Air sealing electrical box knockouts - spray foam or something else?
In a room I'm renovating, I'm getting ready to install insulation batts. But before I do, I need to air seal the electrical box knockouts (where the wires enter and exit the outlet boxes).
I was going to use canned spray foam for this. Any tips on minimizing how much foam enters the box? Maybe stuff a rag into the box and press it up against the knockouts while I foam the outside of the knockouts?