Mass. glazing requirements for school buildings impede energy efficiency
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It appears that Massachusetts now requires low solar heat gain (below 0.4) for windows in school buildings constructed with state aid:
The SGHC must be no higher than 0.4, according to page 186 of this document.
Has anyone attempted to quantify that savings you would gain by planting trees on the south side of the building and using high solar-heat-gain windows instead? Since a school is barely used from june 20 to august 30, it might not even be necessary to run the AC much, giving another reason why high solar heat gain windows could make sense.
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Replies
Rich,
It's unclear to me whether this is an NFRC rating (a whole-window rating) or a center-of-glass rating. In either case, I agree that it restricts designer flexibility.
If anyone else is confused about the page numbering, it's on page 6 of the appendix, or page 184 out of 206 using the page numbers provided by the pdf file.
with a residential building, where the structure is perhaps 25 feet from side to side, I have seen numbers on the order of 15% heating cost savings by taking advantage of solar gain. Do the same numbers apply to a more massive structure, like a high school, where there are a good number of south facing windows but the design is not necessarily optimized for solar gain?