when the frame effects are captured within the energy modeling software option the output results for vertical glazing assembly U value will vary based on window size. due to the frame effect.So which value we should enter in the Table 1.4.2B- Fenestration ? or we can enter center of glass U value ? instead of Assembly U value & put additional note that we have used separate frame & glazing inputs in energy simulation with frame details.
You rely on LEEDuser. Can we rely on you?
LEEDuser is supported by our premium members, not by advertisers.
Go premium for
Marcus Sheffer
LEED Fellow7group / Energy Opportunities
LEEDuser Expert
5909 thumbs up
May 24, 2017 - 2:32 pm
I would enter the weighted average U-value of all the windows. This is what the reviewer wants to see.
I frequently see the glass and frames separated in the modeling software but the end result is not accurate.
Jean Marais
b.i.g. Bechtold DesignBuilder Expert832 thumbs up
May 24, 2017 - 2:45 pm
If your software does not calculate the assembly (frame + glazing) resulting rated u-value according to NFRC (ISO 15099), then use another software like WINDOW from LBNL. This will show you the "rated" assembly u-value. If you are trying to input the parameters into the program, do so, so that the assembly "rated" u-value is correct. A good trick for energyplus, is to use WINDOW to help generate the idf code required. This is typical for the baseline. It's a bit itterative changing glazing and framing parameters until the calculated assembly rated u-value is what you require it to be. Good luck.