TRR U-value calculator

Transcription

1 TRR U-value calculator User Guide V1.2 January 2011

2 Index 1. Introduction 2. What makes up a whole unit U-value 3. Window/Door styles 4. Window measurements 5. How to access the U-value calculator 6. General overview to the calculator 7. Using default or specific U-Values 8. Panel materials within windows and doors 9. U-Value Calculator Home Page 10. Calculating PVC Window U-values using default values 11. Calculating Timber Window U-values using default values 12. Calculating Metal Window U-values using default values 13. Calculating Window U-values using specfic values 14. Calulating glass units U-values Appendix 1. Window style drawings Appendix 2. Window measurements Appendix 3. Door U-value calculations with side panels Appendix 4. Specific U-Value tables Appendix 5. Timber Mean Thickness Calculation

3 Introduction The Thermal Rating Register U-value calculator is a powerful, yet user friendly, tool for creating whole unit U-values for window and door products. The calculator can be used for a huge range of window designs made with a range of typical materials. The tools are provided to members of the Thermal Rating Register to demonstrate Building Regulation compliance to part L What makes up whole unit U-Values A whole unit U-Value is made up of 3 parts: - The glass unit centre pane U-value - The frame material U-Value - The heat lost from the junction of the perimeter of the glass unit where it meets the frame (known as psi value) Window/Door Styles To accuratly calculate the whole unit U-Value of window and doors the cacluator is split into several window/door styles. Appendix 1 shows a range of styles, choose the style that matches the product to be calculated. Window Measurements The required measurements to calculate the whole unit U-Value are: - The overall unit dimensions - height, width and thickness for timber units - The frame projection size The calculator will work out the proportion of frame area, glass area and length of glazing perimeter Appendix 2 shows the conventions for measurements required in the calculator. How to access the U-Value calculator Each member of the Thermal Rating Register is provided with a unique username and password to the member s area of the TRR website. Access to the member s area is from a link on the TRR industry webpage. After logging into the member s area choose U-Values from the link at the top of the page. General overview to the calculator The TRR U-Value calculator calculates U-Values in accordance with methods & conventions laid down in EN This is an acceptable method for calculating U-Values for part L 2010 of the Building Regulations. The calculator will generate a pdf report of the calculation that can be presented as evidence of Building Regulation compliance for part L. The TRR will audit the member company is able to produce the windows shown in calculations. Under Building regulations door must achieve a U-Value of 1.8, and windows must achieve 1.6

4 Using default or specific U-Values EN has default values for the material types built into the calculator. These will generally always be worst case for any of the material types, actual materials may perform much better than the defaults. However unless actual values are known default values must be used. There are defaults for the following materials: - PVC windows/doors - Metal windows/doors - Timber windows/doors In some cases PVC extruders may provide U-value data for frame materials. In this instance the specific calculator may be used. However default psi values must be used for glazing types.see appendix 4 for value tables for different Spacer bars, PVC systems, and timber. Panel Materials within windows and doors Default values can be used or values obtained from the panel maufacturer. Some panel product values will be provided on the TRR members area.

5 U-Value calculator Home page Log into your members area and choose U-Values from the link at the top of the page. The following screen will be shown. Step 1. Your company name is displayed here Click here to start a new U- Value Calculation A list of your previous calculations will be stored here Step 2. Enter a unique product name or reference number Choose a product type Options door, glass, window Choose a material type Metal, Timber, PVC Choose values Default or specific Choose Style 1, 2a, 2b, 3, 4 Then Click Next

6 Calculating PVC Window U-values using default values Window style 3 Step 3. Enter overall width and height Enter transom and mullion locations using measurement conventions in appendix 2 Choose Click frame Next classification Then click next Step 4. Enter frame dimensions in accordance with appendix 2 Then click next

7 Step 5. Enter centre pane U-Value, calculated from glass calculator Has the unit got a low-e coating Option yes or no Choose spacer option, most popular spacer bar options are included NOTE: For doors choose Layered or single material panel Complete for each window panel and then click next Step 6. The window summary is shown here with the calculated U-Value to 2 decimal places. If the calculation does not meet regulations click back and re-calculate. To review the final product U-Value certificate, click View PDF If the window design matches requirements click Register This Product to save the calculation

8 Step 7. To view the PDF click here To delete an existing calculation click here

9 Calculating Timber Window U-values using default values Window style 1 Step 3. Choose overall dimensions Choose hardwood or softwood, or Idigbo Click next Step 4. Input the projected width of the outer face of the frame in line with conventions laid out in appendix 2 Enter mean thickness of the frame (outside to inside) See Appendix 5, on calculating mean timber thickness Steps 5. onwards same as PVC.

10 Calculating Metal Window U-values using default values Window style 1 Step 3. Enter overall window dimensions Enter frame thermal break Click next Step 4. Enter sizes Then click next Step 5. onwards same as PVC

11 Calculating Window U-values using specfic values Step 3. Same as previous options Step 4. The U-Values and Psi values can be manually entered. The values entered must be obtained from simulation in line with These may be obtainable from your systems company. However, evidence must be provided to TRR for validation on annual audit. Step 5. Onwards same as other options

12 Calulating glass units U-values Step 3. Choose: Double or Triple glazing Click Next Step 4. Choose glass thicknesses for each pane Choose glass make for each pane Choose air space Choose gas fill Step 6. Onwards same as other options. Note: U-Value calculations are not concerned with light transmission, therefore for uncoated low iron glass choose float glass. Where low iron glass is coated such as Pilkington K-OW choose K glass. NOTE: Record the glass U-Value to 1 decimal place for use in whole window calculation.

13 Appendix 1

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15 To calculate a U-Value on the standard window designated within BR443 use window style 2a, if the U-Value is calculated on this style using a size of 1480*1230mm wide, with a centre mullion at 615mm, with the largest face section size or worst thermal performing material

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21 Appendix 2 Measurements for Window U-Value calculations Sizes exclude gasket projection

22 Measurements for Door U-Value calculations Sizes exclude gasket projection

23 Appendix 3 Calculating Door U-Values with Side panels (Certass CPS interpretation) There are many situations where doors will be fitted with a glazed side panel. In general terms these side and / or top panels would be considered a window. However for the purposes of Part L and U-Value calculation they are to be considered as part of the door U-value calculation in the following circumstances: The door and panel must be in a single wall opening, with no piers or alternate material between the door and window The side panel must be full height (intermediate transoms are acceptable) Any top panel must be full width (intermediate mullions are acceptable) The maximum height of any top light must not exceed 600mm, including frame The maximum width of any side light must not exceed 950mm if a single side light or two panels, one to each side, of 450mm For the purposes of sliding patio door, the fixed light is part of the door for thermal calculations, and may include side and or top lights. To calculate the U-Value use one of the following door styles: 2A 3 4

24 Appendix 4. Specific U-Value tables This section includes tables that can be used for different spacer bars, PVC systems and timber thicknesses. Please note the figures contained in this section are considered worse case values, actual values calculated in may vary. Table 1 Ψ (PSI) value defaults of different spacer bars in PVC and Timber Spacer bar HOTMELT Sealant type Polyurethane / polysulphide Aluminium Ulmke Stainless Steel DuraSeal TGI Wave Thermix TX.N TPS Swiss Spacer GED Intercept Swiss Spacer V Triseal Premium Super Spacer Triseal Premium Plus Thermobar Table 2 U-Values for timber dependent on thickness thickness softwood hardwood Idigbo, mahogany, density of 560Kg/m

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29 Table 3 PVC profile U-Values Note figures in this table are worse case and actual U-Values of profile systems/configurations may be much better than listed. System Minimum Steel Full Steel Reinforcement Thermal Insert Reinforcement 3 chamber system chamber system Note: using the above figures will be acceptable for calculation to the TRR scheme and deemed acceptable for U- Value to Building Regulations. However the calculation will not be compliant. System companies included: Aluplast Deceuninck Duraflex Eurocell HL Plastics KBE Kommerling LB Plastics Plastmo Profile 22 Rehau Selecta Spectus Swish Synseal Veka WHS Halo System companies not listed may still meet the requirements above however TRR does not have the required data to confirm acceptance. If you can obtain manufacturers data for a particular system this may be used to override the defaults listed above.

30 Appendix 5. Timber Windows Mean Thickness Calculations H2 Sash H1 TH Mullion T1 T2 Mean Thickness Calculation Mean Thickness = ( T1 *H1) + (T2*H2) TH

31 H1 H2 Sash TH Frame T1 T2 Mean Thickness Calculation Mean Thickness = ( T1 *H1) + (T2*H2) TH Example: If, T1 =80, T2=60, H1=50, H2=40, TH= = (80*50)+(60*40) Then Mean Thickness = How to write the above example as an Excel formula =((80*50)+(60*40))/90 The double brackets are needed for the calculation to deliver the correct figure.