Low-E storm windows for Northeast?
I am replacing storm windows on a 1920 Bungalow with single-pane, wood windows. My question is whether to use Low-E storms, or go with clear.
The house doesn’t get much light, and I’m concerned it will make everything much darker, while not really adding much in terms of keeping the heat in.
I’m not worried about cooling – the house is well shaded with large over-hangs. I’m most concerned with keeping the house bright and warm in the winter. The existing walls are un-insulated concrete block (cringe.) The heating system is a FHA furnace with a pellet-stove in the main living area.
Any advice on Low-E coatings in the northeast & how much they actually help with heating, and how much light they prevent would be greatly appreciated!
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Just want to add a question: would it make sense to do the low-e storms on north, east and west elevations, and then do clear glass on the south?
I'm trying to maximize solar gain and light levels - with the overall goal to keep house as warm and bright as possible in winter. It'll never get too hot in summer - house is well shaded with large overhangs.
Not all Low-E coatings will make things noticeably darker. About the best balance between keeping things bright and maximizing thermal performance is loE-180. I use that for my own northern windows. If you are using double pane windows, i89 helps too with only a minimal reduction in visual transmission (VT) of a few percent. If you are using triple pane windows i89 is of less overall benefit.
A lot of window manufacturers are pushing loE-340, the most aggressive common coating, for tax incentive reasons. This coating takes a bigger hit in terms of reduced VT for a small gain in thermal performance over loE-180 and isn’t really helpful in north-facing windows since the biggest benefit to loE-340 is reduced solar gain.
Bill