Caulking studs in spray foamed wall
quantumgirl
| Posted in Energy Efficiency and Durability on
I have a question about air sealing. I taped the seams in my exterior sheathing with Siga tape. Stud bays are insulated with open cell spray foam. Do I still need to caulk in between double studs, double top plates, bottom plate to subfloor, electrical outlets to Sheetrock etc. or would that be redundant and a waste of time and money?
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Replies
You still need to caulk between any sistered framing members (doubled studs, etc.), because the spray foam can't get in there to seal that space. The taped exterior sheathing helps, but I'd still caulk the sistered things to be safe, and I'd included bottom plates and top plates in that.
I wouldn't worry as much about the electrical boxes since the spray foam should seal better, but since open cell spray foam can take on some moisture, it wouldn't hurt to put at least some level of sealing effort into the electrical boxes. I would put sealant around the top plate to seal the drywall though, to prevent leaks up to the next level or attic space.
Bill