Why caulk between studs, etc?
I understand that a small amount of air can pass through the gap between two or more side-by-side framing members, but so what? Then that air hits the drywall, which is an air barrier. In the middle of a stud bay, that same air is passing through fiberglass batt insulation (not an air barrier) and hitting the drywall. What’s the difference? For that matter, why caulk the drywall to the top plate? Isn’t the intersection of the wall and ceiling drywall taped and mudded? Isn’t that an air barrier? Further, I always caulk that intersection after primer, but in the past that’s been to prevent hairline cracks in the plaster or gypsum from showing. I can understand sealing between the bottom plate and the subfloor. Someone please help me understand this! I’m sure I’m an idiot but would like someone to prove it.
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