Stopping installed window cold air leaks?
steelwindmachine
| Posted in General Questions on
The previous owner of my home replaced and added more windows. Unfortunately, many of them were not properly air sealed at the rough opening and, if I had to guess, maybe not well on the exterior sheathing side either. I’m not experiencing any signs of water intrusion or mold on the interior that I can see.
The windows are nearly all American Craftsman vinyl framed, LowE glass and installed into 6″ deep walls (2 x 6 studs). There are three Anderson proper windows and an Anderson sliding glass door.
It’s been very cold here in NJ and this amounts to many noticeable streams of cold air that emanate from around the interior window decorative trim that is installed around the drywall window opening on the inside wall.
There are unsealed gaps between the inside vinyl window frame and the wooden side jamb where the cold air also shoots through.
On the one hand, I’d love to figure out a way to get to the RO and pack in Rockwool bat and then seal over with Tescon Vana tape. However, I expect that’s going to require me to rip apart the drywall.
On the other hand, I’m thinking the easier, but still effective for air infiltration stoppage would be to seal the gaps between the vinyl window frames and the inside jambs along with sealing the wall trim to both the side jambs and the drywall with a bead of Dynaflex 230. I realize this doesn’t stop the cold air infiltration into the walls themselves and the associated cold/moisture sinking of the wall, but for an immediate comfort improvement, this seems the least expensive and deconstructive.
Any thoughts?
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Replies
It's likely you can carefully pry the trim off, seal the window to the RO, and the put the trim back up without needing to rip apart the drywall.
The trim is attached to drywall. Pulling off trim will just expose the drywall that runs to the edge of the inside jamb.
I believe the RO is in the wall, under the drywall =\
Hi Steelwindmachine (be great to have a name for you in the GBA community) -
The trouble with caulking or sealing around all the trim is that over time, everything moves and all of your hard work will be for naught.
Tapes on the other hand are flexible and especially when mechanically supported by the re-installed trim achieve a long-term seal.
If when you remove the trim you can't get into the rough opening enough because the gypsum wall board covers, just cut out the GwB to fully expose the un-insulated/airsealed gap between the window unit and the rough opening.
Word of caution however: In my own home, I did sash replacement in my 100+year old window frames. I did remove all the trim and insulate and airseal the very space we are talking about. Imagine my disappointment when I STILL felt cold air coming through both the sash overlap of the double-hungs and right through the sash replacement vinyl side jambs.
Lousy windows can overcome the best of your work, in my experience....
Peter