Insulating behind window trim vs sealing around window trim
I went and sealed around the edges of my window trim a while back, after thermal imaging demonstrated leaking & we had already hit all the other big leaks. I did the side casing to wall, and side jamb to window casing.
I’ve noticed a few cracks I missed (side casing to side jamb) that have dust accumulation, clues showing where air is actively (not just theoretically) leaking out of the building.
But since I did the sealing, I learned that I probably was “supposed” to pull the trim and seal the gap between the window & frame, instead.
At this point, should I go ahead and seal the side casing to side jamb with caulk? Should I strip all the caulk I already laid and seal behind the trim instead? Does the insulating value of expanding foam provide any meaningful benefit? I am generally very attracted to “correctness”, and I like the sharp clean edges of the uncaulked wood trim, but it seems I’m likely to do some damage trying to strip the old caulk.
I’m definitely committing to sealing it as best I can one way or another- as discussed elsewhere, I put in a humidifier for medical reasons, so continuing air sealing remains very important work even though we’ve already got the envelope “pretty tight”. Thanks.
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