Sealing gaps between rafters and rigid foam
I’m cutting and cobbling in Rigid foam panels in my rafter bays to insulate and create 1 inch air gaps to ventilate. Most of the gaps between the edge of the foam and the rafters are between 1/4 inch and 3/4 inches and I plan to use great stuff to seal these gaps.
There are stretches where the foam is right up against the rafter or less than 1/4 inch away, and I’m wondering how to deal these smaller gaps. Is there a specific caulk anyone would recommend? Any other technique?
Also, I’d appreciate anyone’s advice on sealing these gaps in general. I’m doing my best to clean out the dust where the seal will be with a stiff bristle broom. I’ve heard it helps to wet the surfaces a little too.
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