck. At calculation of the linear loss the basement outer wall is included up to ter-rain, but so that there is an overall height of basement outer wall and ordinary outer wall of at least 1.5 m. The one dimensional heat flow through the basement floor is determined in the same way as the one dimensional heat flow through a terrain deck. For basement outer wall foundations that lie deeper than 0.5 m, it can by the determination of the foundation be as-sumed that the outer wall construction continues up above terrain unchanged to an overall height of 1.5 m. For basement outer wall foundations that lie closer to terrain than 0.5 m, it has by the determination of the foundation to be considered the meaning of the construction above terrain, e.g. the ordinary outer wall construction and the con-nection between basement outer wall and ordinary outer wall.

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In order to determine the heat loss through the basement outer wall an extra two-dimensional calculation is made, where in the calculation model a horizontal adiabatic boundary surface from the inside to the outside of the base-ment outer wall is enclosed in a level with finished floor. The adiabatic boundary surface can possibly be enclosed as a great resistance that prevents the heat flow through the boundary surface. The in this way determined heat flows through the basement outer wall is deducted together with the one dimensional heat flow through the base-ment floor. A possibly necessary part of the outer wall up to an overall height of 1.5 m should also be included in the above described two-dimensional deduction of the basement outer wall.

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Annex E (normative)

Control demands for not CE-marked heat insulation products The relevant systems for the attestation of agreement for heat insulation-products are system 3 and system 1+3 with reference to commission decision 1999/99/EF with later change dated 2001.01.08. For heat insulation-products, which are to be classified for building products' reaction on a fire in the classes A1, A2, B and C, and where the products' classification are improved concerning reaction on a fire through addition of fire obstructing or reduction of organic material, system 1-3, is used, see table E.1 For all other heat insulation-products system 3 is used, see table E.1 For the attestation of agreement for heat insulation-products the following general demands are valid:

A running production control and a quality management system have to be established. The characteristics which are to be first-timed tested, appears from harmonized product standards' annex

ZA for similar products. There are no demands for audit tests on products.

Table E.1 – Control demands for not CE-marked products

Task Attestation of agreement

system

Attestation of agreement

system

System 3 System 1+3

Establishment of internal quality control

The manufacturer's responsibility Is inspected by notified1) certification organ

Select samples of tests for first-time testing at a notified laboratory

Selected by the manufacturer Selected by the notified1) laboratory

First-time testing Performed by the notified1) laborato-ry and the manufacturer

Performed by the notified1) laborato-ry and the manufacturer

Running inspection of the internal quality control (system and testing results)

The manufacturer’s responsibility Is inspected by the notified1) certifi-cation organ twice a year

Declaration of agreement. This declaration should be confirmed once per year.

Performed by the manufacturer on the basis of first-time testing by the notified1) laboratory and own first-time testing.

The notified1) certification organ issue a certificate, the manufacturer subsequently issue an agreement statement after control that inspec-tion- and testing reports fulfill the demands in the relevant product standard.

1) Notifications normally refer to an EN-product standard. For not CE-marked products as mentioned in chapter 7 and this annex E an accreditation is accepted by DANAK or corresponding accreditation organ.

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Rules for declaration of the insulation ability The declared thermal conductivity, λdekl is determined by the producer, so that 90 % of the yearly production with 90 %' s safety is better than the declared value (90 % confidence level). The declared thermal conductivity should therefore fulfill: λdekl >= λ90/90 where λ90/90 = λaverage + k· s where k is found in the table below, and s is the standard deviation of the measuring results. The demand for minimum number of direct measuring of the thermal conductivity with reference to corresponding European product standards are two per year. Table E.2 – Values of k for one-sided 90 % tolerance interval with a 90 % confidence level (see above) Number of test results

2 3 4 5 6 7 8 9 10 11 12 13 14 15

k 10,25 4,26 3,19 2,74 2,49 2,33 2,22 2,13 2,07 2,01 1,97 1,93 1,90 1,87

See DS/ISO 16269-6, table D.3 for other number of test results

Test results, which can be used for calculation of the declared heat insulation ability, are direct measuring within the time last 12 months running. In cases that the number of test results is less than 10, it's allowed to increase the period, until number of test results is 10, but with a maximum time period in 36 months.

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Annex F (normative)

Design values for brick, concrete and other building materials

This normative annex contains a number of diagrams with design values for the thermal conductivity for brick, lightweight concrete, light clinker concrete and mortar/concrete as well as tables with design values for a number of building materials etc. Design values for brick, sand-lime brick, lightweight concrete, light clinker concrete and mortar/concrete is shown on figure F.1 to F.4. The values have been determined on the basis of the standards DS/EN 1745 and DS/EN 1520. 50-% quantile have been used and been corrected for moisture content. The curves have been corrected within the calculation accuracy to obtain more even curves. The same moisture content has been assumed for all densities. For brickwork is used mortar with density 1 800 kg/m³.

Table F.1 – Provided moisture content and moisture correction coefficients ƒu and ƒy

Moisture content Moisture correction coefficients

Outside Inside ƒy ƒu

Weight percent m3/m3 kg/kg

Mortar 3 1,5 4

Brick 1,5 0,5 10

Sand-lime brick 3 2 10

lightweight concrete 6 3,5 4

Light clinker concrete, basement 6,5 6,5 4

Light clinker concrete, blocks 3 1,5 4

Concrete 2,5 1,5 4

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Figure F.1 – Brick and lime-sandstone – λ-design in W/mK as function of the density in kg/m3

Curve A: Internal walls of brickwork Curve B: External walls of brickwork Curve C: Internal walls of sand-lime brick Curve D: External walls of sand-lime brick

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Figure F.2 –Lightweight concrete – λ-design in W/mK as function of the density in kg/m3

Curve A: Internal blocks and plates with glued joints or mounted in forms, plates in storey height Curve B: External blocks and plates with glued joints or mounted in forms, plates in storey height Curve C: Internal blockwork approximately 0.6m long and 0.2m high Curve D: External blockwork approximately 0.6m long and 0.2m high

Conditions: Block-work is carried out with 10mm joints

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DS 418:2011

Figure F.3 – Light clinker concrete – λ-design in W/mK as function of the density in kg/m3

Curve A: Internal - blocks and plates with glued joints or mounted in forms Curve B: External - plates in storey height and other larger elements Curve C: Internal blockwork approximately 0.5m long and 0.2m high Curve D: External blockwork approximately 0.5m long and 0.2m high Curve E: Basement walls below terrain, made by blocks of light clinker concrete Curve F: Blockwork of light clinker concrete in brick format Conditions: Block-work is carried out with 10mm joints At reinforced lightweight concrete the gross-density is used including reinforcement. For light clinker concrete in foundations without possibility of ventilation is included a thermal conductivity for ex-ternal material increased with 50 %. For the upper 0.4 m of a foundation for a terrain deck construction, reckoned from top of ground, can be used values according to curve D: External blockwork approximately 0.5m long and 0.2m high, assuming that the foundation is sealed against moisture penetration.

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DS 418:2011

Figure F.4 – Mortar/concrete – λ-design in W/mK as function of the density in kg/m3

Curve A: Internal concrete Curve B: External concrete Curve C: Internal mortar Curve D: External mortar

Conditions: By reinforced concrete with 1 volume-% steel, a λ-value internal and external of 2.44 and 2.54 W/mK respectively, can be applied. By reinforced concrete with 2 volume-% steel, a λ-value internal and external of 2.64 and 2.76 W/mK respectively, can be applied.

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DS 418:2011

Design values for other building materials Table F.2 contains a number of values.

Table F.2 Design values for other building materials

Material or use Density

kg/m3

Design thermal conductivity W/mK

Stone, tiles, glass, ceramic

Granite

Gneiss

Basalt

Limestone

Marble

Slate

Sandstone

Tiles, clay

Tiles, concrete

Ceramic tiles, porcelain

Constructional glass

2500 –2700

2400 – 2700

2700 – 3000

2600

2800

2000 – 2800

2600

2000

2100

2300

2600

2,8

3,5

3,5

2,3

3,5

2,2

2,3

1.0

1.5

1.3

0.8

Plastic and rubber

Polycarbonate

PVC

Polyamide (Nylon)

Epoxy

Synthetic rubber

Linoleum

1200

1390

1150

1200

1200

1200

0.20

0.17

0.25

0.20

0.24

0,2

Wood and wood-bases boards

Wood1)

Construction wood (softwood) 1)

Hard wood1)

Plywood

Chipboards

450 – 700

450

700

300 – 1000

300 - 900

0,12 – 0,18

0,12

0,18

0,09 – 0,24

0,10 – 0,18

Soil, drainage material

Moist soil (moraine)

Coarse cinders in soil

Clay

Sand and gravel

Pebble layer as capillary breaking layer

1900

800

1200 – 1800

1700 - 2200

2,3

0,4

1,5

2,0

0,7

Metal

Aluminium

Zinc

Bras

Bronze

Cupper

Silver

Led

Soft steel

2700

7100

8400

8700

8900

10500

11300

7800

220

110

100

65

380

420

35

55

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DS 418:2011

Stainless steel

Cast iron

7900

7200

17

50

(is continued)

Material or use Density

kg/m3

Design thermal conductivity W/mK

Water, air

Water (stagnant)

Ice at 0°C

Snow at 0°C

Snow at 0°C

Air (stagnant)

1000

900

300

100

1,3

0,6

2,2

0,23

0,05

0,024

Other

Plasterboard with paper

900

0,25

1) For all wood is provided that density correspond to balance with 65% RF at 20 oC

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DS 418:2011

Annex G (informative)

Design values for calculation of existing constructions in connection with rebuilding and renovation

Material and application Density

kg/m3

Design thermal conductivity W/mK

Cellular plastic injected on site Polyurethane Ureaformaldehyde

8 - 30 0,055 0,070

Cellular plastic filler Polystyrene pellet/granulate

10 - 20 0,050

Other materials Cellulose fibers, loose, slab, rolls Expanded perlite Cotton wool Sheep wool Wood wool, chip, shaving Grain, granulated, expanded Glass bead, loose, whole Polyester fibres Straw, rolls, mats, granulate

30 -150 25 – 40 25 – 75 30 – 90 170 – 190 150 – 190 25 – 30 30 - 100

0,06 0,05 0,055 0,060 0,10 0,10 0,10 0,060 0,095

Mineral wool Above terrain Towards soil Loose and granulated

15 - 300 0,050 0,055 0,050

Expanded polystyrene Above terrain Towards soil

10 - 45 0,050 0,055

The values in the list apply, when no value for the concerned product, valid at the time of application, can be determined.

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Annex H (informative)

Detailed calculation procedure for the overall U-value for skylights The overall U value for skylight domes (in the following called skylight) is detailed calculated after the method in DS/A ISO 10077-1 and DS/EN ISO 10077-2. There are three contributions (see figure H.1): Ug originating in the dome Uk originating in the frame linear loss through the framework between dome and frame. For surfaces on casement and frame as well as for surfaces in cracks with opening bigger than 2 mm against out- or indoor air the heat flow resistance in table 6.2.1. is used.

Figure H.1 – The 3 contributions for the overall U-value

Where A’ = Ag + Ak + Ar

Ug is the transmission coefficient in the middle of the dome in W/m2K Uk is the transmission coefficient for the frame in W/m2K is the linear loss for the casement in W/mK lis the perimeter of the skylight in m Ag is the dome's area in m2 Ak is the frame area in m2 Ar is the casement area in m2 A’ is the overall heat transmitting area in m2

The transmission coefficient for the dome (Ug) can be calculated according to DS/EN 673. Calculation of the frame’s transmission coefficient (Uk) is done by building a simple model of the frame for a homogeneous segment.

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The linear loss () is determined by calculating at first the transmittans Ltot for the whole skylight in a two-dimensional calculation program. After this the linear loss can be found such as: = Ltot - Uk· lk - Ug· lg where Ltot is the transmittans for the segment (see figure H.2) in W/mK lk is the frame height used in the segment in m lg is dome segment used in the segment in m. An approached external surface is determined for the skylight, called the overall heat-transmitting area (A'), that the heat loss is related to by the provision of the U-value for the whole skylight. The overall area A' is calculated as the sum of Ag, Ak and Ar, (external area of dome frame and casement) equivalent to that the frame profile's surface area constitutes a part of the real transmission area. In order to define the respective parts of area it's necessary to make a number of calculation-technical divisions and definitions of the skylight profiles. The divi-sions are shown in figure H.2.

Figure H.2 - calculation-technical divisions of skylight profile

The area of the dome Ag is calculated as the dome's external surface area, from the place where the dome meets the frame profile. The area of the frame Ak is defined as the external area that normally is determined as the perimeter (at the medium frame height) of the external frame measure multiplied with the frame height lk. The frame height lk is defined as the distance measured along a straight line in parallel with the frame from a horizontal plan below the frame to a horizontal plan above the window frame. The horizontal plan below the frame is defined as the upper situated by the following two levels:

1. The frame segment’s underside 2. The top side of the insulation in the roof.

The area of the frame Ar is found as the perimeter of the external frame measure at the frame multiplied by the height of the frame lr added the horizontal (projected) area between the dome's end and the vertical plan de-termined of the frame's external demarcation at the frame. The horizontal area can normally be determined as the distance Xs (see figure H.2) multiplied with the perime-ter of the external frame measure at the frame. The line loss is calculated along the perimeter of the skylight l. The perimeter is calculated as external frame measure.

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DS 418:2011

Annex I (informative)

Calculation example – Existing building with window with two layer energy pane The U-value for an outward wooden window should be calculated. The window has one two layer energy pane, 4-15-4, 90 % argon-filled and with one low emission covering. Case A: A distance profile of galvanized steel is used. Case B: A distance profile of plastic (warm edge) with a L-value at 0.24 W/mK. Width of a frame/casement (sides, top and bottom) is 100 mm. The frame thickness is 116 mm. The frame thickness is 56 mm. The light measure will thus become 988· 988 mm. The formulas in section 6.8 are used. A' (overall heat-transmitting area in m2) = 1.188· 1.188 = 1.41 m2 lg = 4· 0.988 = 3.95 m Ag = 0.988· 0.988 = 0.98 m2 Ap = 0.00 m2 Af = 1.41-0.98 = 0.43 m2 Ug (compare figure N.2, 15 mm glass distance) = 1.65 W/m²K Uf (compare figure 6.8.1, average thickness of frame and casement 86 mm) = 1.60 W/m²K Case A: Distance profile of galvanized steel: g (compare table 6.8.2) = 0,09 W/mK

Case B: Distance profile of plastic: g (compare table 6.8.3) = 0,07 W/mK

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Annex J (informative)

Concrete sandwich elements – Calculation example In figure J.1 has been drawn up an example of a little industrial element. The element is in all 340 mm thick (that is 175 mm insulation, 75 mm front casting and 90 mm rear casting), and the rib insulation is 70 mm. λ class for the insulation material is 38, but an equivalent λ-value is used for the insulation at 0.040 W/mK, as in this way is taken into account for straps and dowels (75 mm² stainless steel per m2). The U-value calculation The real (three-dimensional) heat flows in the concrete sandwich element are assumed to be able to be approx-imated with heat flows in two dimensions, so that the U-value for the element can be compounded of one di-mensionally calculated U-values and of some linear loss additions. The U value for the element is compounded of the one dimensional U-values for the completely insulated parts as well as for the parts with reduced insulation and of some linear loss additionsk.

where

lk is the length of the thermal bridge with the linear loss addition k n is the number of layers k is the number of cold bridges At the calculation of the U-values penetrating reinforcement (straps and dowels) should be taken into consider-ation at area weighting of the λ-values for reinforcement and insulation, as a λ' - calculation according to section 6.6. values depend on the linear thermal bridge's geometry (thickness of front- and rear casting, full insulation thickness, rib width and thickness) and the thermal conductivity for the applied materials (concrete and insula-tion). Calculation of the length of the linear thermal bridges The length of a linear thermal bridge is calculated as the length of the distance where a jump happens in insula-tion thickness, cf. figure J.1. In this example where the jump in insulation thickness is different for ribs and door rabbet, the rib length l2 and the door rabbet length l3 is calculated:

Calculation of U-value from one-dimensional heat flows At first the U-values for the two frequent cross sections. Next the areas of the two cross sections are calculated: A1 = 3,27 m2 A2 = 4,13 m2

Is the element’s total transmission area

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DS 418:2011

From this the element’s area weighted one-dimensional U-value is calculated:

x1 = 300 mm x2 = 300 mm x3 = 100 mm x4 = 1000 mm y1 = 500 mm y2 = 1050 mm y3 = 100 mm y4 = 2200 mm y5 = 150 mm

Figure J.1 – Industrial element U-value from two-dimensional calculated linear loss The linear loss for the insulation thickness ‘jump’ is calculated by help of a two-dimensional calculation program or can be read in figure 6.10. The value of this size is: 2 = 0,011 W/mK The linear loss occurs in total: l2 = 0,3 + 3,35 + 1,8 + 3,35 + 0,3 + 2,3 + 1,2 + 2,3 = 1,49 m

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DS 418:2011

With this we get the total linear loss L for the element:

which is spread out on the element area:

The resulting U-value for the element is therefore:

U-value from three-dimensional calculation For comparing is below shown the U-value found from a three-dimensional heat flow calculation for the element:

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Annex K (informative)

Standards and proposals for standards, referring to DS 418 In section 0.3 are stated the standards, which refer to DS 418. Below is shown number as well as title.

DS 469 Varmeanlæg med vand som varmebærende medium

DS/EN ISO 14683 Kuldebroer i bygningskonstruktioner – Lineær varmetransmittans – Forenklede metoder og tabelværdier

DS/EN 823 Termisk isolering i byggeriet – Produkter – Bestemmelse af tykkelse

DS/EN 1520 Præfabrikerede armerede elementer af letklinkerbeton med åben struktur

DS/EN 14351-1 + A1 Vinduer og døre – Produktstandard, ydeevneegenskaber – Del 1: Vinduer og yderdøre uden brandmodstandsevne og/eller røgtæthedsegenskaber

DS/EN ISO 6946 Bygningskomponenter og bygningsdele – Værdier for termisk isolans og transmissions koef ficient – Beregningsmetode

DS/EN ISO 13789 Bygningers termiske ydeevne – Varmeoverføringskoefficienter for transmission og venti lation – Beregningsmetode

DS/EN ISO 10456 Byggematerialer og -produkter – Hygrotermiske egenskaber –Tabeldesignværdier og proce- durer til bestemmelse af termiske deklarerede værdier og termiske designværdier

DS/EN 1745 Murværk og murværksprodukter – Metoder til bestemmelse af termiske designværdier

DS/EN 1873 Præfabrikeret tilbehør til tagdækning – Individuelle ovenlys af plastmaterialer – Pro duktspecifikation og prøvningsmetoder

DS/EN ISO 10211 Kuldebroer i bygningskonstruktioner – Varmestrømme og overfladetemperaturer – De taljerede beregninger

DS/EN 673 Bygningsglas – Bestemmelse af transmissionskoefficient (U-værdi) – Beregningsmetode

DS/EN ISO 12567-1 Vinduer og døre – Termisk ydeevne – Bestemmelse af transmissionskoefficient ved hot box- metoden – Del 1: Komplette vinduer og døre

DS/EN ISO 12567-2 Termisk ydeevne for vinduer og døre – Bestemmelse af transmissionskoefficient ved hot box- metoden – Del 2:Tagvinduer og tilsvarende vinduer

DS/EN ISO 10077-1 Termisk ydeevne for vinduer, døre og skodder – Beregning af varmetransmission – Del 1: Generelt

DS/EN ISO 10077-2 Termisk ydeevne for vinduer, døre og skodder – Beregning af varmetransmission – Del 2: Numerisk metode for rammer

DS/EN ISO 9251 Termisk isolering – Varmetransmissionsforhold og materialeegenskaber –Terminologi

DS/EN ISO 7345 Termisk isolering – Fysiske størrelser og definitioner

DS/EN ISO 9288 Termisk isolering – Varmeoverføring ved stråling – Fysiske størrelser og definitioner

DS/EN ISO 8990 Termisk isolering – Bestemmelse af isolans ved brug af kalibreret og beskyttet varme kasse (hot box)

DS/EN 14963 Tagbelægninger – Kontinuerlige ovenlys af plast med eller uden opbygning – Klassifika tion, krav og prøvningsmetoder

DS/EN 12412-2 Termisk ydeevne for vinduer, døre og skodder – Bestemmelse af transmissionskoeffi- cient ved hot box-metoden – Del 2: Rammer

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DS 418:2011

Harmonized product standards, referring to DS 418 and relating to insulation products DS/EN 13162 Termisk isolering i byggeriet – Produkter – Fabriksfremstillede produkter af mineraluld

(MW) – Specifikation

DS/EN 13163 Termisk isolering i byggeriet – Produkter – Fabriksfremstillede produkter af ekspanderet poly- styrenskum (EPS) – Specifikation

DS/EN 13164 Termisk isolering i byggeriet – Produkter – Fabriksfremstillede produkter af ekstruderet poly- styrenskum (XPS) – Specifikation

DS/EN 13165 Termisk isolering i byggeriet – Produkter – Fabriksfremstillede produkter af stiv polyurethan- skum (PUR) – Specifikation

DS/EN 13166 Termisk isolering i byggeriet – Produkter – Fabriksfremstillede produkter af phenolskum (PF) – Specifikation

DS/EN 13167 Termisk isolering i byggeriet – Produkter – Fabriksfremstillede produkter af celleglas (CG) – Specifikation

DS/EN 13168 Termisk isolering i byggeriet – Produkter – Fabriksfremstillede produkter af træbeton (WW) – Specifikation

DS/EN 13169 Termisk isolering i byggeriet – Produkter – Fabriksfremstillede produkter af ekspanderet perlit (EPB) – Specifikation

DS/EN 13170 Termisk isolering i byggeriet – Produkter – Fabriksfremstillede produkter af ekspanderet kork (ICB) – Specifikation

DS/EN 13171 Termisk isolering i byggeriet – Produkter – Fabriksfremstillede produkter af træfibre (WF) – Specifikation

DS/EN 13172 Termisk isolering – Produkter – Vurdering af overensstemmelse

DS/EN 14063-1 Termisk isolering i byggeriet – Produkter – In situ-fremstillede ekspanderede letklinker (LWA) – Del 1: Specifikation for løsfyldprodukter før indbygning

prEN 14063-2 Termisk isolering i byggeriet – Løsfyldprodukter – Letklinker, der formes på installationsste- det – Del 2: Specifikation for det installerede produkt

DS/EN 14064-1 Termisk isolering i byggeriet – Løsfyldprodukter – Mineraluld, der formes på anvendelsesste- det – Del 1: Specifikation for løsfyldprodukter før installation

DS/EN 14064-2 Termisk isolering i byggeriet – Løsfyldprodukter – Mineraluld, der formes på anvendelsesste- det – Del 1: Specifikation for installerede produkter

Other standards with relevance for calculation of building’s heatloss DS/EN 13370 Bygningers termiske ydeevne – Varmetransmission via jord – Beregningsmetoder DS/EN 674 Bygningsglas – Bestemmelse af transmissionskoefficient (U-værdi) med beskyttet

varmepla- deapparat – Metode DS/EN 675 Bygningsglas – Bestemmelse af transmissionskoefficient (U-værdi) med

varmestrømsmåler – Metode DS/EN 410 Bygningsglas – Bestemmelse af lys- og solstrålingskarakteristika

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DS 418:2011

Annex L (informative)

Calculation example – DS 418

All measures are in mm

Figure L.1 – Plan of building that is used as example

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DS 418:2011

Level height in meter

Figure L.2 Cross section A-A of building, that is used as example As a calculation example it's used the in figure L.1 and L.2 showed single-storeyed house with gross floor area of 133 m2. Some measures appear solely from the calculations and are not necessarily indicated in the drawings. Constructions and insulation thicknesses have been chosen as being typical to obtain a construction that will fulfill the provisions in building regulations 2010. The example's aim is alone to guide regarding calculation of transmission coefficients and heat loss. At calculation of outer wall areas is used as vertical measure the distance from top side of finished floor to top side of ceiling insulation: 2.425 m + 0.416 m = 2.841 m. From the outer wall's overall area is deducted the sum of the areas for the building parts (windows, doors, beams etc.) which are included in the cavity wall. At calculation of ceiling area external measures are used, and at calculation of terrain deck area inside measures are used. In the house is: 4 facade windows, 2 roof windows, 1 bay window, 2 doors, some 1½- width door and 1 garden door. The facade windows, the bay window and the doors have 2 vertical rabbet elements, that each have a width of 0.1 meters and a height on 2,13 meters. Above the small window as well as above doors in scullery/hall/bedroom lies a 190 mm high, 210 mm wide and 1.4 m long beam of reinforced lightweight concrete. Above the intermediate-windows as well as above garden door is however placed of a 190x100 mm concrete beam with the length 2.5 m, and above the bay window the length is 6.5 m. The house's 2 roof windows have been mounted in the roof with light shafts that break through the insulation in the ceiling. The cross section area of a light shaft in the ceiling insulation's plan is 0.78 x 2.1 meters. The house has foundation along the whole perimeter with different solutions under outer wall and under bay window /outer doors. It's assumed that CE-marked insulation products are used.

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DS 418:2011

L.1 Transmission areas and length of linear loss Table L.1 – Measures of windows and doors and the circumference of the glass area

Numbers Hole measure Total area

Width (b) m

Height (h) m

Area (A) m2

Garden door 1 1,81 2,20 3,98

Roof windows 2 0,78 1,40 2,18

Small window in room 1 0,97 1,21 1,17

Intermediate-window 4 1,81 1,01 7,31

Doors in scullery/hall 2 0,97 2,20 4,27

Door in sleeping room 1 1,47 2,20 3,23

Bay window 1 6,101) 2,20 13,42 1) Indicates the width of window and not a real hole measure

Table L.2 – Overall length

The length of the vertical rabbets at connections between window/door and outer wall

l = 20 pieces 2,13 = 42,6 m

The length of insulation jump rabbet/outer wall between window/door and outer wall

l = 20 pieces 2,13 = 42,6 m

Table L.3 – Areas

Outer wall total (outside perimeter 49,44 m x outer wall’s height 2,841 m) 140,46 m2

Vertical window rabbets 4,26 m2

Reinforced light concrete beams above window- and door holes 1,06 m2

Concrete beams above window- and door holes 3,61 m2

Small window 1,17 m2

Medium window 7,31 m2

Doors in scullary/hall/bedroom 7,50 m2

Garden door 3,98 m2

Bay window 13,42 m2

Cavity wall excl. rabbet, reinforced light concrete beams and concrete beams 98,25 m2

Cavity wall incl. rabbet, reinforced light concrete beams and concrete beams 107,18 m2

Terrain deck 113,00 m2

Ceiling total 131,50 m2

Light shaft ( 2 pieces of 0,78 meter x 2,1 meter) 3,28 m2

Ceiling construction 128,22 m2

Light shafts (2 pieces of 6,81 m2) 13,62 m2

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DS 418:2011

L.2 Transmission coefficients For each of the following construction parts will be calculated a U-value with reference to chapter 6. Cross section drawings of the construction parts of outer wall, terrain deck as well as ceiling and roof is shown in figure L.3.

All measures in mm

Outer wall Terrain deck Ceiling and roof

Figure L.3 – Cross section drawing of outer wall, terrain deck and ceiling and roof

L2.1 Outer wall The majority of the outer wall consists of 518 mm cavity wall of bricks (1 800 kg/m³) and lightweight concrete (575 kg/m³, λ= 0.17 W/mKs). The front wall consists of 108 mm massive bricks, and the rear wall of 100 mm floor-high light weight concrete elements, connected with 6 wall ties of 3 mm stainless steel per m2. The cavity is insolated with 2x150 mm insulation, λ = 0.034 W/mK. At windows and doors' vertical sides rabbet elements are led all the way down to the foundation. In the rabbets is insolated with 70 mm thermal bridge insulation. Above the small window as well as over doors in scullary/hall/bedroom have been placed a 190x210 mm reinforced lightweight concrete beam. Above the remaining windows, above garden door and above the windows in the bay window has been placed a 190x100 mm concrete beam. A heat conducting connection between front wall and rear wall in the foundation’s top is reduced by the placement of 2 light clinker blocks containing 150 mm of insulation as well as including 1 solid light clinker block. The foundations are kept separate from the slab with 15 mm insulation (see figure 6.13.2, sketch a)). Transmission coefficient for outer wall is calculated with relation to section 6.7:

Insulation jump between rabbet and outer wall: Ψk= 0,00 W/mK (see table 6.7.1) The length of insulation jump rabbet/outer wall: l = 42,6 m In the following is ignored wall tie correction and linear loss for insulation jump rabbet/outer wall, when ∆Uf = 0 according to annex A table A.2 and Ψk < 0,02 W/mK. The reinforced light concrete beam’s λ is determined from density incl. reinforcement and is from the manufacturer told being 0,26 W/mK.

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DS 418:2011

Table L.4 – U-value for insulated wall

d m

λ W/mK

R m2K/W

U’ W/m2K

Outside surface resistance 0,04

Outer leaf of bricks 0,108 0,727 0,149

Insulation 0,300 0,034 8,824 Inner leaf of light weight concrete 0,100 0,588 0,588

Inside surface resistance 0,13

R = 9,730 0,103

Table L.5 – U-value for vertical rabbet with 70 mm thermal bridge insulation

d m

λ W/mK

R m2K/W

U’ W/m2K

Outside surface resistance 0,04 Outer leaf of bricks 0,108 0,727 0,149

Insulation 0,070 0,034 2,059

Inner leaf of light weight concrete 0,330 0,170 1,941

Inside surface resistance 0,13

R = 4,319 0,232

Table L.6 – U-value for reinforced light concrete beam

d m

λ W/mK

R m2K/W

U’ W/m2K

Outside surface resistance 0,04

Outer leaf of bricks 0,108 0,727 0,149

Insulation 0,190 0,034 5,588

Reinforced light concrete beam 0,210 0,260 0,808

Inside surface resistance 0,13

R = 6,714 0,149

Table L.7 – U-value for concrete beam

d m

λ W/mK

R m2K/W

U’ W/m2K

Outside surface resistance 0,04

Outer leaf of bricks 0,108 0,727 0,149

Insulation 0,300 0,034 8,824

Concrete beam 0,100 2,000 0,050

Inside surface resistance 0,13

R = 9,192 0,109

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DS 418:2011

Table L.8 – Contribution to U-value for concrete beam in table form Surface contribution Area

m2 U’-value W/m2K

U’ A W/K

Insulated wall 99,25 0,103 10,20

Rabbet 4,26 0,232 0,99

Reinforced beam 1,06 0,149 0,16

Concrete beam 3,61 0,109 0,39 Linear contribution Length

m Ψ-value W/mK

Ψl W/K

Insulation jump, rabbet 42,6 0,00 0,00

Total 108,18 11,74

U’ = 0,108 W/m2K According to annex A (normative) the U-value should be corrected for air gaps in the insulation and wall ties. The correction for air gaps by two layer insulation fixed to plane surface is level 0, which means: ∆U’’ = 0,0 W/m2K ∆Uf = 0 according to table A.2 ∆Ug = 0 W/m2K The outer wall’s U-value is 0,11 W/m2K

L.2.2 Connections around windows and doors There are rabbet elements with 70 mm of thermal bridge insulation at windows and doors' vertical sides. Above the more narrow windows and doors have been placed a 190x210 mm reinforced lightweight concrete beam. Above the door in kitchen/family room, the window in the kitchen as well as above the windows in the bay win-dow has been placed a 190x100 mm concrete beam. The window frame has been placed next to the thermal bridge interruption. The vertical rabbets by windows and doors: Ψ= 0.00 W/mK (table 6.12.1a) The length of the vertical rabbets by windows and doors: l = 42.6 m Reinforced lightweight concrete beams, for windows and doors: Ψ= 0.00 W/mK (table 6.12.1a) The length of the reinforced lightweight concrete beams to windows and doors: l = 5,6 m Concrete beam, for windows and doors: Ψ= 0.00 W/mK (table 6.12.1a) The length of concrete beam for windows and doors: l = 19.0 m

L.2.3 Windows and doors All facade doors and -windows have three layers of glass (4-12-4-12-4) with argon filling, low emission covering and warm edge. By windows with bars are used energy bars. U-values for CE-marked windows and doors have been given from producers.

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DS 418:2011

Table L.9 - U-values for building components Building component Placement in building U-value in W/m2K

Garden door Family room 1,19

Between façade window Kitchen/north west room/south west room and south east living room

1,05

Bay window Bay 1,10 Doors Scullery/hall/bedroom 1,16

Small façade window Bedroom 1,07

Roof windows Bathroom/toilet 1,70

L.2.4 Terrain deck

Transmission coefficient for terrain deck is calculated according to section 6.7 and 6.9:

From below the terrain deck consists of following: 200 mm light clinker, of which the lowest 75 mm are reckoned as capillary breaking light clinker layer 260 mm insulation 100 mm concrete with floor heating, damp proof membrane 14 mm parquet flooring. With relation to section 6.9 the heat resistance from the heat source's plan is calculated, and heat resistances over the heat source's plan as well as inside surface resistances are neglected. It's assumed that the heated floor lies in the middle of the concrete layer.

Table L.10 – U-value for terrain deck

d m

λ W/mK

R m2K/W

U W/m2K

Inside surface resistance 0,017

Parquet flooring 0,014 0,13 0,108

Concrete layer above floor heating 0,050 2,0 0,025

Concrete layer 0,050 2,0 0,025

Insulation 0,260 0,038 6,842

Light clinker, dry construction 0,125 0,085 1,470

Light clinker, capillary breaking layer 0,075 0,085 1,2 0,735

Resistance for soil 1,500

R = 10,573 0,0945

According to annex A (normative) the U-value should be corrected for air cracks in the insulation. Correction for air cracks by two layers of insulation is level 0, that is ∆U'' = 0 W/m²K. Compare section 6.1 U-values should be pointed out with two influential figures, and the U-value of 0.0945 W/m²K is therefore rounded off to 0.09 W/m²K. U value for terrain deck U = 0.09 W/m²K

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L2.5 Foundation Below glass bay and outer doors the upper part of the foundation consists (see also figure 6.13.7):

Outside 2 pieces of 190 mm high light clinker blocks with λ = 0,23 W/mK In the middle 100 mm insulation with λ = 0,040 W/mK Inside 100 mm insulation between slab and block in the 2nd course.

The bottom window frame of window /doors is made of wood, and the thickness of thermal bridge insulation be-low window /below doors next to the concrete plate is 100 mm. The linear loss for connection between foundation and bottom window frame below window /doors is ignored, as Ψk = 0,01< 0,02 cf. table 6.13.6b. The foundation’s Ψ- value below window-front/doors: 0.12 W/mK The length of foundation below window/doors is: 10,82 m Below the outer wall the foundation in the top consists of 2 pieces 190 mm high light clinker blocks with λ = 0,23 W/mK containing 150 mm of insulation with λ = 0,040 W/mK, including 1 piece 190 mm high, solid light clinker block. The foundation’s Ψ- value is: 0.11 W/mK The length of foundation is: 38.62 m

L2.6 Ceiling and roof The construction reckoned from below: 2x13 mm plaster on spaced battens, 45 mm insulation (λ = 0.034 W/mK) placed between tree battens, damp proof membrane, 125 mm of insulation (λ = 0.034 W/mK) containing foot of rafter, 195 mm uninterrupted insulation (λ = 0.034 W/mK) above rafter foot, ventilated roof space, tiles on bat-tens. In the inhomogeneous insulation layers is assumed putted up 45 mm of wood per 600 mm filled with insula-tion. Transmission coefficient with relation to section 6.6 R-value for spaced battens from section 6.6 R-value for roof space and roof from table 6.5 The middle thermal conductivity for inhomogeneous insulation layers:

Table L.11 – U-value for ceiling and roof

d m

λ W/mK

R m2K/W

U W/m2K

Surface resistance 0,140

Plaster board 0,026 0,25 0,104

Spaced battens 0,025 0,160

Insulation 0,045 0,042 1,073 Insulation 0,125 0,042 2,921

Insulation 0,125 0,034 5,735

Roof space and roof 0,300

R = 10,492 0,095

According to annex A the U-value should be corrected for air gaps in the insulation. The correction for air gaps at two layers insulation is level 0, which means ∆U'' = 0 W/m²K. U-value for ceiling: U = 0.10 W/m²K

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L2.7 Light shafts in connection with roof windows At the light shafts in connection with sky lights is built-up a construction, which from inside consists of: 2x13 mm plaster on spaced battens, 45 mm insulation (λ = 0,034 W/mK) put up between wooden battens, damp proof membrane, 195 mm of insulation (λ = 0,034 W/mK) put up between wooden battens, ventilated roof space, tiles on battens. In the inhomogeneous insulation layers is assumed an insulation put up 45 mm of wood per 600 mm filled with insulation. Transmission coefficient with relation to section 6.6 R-value for spaced battens from section 6.6 R-value for roof space and roof from table 6.5 The middle thermal conductivity for inhomogeneous insulation layers:

Table L.12 – U-value for light shafts

d m

λ W/mK

R m2K/W

U W/m2K

Surface resistance 0,140

Plaster board 0,026 0,25 0,104

Spaced battens 0,025 0,160

92,5% insulation, 7,5% wood 0,045 0,042 1,073

92,5% insulation, 7,5% wood 0,195 0,042 4,648

Roof space and roof 0,300

R = 6,427 0,156

According to annex A the U-value should be corrected for air gaps in the insulation. The correction for air gaps at two layers insulation is level 0, which means ∆U'' = 0 W/m²K. U-value for light shafts: U = 0.16 W/m²K

L.2.8 Connections around roof windows At connection between roof windows, the light shaft and roof there is a linear loss that by a producer has been estimated to 0.09 W/mK. Alternatively values from table 6.12.4 could be used. Connection between roof window, light shaft and roof: Ψ = 0.09 W/mK The length of connection between roof window, light shaft and roof: l = 8.7 m

L.2.9 Linear loss at connections Calculation of linear loss at connections with relation to section 6.14. As stated in section 6.14 corner connections causes (e.g. wall/ceiling and wall/wall) linear loss, when the two constructions create an angle with each other and thus a thermal bridge. In the following linear losses for the corner connections in the building are calculated, and as stated in section 6.14 both positive and negative linear losses from the corner connections are included. Corner connections with positive or negative linear loss are:

Corner between outer wall and outer wall Corner between outer wall and ceiling.

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L.2.9.1 Corner between outer wall and outer wall The building has three outer wall corners, as there isn't any outer wall corner at window bay. The height of each corner is 2.841 m (cf. figure L.2). Length of connection between outer wall and outer wall: l = 8.523 meters The outer wall corners are with heavy constructions, the insulation thickness is 300 mm. Cf. table M.1 the corner connection has a linear loss of - 0.07 W/mK.

L.2.9.2 Corner between outer wall and ceiling The building has a connection detail between outer wall and ceiling. The length of this can be found in figure L.1. Length of connection between outer wall and ceiling: l = 49.44 meters The ceiling is with horizontal insulation and with the slanting cutting-off of the insulation. With outer- and inner leaf of bricks, an insulation thickness in the outer wall of 300 mm as well as an insulation thickness in the ceiling of 365 mm we have by help of table M.5 a linear loss for corner between outer wall and ceiling of - 0.06 W/mK.

Table L.13 – Overall deduction for corner connections Ψ

W/mK l

m ∆t K

Φ W

Corner between outer wall and outer wall Corner between outer wall and ceiling

-0,07 -0.06

8,523 49,44

32 32

-19,1 -94,9

Deduction for corner connection -114,0 W

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L.3 Heat loss Calculation of transmission loss according to section 5 Overall is calculated with room temperature 20 oC, and the transmission areas from table L.2 are used.

Table L.14 – Overall transmission loss U

W/m2K A m2

∆t K

Φ W

Outer wall Garden door Roof windows Small window in room Between window Doors in scullery/hall Door in bedroom Window bay Terrain deck Ceiling and roof Light shafts

0,11 1,19 1,70 1,07 1,05 1,16 1,16 1,10 0,09 0,10 0,16

107,18 3,98 2,18 1,17 7,31 4,27 3,23

13,42 113,00 128,22 13,62

32 32 32 32 32 32 32 32 20 32 32

377,3 151,6 118,6 40,1

245,6 158,5 119,9 472,4 203,4 410,3 69,7

Ψ W/mK

l m

∆t K

Φ W

Vertical rabbet at window/door Foundation at outer wall Foundation at doors/window bay Connection at roof window/roof

0,00 0,11 0,12 0,09

42,6 38,62 10,82 8,7

32 42 42 32

0,00 178,4 54,5 25,1

Transmission loss total 2625 W

Is the deduction for corner connections included (Cf. L.2.9, table L.13) we get a transmission loss of 2625 + (-19) = 2606 W.

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Annex M (normative)

Thermal bridges at corners

M.1 Vertical outer wall connections

M.1.1 Generally The linear loss for outer wall corners with throug going uninterrupted insulation can for right-angleded corners be determined by the tables M.1-M.3 in section M.1.2. For not right-angleded corners section M.1.3. is used. The same size insulation thicknesses have been assumed in the two wall parts (that is symmetry). If there in a concrete case isn't any symmetry, the value is used for the insulating thicknesses that have the greatest linear loss. I.e. is used the largest insulation thickness too outward corners and the at smallest at ingoing (about outward and ingoing corners, see section 3.6). Concerning geometry and thermal conductivity for the constructions in annex M the values in sections M.6. are used.

M.1.2 Right-angeled corners The linear loss for heavy outer wall constructions can be determined from below mentioned table M.1 for respectively outward- and ingoing corners.

Figure M.1 – Example of outer wall corner with heavy constructions

Table M.1 – The linear loss Ψ in W/mK at outward- and ingoing corners, heavy constructions (concrete, bricks or light weight concrete=. The thickness of the outer leaf between 80 and 125 mm. (Interpolation is

accepted)

Thickness of insulation mm

At outward corner W/mK

At ingoing corner W/mK

125 -0,10 0,07

190 -0,08 0,06

290 -0,07 0,05 500 -0,06 0,04

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The linear loss for an outer wall corner connection in a light construction (figure M.2) with vertical posts in the corners are shown in table M.2 and M.3. In the tables is furthermore shown the linear loss for an outer wall corner connection for walls with unbroken inner leaf of concrete furred with 220 mm uninterrupted insulation and finished with plaster (figure M.3).

Figure M.2 – Outer wall corner made as a light construction with vertical posts in corner connection (The thickness of the external, ventilated covering is reckoned from outer side of wind gypsum to outerside of

covering)

Figure M.3 – Outer wall corner connection made with plaster, insulation and concrete

Table M.2 – Linear loss Ψ in W/mK at outward corners with plaster on insulation and light constructions (Interpolation is accepted)

Outer leaf Plaster, 10 mm Wind gypsum, 9 mm + covering, 0-20 mm

Wind gypsum, 9 mm + covering, 30-70 mm

Inner leaf Concrete, 125 mm Wooden frame work Wooden frame work

Insulation thickness, mm

220 -0,06

190 - 435 -0,05 -0,07

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Table M.3 – Linear loss Ψ in W/mK at ingoing corners for light constructions (Interpolation is accepted)

Outer leaf Plaster, 10 mm Wind gypsum, 9 mm + covering, 0-20 mm

Wind gypsum, 9 mm + covering, 30-70 mm

Inner leaf Concrete, 125 mm Wooden frame work Wooden frame work

Insulation thickness, mm

220 -0,02

190 - 435 -0,04 -0,06

By the light constructions the table covers the range up to a thickness of the covering of 70 mm. Is the thickness of the covering bigger than 70 mm, the linear loss can be determined from the formula: For outward corners:

Ψwith covering = Ψwithout covering - 2 dcovering Uwall For ingoing corners:

Ψwith covering = Ψwithout covering - 2 dcovering Uwall where

Ψwith covering is the linear loss with covering in W/mK Ψwithout covering is the linear loss calculated without covering (use table M.3 for wooden framework wall with 0-20 mm covering in W/mK dcovering is the thickness of the covering in m Uwall is the transmission coefficient of the outer wall in W/m2K.

M.1.3 Non-right-angeled corners By Non-right-angeled corner connections the size of the angle θ should be taken into account at the calculation of the linear loss. Figure M.4 and M.5 below show examples of outward and ingoing corners.

Figure M.4 – Angles for an outward corner (θ)

Figure M.5 – Angles for an ingoing corner (θ)

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At an angle θ bigger than 160o should be used outside measuring without deduction of linear loss. Is θ on 90o 10o the linear loss at 90o is used. At other angles θ, that is in the interval 45o – 80o or 100o – 160o below mentioned formula can be used. Alternatively can be made a detailed calculation. In table M.4 is added up the above mentioned guidelines.

Table M.4 – Determination of correction for angles between surfaces

Angle θ 45o < θ < 80o 80o < θ < 100o 100o < θ < 160o 160o < θ Outward inside

outside

inside

outside

inside

outside

inside

outside

Is calculated with below mentioned formula

Is calculated as 90o angle. The tables can be used

Is calculated with below mentioned formula

Is calculated as straight wall. No linear loss

Ingoing inside

outside

inside

outside

inside

outside

inside

outside

Is calculated with below mentioned formula

Is calculated as 90o angle. The tables can be used

Is calculated with below mentioned formula

Is calculated as straight wall. No linear loss

The linear loss at the angle θ can be determined from:

where θ is the angle (in degrees) between the surfaces of the two walls as shown in figure M.4 and M.5 Ψ(θ) is the linear loss W/mK at the angle θ Ψ(90o) is the linear loss W/mK, when the two walls are perpendicular to each other.

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M.2 Wall – roof connection

M.2.1 Outer wall and horizontal ceiling

Figure M.6 – Example of wall-roof connection with slanting cutting of the insulation

The linear losses in below mentioned table M.5 and M.6 is calculated without cutting of the insulation.

Table M.5 – The linear loss Ψ in W/mK at wall-roof connection in dependence on construction and insulation thickness in wall- and roof construction

Thickness of insulation in wall

Outer leaf Concrete, bricks or light weight concrete Plaster

Inner leaf Concrete, bricks or light weight concrete Concrete

Ceiling insulation Ceiling insulation

240 mm 340 mm 435 mm 600 mm 240 mm 340 mm 435 mm

125 mm -0,08 -0,09 -0,10 -0,13

190 mm -0,07 -0,07 -0,08 -0,10

>= 290 mm -0,07 -0,06 -0,06 -0,06

220 mm -0,06 -0,06 -0,07

Precondition: The outer walls are heavy constructions (concrete, bricks or leight weight concrete) or plaster on insulation. Interpolation in the table is accepted.

Table M.6 - The linear loss Ψ in W/mK at connection between light outer wall construction and roof construction in dependence on construction and insulation thicknesses (Interpolation in the table is

accepted)

Outer leaf Wind gypsum, 9 mm + covering 0-20 mm Wind gypsum, 9 mm + covering 30-70 mm

Inner leaf 240 mm 340 mm 435 mm 240 mm 340 mm 435 mm

Insulation thickmess in wall

125 mm -0,07 -0,09 -0,11 -0,10 -0,11 -0,13

190 mm -0,06 -0,07 -0,08 -0,08 -0,09 -0,10

>= 290 mm -0,06 -0,06 -0,06 -0,07 -0,07 -0,07

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At the light constructions the table covers the range up yo a thickness of the covering of 70 mm. Is the thickness of the covering bigger than 70 mm, the linear loss can be determined from the formula:

Ψwith covering = Ψwithout covering - dcovering Uwall W/mK where

Ψwith covering is the linear loss with covering Ψwithout covering is the linear loss calculated without covering (use table M.6 for wooden framework wall with 0-20 mm covering dcovering is the thickness of the covering in m Uwall is the transmission coefficient of the outer wall in W/m2K.

Cutting of insulation

d1 Vertical cutting at outerside of wall insulation d2 Insulation thickness in ceiling construction, measured vertical d3 Insulation thickness above wall plate, measured vertical d4 Insulation thickness in wall, measured horizontal.

Figure M.7 – Cutting of insulation at wall-ceiling connection by roof slope of θ = 20o Cutting is taken into consideration according to following principles: Insignificant cutting-off (no correction for cutting-off) If the cutting-off (in figure M.7) vertically outside at wall insulation (d1) is smaller than the difference between the insulation thickness in the roof construction (d2) and the insulation thickness in the wall (d4), so that d1 < d2 - d4, no correction for cutting-off will happen. Alternatively correction can for cutting-off be left out, if the following condition is fulfilled:

d1<=kd2 k is a reduction factor, that can be found from: Roof slope, θ (o) 15 20 30 45 60 75

Factor k 0,23 0,30 0,42 0,59 0,73 0,87

θ is the roof slope, that corresponds the slope of the top side of the insulation (figure M.8 illustrates, how the slope is measured).

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Cutting-off, where a negative linear loss can be obtained If there at least is 140 mm insulation vertically over wall plate (d3) and 140 mm of insulation in outer wall (d4), the linear loss on Ψ=0 W/mK can be used (that is external measure without deduction from the linear loss). Is the insulation thickness this place smaller, a separately detailed calculation should be made. These guidelines can also be expressed in table form:

Table M.7 – Correction for cutting of insulation Vertical cutting outside at wall insulation

Smaller than the difference in thickness of insulation in roof construction and in wall Smaller than thickness of insulation in roof construction multiplied with the reduction factor k

Use calculated without correction Use calculated without correction

Insulation at wall plate Insulation thickness horizontal at and vertical over the wall plate both bigger than 140 mm

Assumed 0 W/mK

Other cases Separate, detailed calculation

M.2.2 Sloping ceiling and outer wall

θ is the roof slope in degrees. The angle is negative by slope away from the connection.

Figure M.8 – Roof slope θ Is the linear loss of the construction connection with horizontal roof construction known, a correction for roof slope can be made:

where Ψ(θ) is the linear loss at the roof slope θ (W/mK) Ψ(0o) is the linear loss for wall-ceiling connection with horizontal insulation (W/mK).

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M.3 Battlement Battlement solutions with solely penetration of wood can be covered by the values calculated at wall-roof connection (section M.2).

1. Room (inside) 2. Internal wall 3. Leight weight concrete

Figure M.9 – Battlement with leight weight concrete in inner leaf next to ceiling insulation Below is calculated for battlement with and without leight weight concrete (figure M.9): Table M.8 – The linear loss at battlement in W/mK with and without leight weight concrete next to ceiling

insulation (Interpolation in the table is accepted)

Thickness of insulation in wall

Inner leaf Brick with insulating bricks Brick without insulating bricks

Ceiling insulation Ceiling insulation

240 mm 340 mm 435 mm 240 mm 340 mm 435 mm

125 mm 0,00 -0,04 -0,06 0,03 0,00 -0,03

190 mm -0,01 -0,02 -0,04 0,04 0,02 0,00

>= 290 mm 0,00 -0,01 -0,02 0,04 0,03 0,02

Is the inner leaf of through-going concrete, a linear loss of 0,29 W/mK can be used.

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M.4 Vertical apartment division/ceiling

1. Room (inside) 2. Internal wall 3. Leight weight concrete Figure M.10 – Apartment division with leight weight concrete in the wall next to the horizontal insulation

in the ceiling

1. Room (inside) 2. Internal wall 3. Leight weight concrete Figure M.11 - Apartment division with leight weight concrete and insulation next to and in a height of 50

cm above horizontal ceiling insulation

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Total linear loss in W/mK through vertical apartment division with 2 vertical brick walls (108 mm) cen be determined from below mentioned tables (supplement proportional to U-values of roof construction).

Table M.9 – Brick wall without light weight concrete (Interpolation in the table is accepted)

Insulation thickness in apartment division Insulation thickness in ceiling construction Linear loss W/mK 70 mm 145 + 95 mm 0,23

100 mm 145 + 195 mm 0,19

125 mm 145 + 145 + 145 mm 0,17

Table M.10 – Brick wall with light weight concrete next to horizontal insulation (figure M.10)

(Interpolation in the table is accepted)

Insulation thickness in apartment division Insulation thickness in ceiling construction Linear loss W/mK

70 mm 145 + 95 mm 0,13

100 mm 145 + 195 mm 0,11

125 mm 145 + 145 + 145 mm 0,10

Table M.11 – Brick wall with light weight concrete and 100 mm insulation next to and up to 50 cm hight above top side of horizontal insulation (figure M.11) (Interpolation in the table is accepted)

Insulation thickness in apartment division Insulation thickness in ceiling construction Linear loss W/mK

70 mm 145 + 95 mm 0,07

100 mm 145 + 195 mm 0,06

125 mm 145 + 145 + 145 mm 0,06

M.5 Example

In the following is shown an example of calculation of the heat loss at corner connections by the skylight shafts for the two skylights, as shown in annex L, figure L.2. Corner connection at skylight shafts The connections between the skylight shaft’s sides are outward corners with 90o angle. Insulation thickness = 240 mm Linear loss: (table M.1) = -0,07 W/mK Length: (2,1 m + 0,9 m) 4 = 12 m Temperature difference = 32 K Heat loss: -0,07 W/mK 12m 32K = -26,9 W Horizontal connection between ceiling and sides in light shaft Insulation thickness in light shaft = 240 mm Insulation thickness in ceiling: = 365 mm In-going corners. 3 sides in each skylight shaft with 90o angle. Linear loss: (table M.1) Ψ(90o) = 0,06 W/mK Length: (0,78 m + 2 2,1 m) 2 = 9,96 m

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In-going corners. 1 side in each skylight shaft with length 0,78 m and 120o angle. Linear loss at 90o (table M.1): Ψ(90o) = 0,06 W/mK Linear loss at 120o: Ψ(120o)= Ψ(90o) tan((180o-120o)/2) = 0,03 W/mK Length: 0,78 m 2 = 1,56 m Heat loss: (9,96 m 0,06 W/mK + 1,56 m 0,03 W/mK) 32K = 20,6 W It's on the right side not to include the linear loss at these in- and outward corners, since totally is managed a deduction in the heat loss.

M.6 Geometry and thermal conductivity Following values (table M.12) for the constructions are used in annex M.

Table M.12 – Thicknesses and thermal conductivities for the used materials

Material Thickness mm

Thermal conductivity W/mK

Plaster board 2 x 13 0,250

Wood 0,130 Insulation 0,037

Insulation in wood 45 per 82 cm 0,042

Leight weight concrete at heavy constructions 100 0,300

Leight weight concrete 100 0,300

Brick, inside 108 0,620

Brick, outside 108 0,730

Concrete, inside 125 1,900 Concrete, outside 80 2,000

Wind gypsum 9 0,250

Plaster 10 1,050

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Annex N (informative)

Determination of the transmission coefficient Ug for panes in existing buildings From figure N.1-N.4 the transmission coefficient Ug for different types of panes can be determined in depend-ence on the glass distance G. The figures can be used at conversion and renovation of existing buildings. All four figures apply to: Curve A is for a two layer pane Curve B is for a three layer pane L is for a vertical pane 45o is for a pane with 45o slope V is for a horizontal pane. For the actual pane slope is used the curve, that is nearest.

Figure N.1 – Panes with ordinary air and without covering on the glass

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Figure N.2 – Panes with 90% argon filling and low emission covering on the glass with normal emission 0,20. The two layer pane is assumed to have a low emission covering against the cavity, and the three layer pane is assumed to have 2 low emission coverings, one against each cavity. For two layer glass

with distance of more than 20 mm and without argon filling Ug is 0,25 W/m2K higher.

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Figure N.3 – Panes with 90% crypton filling and low emission covering on the glass with normal emis-sion 0,20. The low emission coverings are assumed placed as shown I figure N.2

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Figure N.4 – Panes with 90% xenon filling and low emission covering on the glass with normal emission 0,20. The low emission coverings are assumed placed as shown in figure N.2