Insulating between studs with polyiso scrap?
Wasn’t sure what category to put this in, but my situation is that I had most of the exterior of my house covered with foil-faced polyiso insulation (Rmax Thermasheath-3). The walls between the living space (bathroom, laundry, pantry, hallway) and garage did not get this treatment, but they still need insulation. I ended up with some scrap due to normal wastage, as well as some extra sheets (since we had to buy some of it by the pallet). My plan has been to cut it to fit in the stud bays and foam around to hold it in place/air-seal. With the smaller scraps, I was thinking of just piecing it together like a jigsaw and foaming it together.
The work area is relatively small and I’ve got time on my hands, but before I went down this path, I wanted to check with the community if this would be a good idea, if there were some things to watch out for, or any other information people might have. None of this will be exposed, it will all have sheetrock and/or OSB on one side or the other.
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