Barrier on inside of mineral wool batts in Zone 6?
I’m converting a garage into a family room, and I have it down to the studs right now and am getting ready to insulate. I’ve furred out the studs to make a 2×6 wall, and on the outside I have LP Smartside siding – tyvek – 3/4″ board cladding.
I’m technically in Zone 6, but I’m close enough to the coast that it’s really Zone 5 ish.
I like the idea of mineral wool batts, but I’m finding a lot of contradictory information about whether or not I should have a barrier on the interior of the installed batts. Membrain? Poly Sheet? Just put up drywall and call it good? Everyone local I’ve talked to tells me to just put up faced fiberglass and forget about ‘all that new stuff’.
The rest of the house is 2×4 construction with ~50 year old fiberglass batting, so this is going to be the best insulated room in the house no matter what I do, but I still want to do the best I can in terms of efficiency/longevity.
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