How should I insulate a small shed/studio with a single-pitch shed roof?
I live in the maritime PNW (rainy Western Washington lowlands) and plan to insulate a recently-built backyard studio/”fancy shed” ala the recent tiny house craze. 8′ x 14′ building with long shed roof about 15 feet long. Metal roof over plywood and 2×6 rafters. I would like to install a tongue and groove ceiling. In this environment, I’ll probably be running a dehumidifier part of the time.
Should I vent each rafter bay (round soffit at bottom and top blocking) and do cut-and-cobble rigid styrofoam insulation sealed with spray foam? Then a 6-mil. vapor barrier and my T&G?
Or should I not vent each rafter bay at all and use batt insulation and call it good?
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