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Community and Q&A

Air sealing for casement windows

user-721843 | Posted in Energy Efficiency and Durability on

My 1950’s apartment has a large window. They are about 10 feet long and 4 feet high. There is a fixed center panel and a casement on either end. Single pane, metal frame. The frames are a bit wracked out of square, probably from earthquakes over the years, and won’t close fully. (coastal southern california mild climate but winter nights are in the 40’s with a medium Santa Ana wind ).

basically there’s a variable gap on the casements, anywhere from 1/4″ to almost 1″. Can anyone recommend a decent draft-stopping product/technique? I’d like to also be able to open the windows for those random February 75 degree days, but can live without that. I tried the rolled peel and stick weather stripping, but sizing becomes an issue and the material seems to get beat up by the sun, wind, and dust and wont stay long…

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  1. GBA Editor
    Martin Holladay | | #1

    I don't know whether you own or rent your apartment. It certainly sounds like you need new windows.

    If your casement window has a crack that is almost 1 inch wide when closed, then weatherstripping won't help. It sounds like your window frames are made of steel or aluminum. Assuming that you have permission to work on the windows without angering your landlord, you might be able to drill a 1/4-inch hole in the casement frame. Drill the hole in a location that lines up with the metal frame, near the part of the window with the widest crack. Then insert a long 1/4-inch bolt, a flat washer, and a wing nut. Tighten the nut to keep the window closed.

    Of course, this would be dangerous if the window is a necessary egress window for use during a fire emergency.

  2. user-721843 | | #2

    Thanks Martin. I rent and I'm sure the place could use new windows, but there's not much incentive for the landlord to take on that huge cost - nevermind what else they might find when they get into that work. It's a 3-story, open square, 35-unit apartment building.

    Your drill idea may work though. It's not intended as an egress window ( though I have sized up the outside palm tree, just in case). I suspect that if I can pull the window back fully closed, it will stay via friction fit and not need to be bolted. Otherwise, I can probably get creative with being able to somehow stuff the gap. I'm lucky energy bills are really low here - this is more about thermal comfort.

  3. gusfhb | | #3

    how about a piece of that soft gray foam they sell for window air conditioners, and a swath of Gorilla tape. 'wicked' sticky and doesn't quite look like duct tape, which it really is

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