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Insulating and Air-Sealing Around Windows

jamesboris | Posted in Green Building Techniques on

New build in Zone 2A w/flanged windows. When I’ve installed windows before, I used canned foam on the interior gap (between the opening and the window). This time, I want to try something that I think will be better: Rockwool in the cavity + Air Dam or tape to seal it. 2 questions:

1) I’ve used canned foam before, but with that, you must avoid filling the entire cavity (which creates a moisture trap). Would it be okay to jam-pack the entire cavity with Rockwool, long as I leave space for backer rod + Air Dam? I’ve never used it before.

2) Anyone with experience or tips on using “zero reveal” air sealing tapes like Tescon Profil, or Solido IQ-D? I like the idea, but I wonder how well stuff like these “bunny ears” work in the field… Also, I’m having trouble thinking of a way to do this with windows that will get a stool and apron.

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  1. Andrew_C | | #1

    WRT 1), mineral wool is air permeable and doesn't swell, so filling the cavity up to the backer rod should be okay. I doubt that you need to "jam-pack" the cavity with mineral wool like we used to with fiberglass. Just filled with a good friction fit should be fine.

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