Add insulation to this cathedral ceiling?
We recently purchased a log home with a built up, vented cathedral ceiling. From the plans (left behind by original owner) and what I can tell from poking around the assembly from the inside is… open rafters – tongue and grove pine ceiling – 4 inches foil face rigid foam (foil towards TG pine) — 1 inch airspace via prefabbed baffle — plywood, felt, shingles. In our up stairs bedrooms there is additional TG pine on the bottom of the rafters (presumably to match the TG pine on the dormers where they are no exposed beams). See attached sketch. My question: I have some of the first layer of TG pine pulled off in a bedroom for another project and it occurred to me that there is a nice cavity (~91/4inch deep) there where i might could add batt insulation. Would it be advisable to add insulation here and if so would unfaced batts be a good choice?
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