Thermal Efficiency Standards in New Dwellings A guide to Approved Document L1A 2013 (England)

Transcription

1 CI/SfB (M2) Uniclass L6815 Residential New Build April 2014 Thermal Efficiency Standards in New Dwellings A guide to Approved Document L1A 2013 (England)

2 Contents Topic Introduction 3 Complying with ADL1A using SAP One Fabric Elemental Receipe for all house types 7 Party wall thermal by-pass 8 Pitched roof solutions 10 External wall solutions 12 Flooring solutions 18 How Knauf Insulation can help 21 Glossary 22 Energy performance certificates 23

3 Ho Introduction Main changes in Approved Document L1A 2013 The 2013 version of Approved Document L1A (conservation of fuel and power in new dwellings) came into effect (in England only) on 6th April CO 2 emissions The headline change is a 6% reduction in the carbon dioxide emissions from the mix of new dwellings relative to Approved Document L1A 2010 and is a step closer to the Governments aim of building zero carbon homes by The measurement of both the thermal performance and CO 2 emissions associated with the dwelling under consideration will be calculated using the 2012 version of the Standard Assessment Procedure (SAP 2012). Fabric energy efficiency A new addition to ADL1A is the introduction of a Target Fabric Energy Efficiency standard (TFEE). The TFEE accounts for a dwelling s combined annual heating and cooling load measured in kwh/m 2, for which a limit is set by SAP based on the performance of a notional dwelling of the same size and shape as that being assessed. The notional dwelling has fixed values for the fabric performance (U-values, thermal bridging, air leakage etc) as detailed in Appendix R of SAP A 15% increase is then added to the TFEE, giving the designer some additional design flexibility. When a new dwelling is built in line with the reference specification it will meet the carbon emissions and fabric energy efficiency requirements of ADL1A. High efficiency alternative systems Before construction of a new building starts, the person who is to carry out the work must analyse and take into account the technical, environmental and economic feasibility of using high-efficiency alternative systems (such as the following systems) in the construction, if available: (a) Decentralised energy supply systems based on energy from renewable sources (b) Cogeneration (Combined Heat and Power) (c) District or block heating or cooling, particularly where it is based entirely or partially on energy from renewable sources (d) Heat pumps There is no need to install any of the above measures as they may have been found to be impractical (due to size or location of site for instance) or that none of the measures was cost effective however, developers need to provide a report to show that they have been considered. Limiting U-values The limiting elemental fabric U-values remain as they were in ADL1A However, in practice a much more thermally efficient fabric will have to be specified in order to meet the Target Fabric Energy Efficiency (TFEE) rate see page 7 for Knauf Insulation s elemental fabric recipe. Limiting fabric parameters - Part L1A Element U-value (W/m 2 k) U-value (W/m 2 k) Roof Wall Floor Partywall Swimming pool basin Windows, rooflights and doors Air permeability 10.00m 3 /h/m 10.00m 3 /h/m Technical Support Team Tel:

4 Main changes in SAP 2012 Regional variations Wind speed has an impact on ventilation, exposure and wind turbines Allowance for height above sea level included in external temperature data Solar radiation effects solar gains and performance of renewable technologies Emission factors (CO 2/kWhr) Small increase for electricity and a bigger increase for gas and oil Fuel factors Fuel price and primary energy factors have been revised Others Increase in number of thermal bridges to be considered Increased options for heat loss from primary hot water pipes Target Fabric Energy Efficiency (TFEE) A new addition to ADL1A is the introduction of a Target Fabric Energy Efficiency standard (TFEE). The TFEE accounts for a dwelling s combined, annual heating and cooling load measured in kwh/m 2, for which a limit is set by SAP based on the performance of a notional dwelling of the same size and shape as that being assessed. The notional dwelling has fixed values for the fabric performance (U-values, thermal bridging, air leakage etc.) as detailed in Appendix R of SAP 2012 a 15% increase is then added to the TFEE, giving the designer some additional design flexibility. When a new dwelling is built in line with the reference specification it will meet the carbon emissions and fabric energy efficiency requirements of ADL1A. However, compliance with the TFEE standard can easily be achieved by adopting fabric U-values other than those referred to in Appendix R. Fabric First why exceed minimum requirements Part L of the Building Regulations sets minimum standards for the thermal performance of the building fabric elements (roof, wall, floor, windows and doors) by reference to limiting U-values. However, it should be remembered that this is the minimum level of performance required so why settle for this when a much more efficient insulated fabric can quite easily be achieved and delivers many long term associated benefits such as: reduced energy bills reduced CO 2 emissions reduced reliance on renewable technologies more comfortable internal environment with less temperature fluctuations Forward thinking developers could take the approach of amending their designs now and adopting a highly insulated fabric which would result in future requirements being met by renewable technologies being simply bolted on to their existing designs. It is worth remembering that if the renewable technologies fail, are not adequately maintained or suffer from reduced performance over time a well insulated dwelling will still provide a highly efficient fabric which requires no maintenance in order to deliver its thermal performance and it s there for the lifetime of the dwelling. Revised guidance for minimising thermal bridging Four ways of showing compliance: 1. Adopt DCLG Approved Construction Details 2. Adopt details calculated by a person with suitable expertise and experience - BRE Report BR Default values from Table K1 in SAP Use default `Y` value of 0.15W/m 2 K rather than individual psi values The quality assured construction details schemes proposed in ADL1A 2010 have been dropped Thermal bridging The size of a thermal bridge is determined by its thermal transmittance value (psi value) whilst the ability of a thermal bridge to prevent surface condensation from forming is determined by its temperature factor (f-factor). The overall impact of thermal bridging on a dwelling is determined by the Y-value which is calculated by dividing the total area of the external elements of the dwelling by the sum of the length and psi value of each thermal bridge. There is a significant increase in the number of highly insulated dwellings due to the ever more stringent regulatory requirements for the reduction of heat loss and CO 2 emissions from dwellings and this is something which will increase greatly as we move towards zero carbon new dwellings in One impact of highly insulated dwellings is the increased contribution to the overall heat loss from the dwelling due to the impact of thermal bridges (two or three dimensional) to the degree that it is now more vital than ever that good design detailing and on-site construction practises are employed to ensure that heat loss through the junctions of building elements and around openings is kept to a minimum. Along with the need to minimise heat loss through thermal bridges there is the secondary requirement to keep the surface temperature of the internal surface of the building fabric above a minimum level in order to prevent surface condensation and mould growth from occurring, thereby helping to maintain a healthy internal environment and also prevent deterioration of the building fabric. The thermal bridges detailed in the table below have been compiled by Knauf Insulation experts and all have an f-factor in excess of 0.75 which is sufficient to prevent surface condensation from forming in dwellings. The table below details the psi values applicable to each junction assigned to the house types on page 7.

5 Psi Values Ψ The psi value tables below indicate which junction descriptor to select when creating SAP calculations. If specifying (and building) Knauf Insulation construction details and calculated Psi values the whole house Y-value can be considerably reduced thereby, assisting compliance with the carbon emission and Target Fabric Energy Efficiency requirements of Approved Document L1A. The specification of Knauf Insulation Psi values and construction details will have a positive influence on the thermal performance of the building by significantly reducing heat loss through junctions and openings, especially when compared to the most Psi values referenced in Appendices K and R of SAP 2012 Junctions with an external wall Appendix K Psi values from SAP 2012 Reference values of Psi for junctions (England) Knauf Insulation calculated Psi values Approved Default Table R2 Junction detail Ψ Ψ Ψ Ψ (W/mK) (W/mK) (W/mK) (W/mK) E2 Other lintels (including other steel lintels) E3 Sill E4 Jamb E5 Ground floor (normal) E6 Intermediate floor within a dwelling E10 Eaves (insulation at ceiling level) E12 Gable (insulation at ceiling level) E13 Gable (insulation at rafter level) E16 Corner (normal) Detail reference E17 Corner (inverted - internal area greater than external area) E18 Party wall between dwellings c) D modelling The calculation of linear thermal transmittance (Ψ) and the temperature factor (f-factor) need to be based on the 2-D modelling techniques described in BRE Information Paper IP 1/06, Assessing the effects of thermal bridging at junctions and around openings in the external elements of buildings and BR 497, Conventions for calculating linear thermal transmittance and temperature factors. The analysis of an eaves detail below assumes the following: 400mm Loft Roll 44 Aircrete block inner leaf (λ = 0.15 W/mK) External cavity fully filled with 100mm Supafil 34 (λ = W/m 2 K) Junction detail Junctions with a party wall c) P2 Intermediate floor within a dwelling N/A P4 Roof (insulation at ceiling level) N/A P5 Roof (insulation at rafter level) N/A R1 Head N/A N/A R2 Sill N/A N/A R3 Jamb N/A N/A Junctions within R4 Ridge (vaulted ceiling) N/A N/A a roof or with a R5 Ridge (inverted) N/A N/A room-in-roof R6 Flat ceiling N/A N/A R7 Flat ceiling (inverted) N/A N/A R8 Roof wall (rafter) N/A N/A R9 Roof wall (flat ceiling) N/A N/A c) Value of Ψ is applied to each dwelling Temperature distribution Linear thermal transmittance y = Temperature factor f = Technical Support Team Tel:

6 How to comply with ADL1A using SAP 2012 Whole-house specifications one elemental recipe for all house types The following specifications show how, for a range of typical dwelling types, it is possible to meet the CO2 emission and Fabric Energy Efficiency requirements of Approved Document L1A 2013 using forms of construction with reasonably achievable U-values, without the need for mechanical ventilation or new low-energy technologies. The specifications have been devised using the SAP 2012 methodology, using U-values appropriate to the use of Knauf Insulation products and making reasonable assumptions about other aspects of the design, e.g. air permeability rates and the type of space heating see Tables below. Five typical dwelling types have been analysed, some with mid and end-terrace variants. The U-values for each element of the dwelling are shown on the diagram opposite, together with cross references to the relevant elemental solutions tables. U-value specifications Other building element specification results Dwelling type Storeys Roof U-value Wall U-value Floor U-value Sloped roof U-value Party wall U-value Dormer roof U-value Dormer wall U-value Window U-value Door U-value Boiler efficiency (%) Air permeability Thermal bridging Thermal mass TER DER TFEE DFEE Pass/Fail End terrace - 3 bedrooms n/a Zero n/a n/a Pass Mid terrace - 3 bedrooms n/a Zero n/a n/a Pass Detached - 4 bedrooms n/a Zero n/a n/a Pass End terrace two and a half storey - 3 bedrooms Zero Pass Mid terrace two and a half storey - 3 bedrooms Zero Pass Standard parameters for all dwelling types Parameter Value Ventilation Natural Low energy lighting 100% For project specific calculations contact our Technical Support Team on

7 One fabric Elemental Recipe for all house types 100mm DriTherm Cavity Slab 34 Super or Supafil 34 75mm or 100mm Masonry Party Wall Slab or Supafil Party Wall Masonry cavity wall - fully filled Block W/mK U-value W/m 2 K Masonry party wall - fully filled Effective U-value of zero 150mm or 200mm* Polyfoam ECO Floorboard Standard 140mm FrameTherm mm and 300mm** Loft Roll 44 Ground bearing concrete floor U-value W/m 2 K Timber frame wall U-value W/m 2 K Loft insulation U-value W/m 2 K SAP standard parameters for all dwelling types Element U-value (W/m 2 K) Page No Parameter Value Roof - ceiling level Party wall effective U-value Zero Roof - rafter level Thermal bridging External walls Air permeability (m 3 /hr per m 2 ) 5.00 Ground floor Ventilation Natural Windows 1.30 Low energy lighting 100% Doors 1.20 Gas condensing boiler efficiency (%) *Dependent on P/A ratio **(2 x 150mm over joists) Technical Support Team Tel:

8 Solutions to party wall bypass Research headed by Leeds Metropolitan University, MIMA (the Mineral Wool Insulation Manufacturers Trade Association) and Knauf Insulation has confirmed that an effective zero U-value can be achieved by fully filling the cavity of a masonry wall with glass mineral wool of a minimum 18kg/m3 density and placing a sleeved flexible cavity barrier at the junction of the party wall with external elements. Junctions of party walls with external walls E-WM-22 masonry party wall with plasterboard on dabs Additionally, if the cavity is fully filled, this may have implications for sound transmission and the ability to meet the requirements of Part E. With this in mind, developers can now adopt a Knauf Insulation Robust Detail as follows: E-WM-22 - built in solution with Masonry Party Wall Slab E-WM-28 - blown in solution with Supafil Party Wall E-WT-2 - built in solution with Timber Frame Party Wall Slab Robust Detail t an Compli External wall cavity fully filled with Supafil or DriTherm Cavity Slabs Cavity barrier Party wall cavity fully filled with 100mm Masonry Party Wall Slab Plasterboard on dabs (no parge coat) Junctions of party walls with external walls E-WM-28 masonry party wall with plasterboard on dabs External wall cavity fully filled with Supafil or DriTherm Cavity Slabs Cavity barrier Party wall cavity fully filled with Supafil Party Wall Plasterboard on dabs (no parge coat) Junctions of party walls with external walls E-WT-2 timber frame party wall with sheathing board FrameTherm in external walls Cavity barrier Party wall cavity fully filled with Timber Frame Party Wall Slab FrameTherm 40 2 or more layers of plasterboard Sheathing Board Robust Detail t an Compli

9 Table 1 Robust Detail Separating Walls and Party Wall Bypass Solutions Robust Detail Minimum Cavity Block Density Zero Supafil Masonry Block Type Wall Finish Parge coat CfSH Credits Wall Type Width (mm) (kg/m 3 ) U-value Party Wall Party Wall Slab E-WM-1 75 Dense 1850 to 2300 Wet plaster Yes 0 Yes 3 3 E-WM-2 75 Light aggregate 1350 to 1600 Wet plaster Yes 1 Yes 3 3 E-WM-3 75 Dense 1850 to 2300 Plasterboard on dabs Yes 1 Yes 3 3 E-WM-4 75 Light aggregate 1350 to 1600 Plasterboard on dabs Yes 1 Yes 3 3 E-WM-5 75 Besblock 1528 Plasterboard on dabs on cement render Yes 1 Yes 3 3 E-WM-6 75 Aircrete 600 to 800 Plasterboard on dabs Yes 1 Yes 3 3 E-WM Aircrete - thin joint 600 to 800 Plasterboard on dabs on cement render Yes 0 Yes 3 3 E-WM Light aggregate 1350 to 1600 Plasterboard on dabs Yes 3 Yes 3 3 E-WM Aircrete - thin joint 600 to 800 Plasterboard on dabs on cement render Yes 3 Yes 3 3 E-WM Dense 1850 to 2300 Plasterboard on dabs Yes 3 Yes 3 3 E-WM Dense 1850 to 2300 Wet plaster Yes 3 Yes 3 3 E-WM Dense or light aggregate 1350 to 1600 or 1850 to 2300 Plasterboard on dabs on cement render Yes 4 Yes 3 3 E-WM Light aggregate 1350 to 1600 Wet plaster Yes 3 Yes 3 3 E-WM Light aggregate 1350 to 1600 Plasterboard on dabs No 3 Yes 3 E-WM Porotherm n/a Plasterboard on dabs Yes 3 Yes 3 E-WM Besblock 1528 Plasterboard on dabs No 1 Yes 3 E-WM Light aggregate 1350 to 1600 Plasterboard on dabs No 3 Yes 3 Timber Frame Robust Detail Wall Type Minimum Cavity Width (mm) Sheathing Wall Finish External (flanking) wall CfSH Credits Zero U-value E-WT mm(min) thick board 2 or more layers of gypsum-based board Outer leaf masonry-min 50mm cavity Eathwool Timber Frame Party Wall Slab 1 Yes 3 The party wall bypass mechanism This is a process whereby heat is lost to an open party wall cavity containing cold air which has entered from the external flanking building elements, mainly external walls. In fact, heat is lost from both sides of the party wall to the external environment, the extent being affected by external climatic conditions and stack effect within the party wall cavity. It is important to be aware that, where heated spaces extend into the loft, there is also a potential thermal by-pass where the party wall meets the roof covering. Although the thermal bypass is expressed as a U-value, it is not a U-value in the normal sense because the heat loss mechanism is a combination of heat loss effects, e.g. through the party walls, by air circulation from the party wall cavity to other building cavities and, finally, to the external environment. The importance of zero U-values and complying with ADL1A ADL1A states that, in the absence of specific independent scientific field evidence, it is reasonable to apply indicative U-values (see Table 2 ), provided that any edge sealing is aligned with the thermal insulation in adjacent external elements. Within ADL1A the notional building, which is used to calculate the Target Emission Rate (TER), includes a party wall heat loss of zero. Clearly, using a construction option with an effective U-value of more than zero will result in an increase in the Dwelling Emission Rate (DER) making it more difficult to achieve the ADL1A carbon emissions standards. The difference between adopting a zero effective U-value for the party wall and leaving the cavity unfilled, and with no effective edge sealing can result in an increase in the Dwelling Emission Rate (DER) of up to 15% for a typical end terrace house. So clearly, there is a significant advantage in adopting a zero U-value solution, this will become even more important as we approach 2016 and the requirement to build zero carbon homes. Table 2 U-values for party walls Wall construction U-value (W/m 2 K) Solid 0.00 Unfilled cavity with no effective edge sealing 0.50 Unfilled cavity with effective edge sealing around all edges and in line with insulation layers in abutting elements Fully filled cavity with effective edge sealing around all edges and in line with insulation layers in abutting elements Technical Support Team Tel:

10 Pitched roof solutions The impact of heat loss through roofs The roof comprises a large percentage of the external shell of most dwellings and is a key interface between the internal and external environment. Usually, the most exposed surface of the building, the roof, must not only be weather-tight and waterproof, but also must be well insulated to minimise heat loss. Without loft insulation, as much as 25% of a house s heating costs could be attributed to heat lost through the roof. Loft insulation acts as a blanket, trapping heat rising from below. It is a simple and effective way to reduce heating bills. Installing Loft Rolls delivers thermal, acoustic and fire resistance benefits to any roof, as well as being the most cost-effective solution for insulating a pitched roof at ceiling level. Pitched roof solutions The following pages include solutions for roofs insulated both at ceiling level and at rafter level. Whilst both types of roof are required to provide high standards of thermal insulation, roofs at rafter level should also be designed to provide protection from noise. In this case noise from road traffic and airplanes, rainfall drumming on the roof and flanking sounds from attached properties could cause considerable nuisance within the rooms created in the roof void. BBA U-value Competency Scheme All U-values referred to in this publication have been compiled in accordance with the BBA/TIMSA U-value Competency Scheme. For project specific calculations contact our Technical Support Team on

11 Table 3 Ceiling level between and above joists Insulation over ceiling Insulation thickness (mm) Between joists Over joists Typical U-values (W/m 2 K) (3x150) (2x200) 0.09 Loft Roll (2x170) (2x150) 0.11 U-value (2x200) (2x150) 0.10 Loft Roll Joist sizes assumed to be 100x48mm at 600mm centres (8% bridging plus 1% for cross noggings). Non-combustible products with the highest Euroclass A1 rating Products have an A+ generic Green Guide rating Zero ODP and GWP rated products Products are compression packed to reduce transport related CO 2 emissions Product manufacture has a very low environmental impact Glass mineral wool insulation products provide the lowest cost solution for insulating a roof Suitable for use with traditional and vapour permeable roofing membranes Table 4 Rafter level between and below rafters Rafter Depth (mm) Rafter Roll Insulation thickness between rafters (mm) Knauf PIR Laminate* thickness below rafters (mm) U-value Rafter depth equals Rafter Roll thickness plus 25mm unventilated airspace. Rafters are 38mm at 600mm centres (bridge of 6.33%). Plasterboard facing on Knauf PIR Laminate is 9.50mm (λ = 0.210). *Available from Knauf Drywall. Achieves low U-values even with shallow rafters Rafter Roll is compressible so it is easy to friction fit tightly between rafters and avoid cold air penetration Significantly improves the acoustic performance of the roof Can be used along with an extra layer of plasterboard to satisfy the requirements of Robust Details to resist flanking sound around separating walls Longer rolls with greater coverage per roll than equivalent products Table 5 Dwarf walls in pitched roofs Rafter Roll Knauf PIR Laminate* thickness on face of timber studs (mm) Plasterboard facing on Polyfoam Linerboard is 9.50mm (λ = 0.210). Plasterboard facing on Knauf PIR Laminate is 9.50mm (λ = 0.210). Timber stud depth equals insulation thickness (bridge of 7.83%). Additional airspace resistance of 0.50 m 2 K/W. *Available from Knauf Drywall. Achieves low U-values even with shallow rafters Rafter Roll is compressible so it is easy to friction fit tightly between rafters and avoid cold air penetration Significantly improves the acoustic performance of the roof Can be used along with an extra layer of plasterboard to satisfy the requirements of Robust Details to resist flanking sound around separating walls Longer rolls with greater coverage per roll than equivalent products Technical Support Team Tel:

12 External wall solutions The impact of heat loss through external walls The greatest proportion of heat loss from a typical house, as much as 35%, is through the walls, mainly because of their large area. Installing thermal insulation slows down the rate of heat loss, thereby giving immediate savings on fuel bills. Providing an efficient building envelope is vitally important in meeting the requirements of ADL1A of the Building Regulations and achieving the higher Code levels of the Code for Sustainable Homes. Innovation driving change Partial cavity fill and insulated dry linings, for example, are likely to become less popular as thermal insulation values rise, with full fill masonry cavity walls and highly insulated timber framed walls being able to achieve improved U-values using slightly wider cavities and deeper timber studs. There is likely to be greater innovation in other forms of construction, especially where rainscreen cladding is used to protect the insulation layer. The recent tightening of thermal regulations has placed a greater emphasis on avoiding thermal bridging and ensuring an airtight external envelope. As a result, detailing at junctions is likely to become more complex and sophisticated. On the following pages we explore a number of innovative constructions which maximise thermal and, where appropriate, acoustic performance. BBA U-value Competency Scheme All U-values referred to in this publication have been compiled in accordance with the BBA/TIMSA U-value Competency Scheme. For project specific calculations contact our Technical Support Team on

13 Table 6 Masonry cavity walls full fill with built-in glass mineral wool Insulation thickness (mm) Lightweight aircrete (λ=0.11) DriTherm 32 Ultimate Brick outer leaf/cavity/100mm block inner leaf and plasterboard on dabs Standard aircrete (λ=0.15) High strength aircrete (λ=0.19) Lightweight aggregate (λ=0.28) Medium density (λ=0.45) U-value ( ) (100+75) (75+75) DriTherm 34 Super 200 ( ) (100+75) (100+50) DriTherm 37 Standard 200 ( ) (100+75) (100+50) Block sizes are assumed to be 440 x 215mm, with 10mm mortar joints. Wall ties are assumed to be stainless steel with a cross-sectional area of no more than 12.5mm 2 for structural cavities up to 150mm wide and two part wall ties with a cross-sectional area of 25mm 2 for larger cavities. U-values are based on an internal finish of 12.5mm plasterboard (λ =0.210 W/mK) on dabs. DriTherm Cavity Slabs have an A+ generic Green Guide rating Non-combustible products with the highest Euroclass A1 rating DriTherm Cavity Slabs are the lowest cost, built-in solution, for masonry cavity walls No requirement for fire stops as all DriTherm products are completely non-combustible and fully fill the cavity No requirement for acoustic cavity stops at junctions with separating floors and walls Products are robust and resilient making them easy to handle, store on site and install Formally guaranteed for 50 years to resist the transmission of liquid water and retain their thermal performance 35 year proven performance All products have British Board of Agrément Certification for all exposure zones Technical Support Team Tel:

14 External wall solutions (continued) Table 7 Masonry cavity wall full fill with injected glass wool Insulation thickness (mm) Supafil 34 Lightweight aircrete (λ=0.11) Brick outer leaf/cavity/100mm block inner leaf and plasterboard on dabs Standard aircrete (λ=0.15) High strength aircrete (λ=0.19) Lightweight aggregate (λ=0.28) Medium density (λ=0.45) U-value Supafil Supafil products have an A+ generic Green Guide rating Non-combustible products with the highest Euroclass A1 rating Suitable for any cavity width No waste on site Installed by approved contractor British Board of Agrément Certification for all exposure zones Product guaranteed to resist moisture penetration Wall construction quicker than with built-in cavity wall insulation Installed after wall constructed when building is watertight Block sizes are assumed to be 440 x 215mm, with 10mm mortar joints. Wall ties are assumed to be stainless steel with a cross-sectional area of no more than 12.5mm 2 for structural cavities up to 150mm wide and two part wall ties with a cross-sectional area of 25mm 2 for larger cavities. U-values are based on an internal finish of 12.5mm plasterboard (λ = W/mK) on dabs. For project specific calculations contact our Technical Support Team on

15 External wall solutions (continued) Table 8 Timber frame wall single layer insulation between studs With standard breather membrane Insuation thickness of 140mm Masonry outer leaf Tile/timber clad outer leaf FrameTherm FrameTherm FrameTherm U-value FrameTherm With Low-E breather membrane FrameTherm FrameTherm FrameTherm FrameTherm Non-combustible products with the highest Euroclass A1 rating FrameTherm products have an A+ generic Green Guide rating Products are compression packed to reduce transport related CO 2 emissions Lightweight and easier to cut and handle than rigid foam boards Much faster to install than rigid boards, which require very accurate cutting Products are compressible, and friction fit between timber studs avoiding cold bridging at joints Improves the acoustic performance of the wall Table 9 Timber frame wall single layer insulation between studs with a low e service void Insuation thickness (mm) FrameTherm 32 Masonry outer leaf with Low-E breather membrane Masonry outer leaf with standard breather membrane Tile/timber clad outer leaf U-value FrameTherm FrameTherm FrameTherm All the advantages of using Frametherm in the application above apply Provides a service void helping to preserve the integrity of the vapour control layer Improves the thermal performance of timber frame walls within a standard stud width Achieves low U-values in a 90mm stud Technical Support Team Tel:

16 External wall solutions (continued) Table 10 Timber frame single layer blowing wool system U-value Supafil Frame and standard breather membrane Supafil Frame and Low-E breather membrane Insulation thickness (mm) Masonry outer leaf Tile/timber clad outer leaf Non-combustible products with the highest Euroclass A1 rating Supafil Frame has an A+ generic Green Guide rating No waste on site Completely fills all gaps, voids and hard to reach areas around services Installation is quick and clean, without adhesives or added moisture Blown from the inside of the dwelling 09/4629 Table 11 Timber frame insulation between studs and to exterior of sheathing board U-value Timber studs filled with: FrameTherm 32 FrameTherm 35 FrameTherm 40 Timber studs filled with: FrameTherm 32 FrameTherm 35 FrameTherm 40 Insulation thickness (mm) DriTherm 32 Ultimate outside sheathing, thickness (mm) Masonry outer leaf Low-E service void Insulation thickness (mm) Twin insulated full fill DriTherm 32 Ultimate outside sheathing, thickness (mm) Masonry outer leaf Low-E service void Non-combustible products with the highest Euroclass A1 rating Products have an A+ generic Green Guide rating Very low U-values can be achieved No need for fire stopping (full fill) Partial fill system accepted by NHBC FrameTherm is compressible and friction fits between timber studs avoiding cold bridging at joints The following applies to Tables 8, 9, 10 and 11: Timber frame bridging factor of 15% to account for studs, noggins and sole plates etc. Stud depth is taken to be the same as the thickness of insulation specified. Thermal conductivity of timber studs is 0.12 W/mK. Ventilated low emissivity external airspace has an R-value of 0.29 m 2 K/W. Unventilated low emissivity external cavity has an R-value of 0.77 m 2 K/W. Service void has an R-value of 0.78 m 2 K/W. For project specific calculations contact our Technical Support Team on

17 Table 12 Solid masonry walls external insulation 215mm solid block wall (λ = W/mK) 215mm solid block wall (λ = W/mK) plus insulation with the following λ values (W/mK): Insulation thickness (mm) External Wall Insulation System U-value / / U-values based on an internal finish of 12.5mm plasterboard (0.210 W/mK) on dot and dabs 0.038(W/mK) based on EWI Rock Slab and 0.032(W/mK) based on EWI EPS Slab. Rock mineral wool product is a non-combustible product with the highest Euroclass A1 rating Compression resistant insulation provides a high level of support to the render Lightweight and robust systems, advantageous where there are loading restrictions on the structure Water repellent systems Impact resistant solutions Efficient and quick to install Protects the fabric of the building Reduces thermal bridging Technical Support Team Tel:

18 Floor solutions Thermal performance The thermal performance of ground floors is determined by a combination of the thermal resistance of the floor construction, the shape of the floor and the insulation provided by the ground. BBA U-value Competency Scheme All U-values referred to in this publication have been compiled in accordance with the BBA/TIMSA U-value Competency Scheme. Table 13 Ground floor insulation below slab or under screed Insulation thickness (mm) Polyfoam ECO Floorboard Standard Ratio of perimeter (m) to area (m 2 ) (2 x 85mm) (2 x 75mm) U-value (2 x 65mm) (2 x 50mm) No account has been taken for the thermal performance of the concrete slab or screed. The ground is assumed to be clay with a thermal conductivity of 1.50 W/mK. Long term exposure to water has negligible impact on the thermal performance of Polyfoam ECO Floorboard Standard Can be used above or below the damp proof membrane (dpm) above dpm Polyfoam protects dpm from damage before and during the concrete pouring process, below the dpm Polyfoam protects the dpm from possible puncture from hardcore and extremes of temperature at perimeter Resists tough site conditions Industry leading compressive strength Can tolerate traffic from subsequent trades without damage prior to floor finish being laid Table 14 Ground floor Insulation above slab Ratio of perimeter (m) to area (m 2 ) Insulation thickness (mm) Thermal Floor Slab Plus 210 (3x70mm) (80+90mm) U-value (70+80mm) (60+70mm) The U-values have been calculated assuming a clay subsoil with a thermal conductivity of 1.50 W/mK. Non-combustible product with the highest Euroclass A1 rating Zero ODP and GWP rated product Will accommodate slight imperfections in sub floor High compressive strength Easy handling and fitting For project specific calculations contact our Technical Support Team on

19 Table 15 Ground floor Suspended beam and block floor with insulation below chipboard deck Insulation thickness (mm) Polyfoam ECO Floorboard Standard Ratio of perimeter (m) to area (m 2 ) (2 x 85mm) (2 x 75mm) U-value (2 x 65mm) (2 x 50mm) Concrete beams with aircrete blocks with a thermal conductivity of 0.15 W/mK. The ground is assumed to be clay with a thermal conductivity of 1.50 W/mK. Provides high thermal performance in limited insulation zone Structural and thermal solution Resistant to site damage Robust and can tolerate traffic from following trades without damage prior to floor finish being laid Table 16 Ground floor Suspended beam and block floor with insulation below screed Insulation thickness (mm) Polyfoam ECO Floorboard Standard Ratio of perimeter (m) to area (m 2 ) (2 x 85mm) (2 x 75mm) U-value (2 x 65mm) (2 x 50mm) Concrete beams with aircrete blocks with a thermal conductivity of 0.15 W/mK. No account has been taken of the thermal performance of the screed. The ground is assumed to be clay with a thermal conductivity of 1.50 W/mK. Compression resistant, supporting screed under high point loads Provides high thermal performance in limited insulation zone Structural and thermal solution Resistant to site damage Robust and can tolerate traffic from subsequent trades without damage prior to floor finish being laid Technical Support Team Tel:

20 Floor solutions (continued) Table 19 Ground floor Suspended timber floor with insulation between joists Insulation thickness (mm) 300 (2x150mm) ( mm) (2x100mm) U-value Loft Roll 44 Ratio of perimeter (m) to area (m 2 ) Non-combustible products with the highest Euroclass A1 rating Loft Roll is manufactured to suit standard joist spacing s Products friction fit between joists avoiding cold bridging at the joints Low cost solution Fast and simple solution Loft Roll ( mm) (2x100mm) Flexible Slab 250 ( mm) (2x100mm) The U-values have been calculated assuming 48mm wide joists at 600mm centres. Table 17 Exposed upper floor Insulation below concrete soffit U-value Insulation thickness (mm) Soffit Linerboard Standard Beam and block Dense Medium Lightweight Aircrete Precast concrete plank (150mm) Cast slabs (200mm) 165/ / Aesthetic finish Installed from below so no access to area above floor required Fully non-combustible solution Highest Euroclass A1 rating Can enhance acoustic performance of floor Table 18 Exposed upper floor Insulation between timber joists U-value Non-combustible products with the highest Euroclass A1 rating Insulation thickness (mm) 0.33* 0.25* 0.26* Loft Roll is manufactured to suit standard joist spacing s Products friction fit between joists Loft Roll avoiding cold bridging at the joints Low cost solution Fast and simple solution Flexible Slab *Additional thermal resistance for shelter effect of enclosed unheated spaces, Ru (m 2 K/W). The U-values have been calculated assuming joists are 48mm wide, spaced at 600mm centres and the same depth as the insulation. For project specific calculations contact our Technical Support Team on

21 How Knauf Insulation can help Technical Support Our Technical Support Team (TST) provides personal, high level technical support which includes our experienced team of advisors supplying U-value calculations, condensation analysis, SAP calculation assistance and assistance with CAD drawings and NBS clauses. Also available through the TST is the 3D finite element heat loss calculation service. For further information please call the TST on D heat loss calculation service Our Technical Support Team have the ability to provide 3D finite element heat loss calculations to fully comply with Part L of the Building Regulations. By analysing the heat flows through external wall construction elements (such as rainscreen cladding systems) TST can provide robust supporting evidence for U-value calculations. For further information please call TST on BBA/TIMSA U-value Competency Scheme Knauf Insulation is a fully accredited member of the prestigious and industry leading British Board of Agrément (BBA) U-value and Condensation Calculation Competency Scheme. The scheme aims to promote and assist accurate, objective and consistent calculation of U-values and condensation analysis within the UK construction industry. As a result, Knauf Insulation customers can be assured that the U-value and condensation calculations supplied to them (and contained in this publication) are in line with all relevant industry standards, accurate and consistent, and there is a clear and comprehensive audit trail in place. Project and Specification Managers Knauf Insulation has a team of Business Development Managers and Project and Specification Managers covering all parts of the country. Their role is to provide cost-effective solutions to specifiers of thermal insulation, acoustic insulation and fire protection. For more information please visit Building Information Modelling (BIM) Knauf have been leading a major delegation across Europe and the US on BIM for several years. We believe that the use of BIM will increase very quickly in the UK as its use will be compulsory on all Government funded projects by At Knauf Insulation we are fully committed to providing our customers with a complete range of specification support documentation including Building Information Modelling (BIM) materials and material layer sets (BIM Objects). We have produced a comprehensive library of BIM Objects to support the specification community and have ensured that they are readily available and compatible with a wide range of software programs including, Revit, ArchiCAD, Bentley and Vectorworks. In addition to providing BIM enabled objects and material layer sets we have also started a funded project working in collaboration with numerous market leading organisation s in order to manage a pilot scheme. The deliverable will be a case study for Government and a training scheme for 500+ individuals looking to develop BIM skills with a qualification recognised at NVQ level. This is a very exciting project and one that is being looked upon as vital to ensuring buy-in from all organization`s involved. Details of this program are available upon request. For our full BIM library please visit

22 Glossary of terms Approved Construction Details Approved Construction Details (ACDs) are details of junctions at openings at junctions between elements (such as a wall/floor junction) which have been formally recognised by the Department of Communities and Local Government. The details focus specifically on measures to minimise thermal bridging and air leakage, and each detail has an approved linear transmittance value which is listed in Table K1 of SAP They include a check list for recording compliance. DER The Dwelling Emission Rate (DER) is the CO 2 emission rate for the proposed dwelling. It is expressed in terms of kg/m 2 /yr. In practice, two DER calculations are needed; the first at the design stage, based on plans and specifications used in the submission to the Building Control and the second at the final stage of completion. The final calculation should be based on the dwelling as constructed, including any changes made since the design stage and the results of the air permeability test. EPBD The objective of the European Union Energy Performance Building Directive (EPBD) is to promote the improvement of energy performance of buildings within the Community taking into account outdoor climatic and local conditions, as well as indoor climate requirements and cost-effectiveness. All member countries must implement the Directive which has been updated in England is complying with the Directive through the application of Approved Document L and the requirement to issue Energy Performance Certificates. Fuel factor The fuel factor is used when calculating the Target Emission Rate (TER). The fuel factor takes into account the higher carbon emissions of fuels other than mains gas and is applied where the main form of heating for the proposed dwelling is not mains gas. The fuel factor has the effect of penalising fuels other than mains gas for the proposed dwelling. Where heating or hot water is to be provided by appliances having different fuels, the fuel used for the main heating system should be used in the TER calculation. The fuel factors are to be reviewed as progress is made towards zero carbon. In particular, where grid electricity is used for heat pumps, the fuel factor for heat pumps will be reviewed as the renewable heat incentive is introduced. The solid mineral fuel factor should be used where the appliance can only be used for that fuel, or where a solid multi-fuel appliance is being used in a Smoke Control Area. The solid multi-fuel fuel factor should only be used where the appliance is designed for that purpose and, in a Smoke Control Area, where the specific appliance has been approved for that use. Notional dwelling The notional dwelling is the benchmark dwelling design from which the Target Emission Rate (TER) is determined. It is of the same size and shape as the proposed dwelling constructed to the reference values detailed in Appendix R of SAP For the notional dwelling, the party wall heat loss is taken to be zero. Robust Details Previously, there were Robust Details for thermal and sound insulation. Those for thermal insulation became Approved Construction Details but those for sound insulation retained the Robust Details title. The Robust Details scheme provides an alternative to pre-completion testing for demonstrating compliance with the sound insulation performance standards of Part E of the Building Regulations for new dwellings. SAP 2012 The Government s Standard Assessment Procedure (SAP) is the method that must be used for calculating the CO 2 emission rate and Target Fabric Energy Efficiency Standard for new dwellings. It calculates the energy requirement for heating, hot water, ventilation and internal lighting for the dwelling. As well as giving the CO 2 emission rate in terms of kg/m 2 /yr, it also produces a SAP rating, on a scale from The SAP 2012 includes all the technical assumptions and rules for calculating the CO 2 emission rate and it includes the SAP worksheet. Software versions of the SAP calculation method are available from a number of sources. TER The Target CO 2 Emission Rate (TER) is the energy performance target that must be achieved by the proposed dwelling to comply with the requirements of the Approved Document. It is expressed in terms of kg/m 2 /yr. For the 2006 edition of the Approved Document, the TER represented a 20% improvement over the calculation for the notional dwelling with a 2002 specification. For the 2010 edition, the requirement is to make a further 25% saving over the 2006 TER, in effect making a 40% saving over the 2002 notional dwelling. TFEE`s The Target Fabric Energy efficiency Standard (TFEE) accounts for a dwelling s combined, annual heating and cooling load for which a limit is set by SAP based on the performance of a notional dwelling of the same size and shape as that being assessed, but with fixed values for the fabric performance e.g. U-values, thermal bridging, air leakage etc, a 15% margin is then added, giving the designer some additional design flexibility. TFEE equates to the amount of energy consumed in kilowatt-hours per square metre of floor area per year.