I am replacing the Hurd Mirror 88 glass units due to fogging between the panes. The windows guy first suggested Oldcastle Glass - PPG Sungate 500 on Clear Low-E #2, with Argon fill. Visible light Trans =74%, UV Trans=42%, U=.31 and SHGC=.62, Solar Trans=52%. When I complained about the amount of UV (our Hurd is only .5% UV transmission), he suggested the following:
Pilkington Energy Advantage Low-E #2 with Argon fill, visible light transmission, 69%, UV Trans. 28%, U=.28, SHGC=.59, Solar trans=39%. Is the UV low enough to protect furnishings? Are the other changes okay? What I want is to gain as much heat in winter and as much visible light as I can without overheating in summer. We have 2 foot overhangs (passive solar with concrete/tile floors with lots of south facing windows) and trees around the house to help in the summer.