Spray foam & sealing off soffits from attic
I had a spray foam contractor to my house last week to discuss spray foaming the underside of our roof deck. We did everything in renovating our home right except for the ~30 can lights we had put in. I don’t notice heat loss as much but the heat gain in the summer is obvious. I’ve given up trying to insulate and air seal so I want to move the envelope up. I’ve researched this a bit and know that the recommended approach to seal off the soffit from the attic is to insert a square of rigid foam and spray foam over it. That will be a pain in our house because our roof has a shallow pitch. Just getting to the soffits requires some dexterity. Doing this several hundred times at each opening would be very labor intensive.
The contractor said they solve this problem by shoving a piece of batt insulation into this crevice and then spray foam over it. The batt insulation works as a backstop for the sprayfoam. I wasn’t sold on this approach as it seems like a shoddy short cut. At the same time, it didn’t seem crazy and certainly sounds easier. Any thoughts?
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