For all those Replacement Window questions
9 posts • Page 1 of 1
Just curious - how much impact to performance does GRG (grids between glass) make in a window compared to no grids? I suspect it's negligible but would like to confirm. I'm asking as window ratings are typically based on units without grids as that is the optimal performance setup. But, since my home currently has grids, I'll probably run them top & bottom in the replacements to keep the architectural style intact (leaning toward Okna).
- Delaware Mike
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- Location: Delaware, New Jersey, Philadephia Area
I've never seen it change the overall u-factor in reference to the NFRC sticker on a window verses a non-grid window. OKNA seems to do a really nice job with their grids in terms of quality control as that's an area in which all manufacturers encounter some small percentage of misalignment during the manufacturing process of the glass.
- Window4U (IL)
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On pretty much all the brands I've carried it's been a .01 difference. An example would be a .26 with GBG grids, a .25 without GBG grids.
- Windows on Washington
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I have seen a 0.01 delta one time. Can't remember which window, but that would be the largest offset and it is basically negligible.
Good catch Paul. The double pane is is the same with and without, but the triple pane does change by a point according to the nfrc. Probably not an incredibly common combo, but it's there none the less.masterext wrote:Eric
I seem to recall the 500 series in triple pane going from a .19 to a .20 with grids.