Insulated impact-resistant windows
I have a house in Florida (climate zone 2a) with windows facing west. We replaced all windows and sliding doors with white aluminum frame impact rated, insulated, low e glass with grey tint. The specifics on the windows are: Insulated, large missile, Low-E = Windoor GR2, grey tint, 3/4″
NFRC ratings: U factor =0.61, CR = 16, SHGC = 0.23, VT = 0.29
We have a serious problem with heat gain in the afternoon now. On a recent day where the outside air temperature was 81 degrees, the outside temp of the glass was 123 degrees and the inside glass temperature was 112.4 degrees. It is like turning on an oven in the house which is not what I expected after paying a lot of money for these windows. I thought the insulated, impact and low SHGC rating would help keep heat out, not amplify it! I have tried calling window companies but cannot get an answer as to how much heat should reasonably come through.
Is this normal? Are there alternate products or window that don’t transfer heat this much?
I can provide the spec sheets if needed.
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