Confused about "g" value of windows and the WEP database

fclauson · 2010-12-01 07:33:00

Can someone help me here the WEP database as http://www.nsai.ie/Our-Services/Certification/Agrement-Certification/WEP-(Wind-Energy-Performance)-Scheme.aspx has windows which are highly energy efficient with a "g" value of 0.30 to 0.40 DEAP uses 0.63 thus to get a high performance window you seem to have to give up solar…

01-12-2010 08:33AM

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fclauson

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Can someone help me here

the WEP database as http://www.nsai.ie/Our-Services/Certification/Agrement-Certification/WEP-(Wind-Energy-Performance)-Scheme.aspx has windows which are highly energy efficient with a "g" value of 0.30 to 0.40

DEAP uses 0.63

thus to get a high performance window you seem to have to give up solar gain

Am I miss understanding this

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#2 01-12-2010 08:58PM

sinnerboy

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g value 0.63 relates to the glass only .WEP values are whole window

DEAP also asks for a frame factor - defaulted to 0.7 , meaning the glass area is 70% of the whole window area.

So 0.63 x 0.7 = 0.441 , is more like the whole window g value you see on the WEP certs .

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