Improvement of older windows…
My son’s home has a “great room” with lots of window area, including two double doors to a deck (one fixed glass panel and one door), rectangular windows above each door of nearly equal size (same width, slightly shorter), and two triangular windows at apex of ceiling/roof. These are 20+ year old standard thermopane wood windows of the time (seals appear to be intact).
Obviously, replacing these windows with newer, energy efficient windows would be best, but simply not a financial possibility right now. My question is, does anyone have practical advice about how to improve these for now and at least several years hence?
We have used some of the thin plastic film on lower windows (the kind installed with two sided tape and tightened with a hair dryer) on lower/smaller windows. This is effective, but we were looking for something better. That film needs annual off and on, and on the larger windows, with only exterior framing for taping the plastic, the stuff sags easily and looks rippled.
Does anyone have experience with storm panels,-either plexiglass type product or glass? Should such a panel, if feasible, be inside or out? Is it possible to prevent moisture from getting in between and clouding things in the winter? Are there quilted type interior “curtains” that seal and can be easily opened day/night for up high windows? Ideally, an interior or exterior panel that can be left in place would help, but not sure if this can work.
Thanks for any and all advice.
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Replies
Howard,
Contact a storm window fabricator. There is no reason that you can't install exterior storm panels on the windows. The door may need to stay the way it is, although it always makes sense to double-check the integrity of the door's weatherstripping.
When ordering storm windows, it's well worth considering low-e glass. The upcharge for low-e is well worth it if you live in a cold climate.
The higher cost of low-E glazing is worth it in cooling dominated climates as well. Hard coat low-E (indium tin-oxide) isn't as good at heat rejection as softer specialty low-E coatings, but it does at least some.
Larson storm windows are available through the two mega-chain box stores in most US locations. It's worth upgrading to their "silver" or "gold" series (particularly on the operable windows) for better air tightness, nicer hardware, etc. In the northeastern US Harvey Tru-Channel would be another option. IIRC Larson also sells interior storm panels, but you get better air seal and overall performance with an exterior approach using a better-grade tighter storm window.
A low-E storm window over a U0.6 1970s vintage thermo-pane will perform at about U0.26-0.28.
I've done some internet research regarding storm windows, per above advices, and I see there are some good options I was unaware of. There is a company called Innerwindow claiming interior storms are far better in general, apparently because exterior ones need "weep holes" and inners don't? Does this sound correct? I think either could work in our case, but would lean toward inner if they were so much more efficient as claimed.