Is there a particular caulk, silicone, or sealant that is best to use as an air sealer?
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I’m going to be headed up to my attic soon to air seal any obvious gaps and cracks. This is being done before closed cell foam is sprayed in the rafters. It’s an unvented attic.
What is a good caulk, silicone, and/or sealant to use?
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Most polyurethane caulks/sealants work pretty well on most materials that would be found in an attic, for seams/holes smaller than about 1/2", and would also bond well to closed cell sprayed polyurethane foam.
Closed cell spray polyurethane foam also does a great job. What/where are you looking to seal ahead of time that the closed cell foam wouldn't seal?
Dymonic 100, although there are many others.