hello all i have a house full of replacment windows and would like to know if there is a way to insulate the window sash wieght cavity without removing the trim
noah
From building boxes and fitting face frames to installing doors and drawers, these techniques could be used for lots of cabinet projects.
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Replies
You can drill a series of holes at different levels into the weight voids and spray Great Stuff or similar into the void. Exspensive ( 1 can per window), and be careful not to spray in too much so that the cavity gets distorted by the foam pressure.
Tough to do effectively without removing the trim. If you do ever remove the trim, use a length of PVC for the weight to ride in, and insulate all around the pipe. Minimally expanding foam (for doors and windows) works great for this.
Window installer tells me they won't use foam because when it hardens and the wood expands/contracts, air gaps open up. They prefer to stick in FG (or I could use foam insulation). I doubt this is such a big deal, though I've heard an advantage of open cell over closed cell foam is the former moves with the wood.BTW I wouldn't spray foam out of a can into a window, I'd use a foam gun to give tight control over the amount of foam.
Taylor, it's been my experience that spray foam insulation allows a lot of air infiltration. I had a picture window that was feeling quite cold until I replaced the foam with fiberglass.
blue
Blue, this is hard to understand, as my understanding of the 'extensive' FG vs cellulose debates made it clear that FG would NOT stop air infiltration. In this application, I'd think FG would work fine AFTER the infiltration is stopped with caulk, foam, etc.Thon
I have cotton insulation (made from denim with PDBEs) which would work better than FG. My only concern is condensation in the absence of a vapor barrier.I'd worry with a can of Great Stuff, but with a foam gun you can get a good handle on controlling amount of foam.Interested in your experience though....
Just curious, but wouldn't it have been easier to insulate the pockets while installing the windows?
Anyways, I prefer fiberglass. It's easier to control, and just as effective.
Stacy's mom has got it going on.
Blue's right. Even though I've used it many times on windows, I have sworn off spray foam or expanding foam around windows. There's too many problems, especially with the expansion along with the movement of the wood. I do everthing in fiberglass anymore, new and old.
Once you take the stops off there's a screw on the inside of the jamb. Unscrew that and the piece of jamb comes out. Once you cut the chains from the window sashes and take the sashes out you will see the weights fall down and you can take the weights out and then stuff the cavity with insulation. You don't have to take the casing off.