Building to Approved Document L with Aircrete

Transcription

1 Building to Approved Document L with Aircrete

2 Introduction Overview Methods of Compliance Other issues Solutions using H+H Celcon s blocks

3 What is the Government doing? Reducing CO 2 emissions Awareness of a need for Flexibility Eliminating technical risks Avoiding excessive cost

4 Overview Improved U-values and changes to EN calculation method Closer link between U-values and boiler efficiency New guidance has been developed with industry re robust construction details More flexibility on day lighting Some control on electric lighting Aiming for an air leakage standard

5 Overview Continued Move from SAP to Carbon emissions basis COLD BRIDGING, a calculation method as an alternative to robust details HEATING and HWS Controls virtually unchanged Commissioning/testing Approved contractor self-certify

6 Methods of Compliance Elemental Target U-value Carbon Index, replaces SAP but SAP is still needed

7 The Elemental Method Table 1: Elemental Method: u-values (W/m²K) for construction elements Exposed Element Pitched roof with insulation between rafters 1,2 Pitched roof with insulation between joists Flat roof 3 Wall Floor Windows, doors and rooflights 4 (area-weighted average), glazing in metal frames 5 Windows, doors and rooflights 4 (area-weighted average), glazing in wood or PVC frames 5 U-value Notes to Table 1: 1 Any part of a roof having a pitch of 70 or more can be considered as a wall. 2 For the sloping parts of a room-in-the-roof constructed as a material alteration, a U-value of 0.3 W/m²K would be reasonable 3 Roof pitch not exceeding 10 4 Rooflights include windows 5 The higher U-value for metal framed windows allows for additional solar gain due to the greater glazed proportion.

8 SEDBUK table for Target U-value Method Table 2: Minimum boiler SEDBUK to enable adoption of the U-values in Table 1, And reference boiler SEDBUK for use in the Target U-value Method Central heating system fuel SEDBUK % Mains natural gas 78 LPG Oil 80 85

9 The Elemental Approach This method does not provide maximum flexibility E.g. Maximum opening area of 25% of total floor area Nevertheless we do have solutions

10 The Target U-value Approach U T = [{ (A R /A T ) - 0.1(A GF /A T ) (A F /A T )} X f e ] +? S Where:- f e = Proposed boiler SEDBUK (%) Reference boiler SEDBUK (%)? S = 0.04 [A S A N )/A TG ]

11 Boiler Efficiency Table

12 Poorest U-vales (W/m 2 K) Table 3: Poorest U-values (W/m²K) for parts of elements acceptable as a General rule when using the Target U-value and Carbon Index Methods Element Poorest acceptable U-value Parts 1 of roof 0.35 Parts 1 of exposed wall or floor Whilst parts of these elements may (within the limits given in this table) have poorer U-values than those given in Table 1, it will not normally be practical to make sufficient allowances elsewhere in the design for the whole element to be built to these standards.

13 Carbon Index Approach CI scale 0-10 Compliance = 8.0 or more Relates to Carbon Factor, where CI = log 10 (CF) CF = CO 2 / (TFA )

14 Air tightness All new buildings 10.0 m 3 h -1 m -2 Air-conditioned / low energy 5.0 m 3 h -1 m -2 Superstores 5.0 m 3 h -1 m -2 Archival storage 2.0 m 3 h -1 m -2 Cold / chill stores 0.5 m 3 h -1 m -2 Aircrete 0.12 m 3 h -1 m -2

15 Air infiltration Either adopt robust details Or Pressure test the whole building

16 Robust standard details Buildability Low condensation risk Limited thermal bridging At junctions Around openings Air tightness, not only heat loss from the building but avoiding condensation resulting from cold external air entering the building

17 Other AD L Issues Operating and maintenance Lighting/switching

18 Conflicts between Part L and E Dense vs. Lightweight Robust details

19 Future Amendments Window performance standards Change to the whole house compliance Improving airtightness Control overheating Improving heating efficiency Improving existing stock

20 Celcon solutions

21 Celcon solutions U=0.35 W/m 2 K Full fill Brick Brick Partial fill Brick Brick Clear cavity Brick Brick Solid wall Render Render Render 75mm Dritherm 100mm Celcon Standard Dense plaster 50mm Dritherm 115mm Celcon Solar 9.5mm P bd on dabs 25mm Celotex 100mm Celcon Solar 9.5mm P bd on dabs 29mm Celotex 100mm Celcon Standard Dense plaster clear 100mm Celcon Standard 55mm ThBoard Plus clear 115mm Celcon Solar 50mm ThBoard Plus none 300mm Celcon Solar (TJ) 12.5mm P bd on none 250mm Celcon Solar 40mmThBoard LD none 215mm Celcon Solar 30mm ThBoard Mortar joints: Traditional 10mm except where noted (TJ) thin joint

22 Celcon solutions U=0.35 W/m 2 K Add bullet points here Full fill Brick Brick Partial fill Brick Brick Clear cavity Brick Brick Solid wall Render Render Render 75mm blown fill 100mm Celcon Standard Dense plaster 50mm Dritherm 115mm Celcon Solar 9.5mm P bd on dabs 25mm Celotex 100mm Celcon Solar 9.5mm P bd on dabs 30mm K span TW50 100mm Celcon Solar (TJ) Dense plaster clear 100mm Celcon Standard 55mm ThBoard Plus clear 115mm Celcon Solar 50mm ThBoard Plus (0.33) none 300mm Celcon Solar (TJ) 12.5mm P bd on dabs none 250mm Celcon Solar 40mmThBoard LD none 215mm Celcon Solar 30mm ThBoard Super Mortar joints: Traditional 10mm except where noted (TJ) thin

23 Useful website addresses uk/uvalues/indexwww.

24 Aircrete and Part L regulations So, how does Aircrete help meet the new Approved Document L regulations

25 Background It is approved by the BRE, the BBA and the NHBC

26 Cross section of Aircrete

27 Beneficial properties of Aircrete Lightness Strength Workability Moisture resistance Sustainability

28 Workability of Aircrete

29 Moisture Resistance 100% 100 psi <100% 140 psi 50% 135 psi Standard Brick Celcon Standard Celcon Solar 4 minutes 20 minutes 40 minutes

30 After 30 minutes saturation

31 Drying rates of Masonry Concrete bricks Lwt aggt blocks Dense aggt blocks Cal Sil bricks Aircrete 21 days 35 days 84 days 84 days 84 days Days drying (at 20 C and 44% RH)

32 Sustainability Manufacture Aircrete can be made with the waste product Pulverised Fuel Ash (PFA) Production waste returned to process Low embodied energy compared to other masonry products Handling Lower fuel cost for transport Aircrete is structural and insulating Low wastage