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I live in Coastal California, mild climate. My cathedral ceiling is uninsulated. I want to insulate it. I put a new roof on 6 years ago, so now want to insulate it from the inside. Don’t want to vent it. The roof is composition shingles, paper, 2xT&G, thats it. From inside I can see the T&G.
My idea is to put rigid insulation board (polyisocyanurate) firmly against T&G on the inside, then fiberglass, and sheet rock over that. Opinions?
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Replies
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You can get a product called therma liner that is Expanded Poly Styrene foam bonded to drywall. It is available in different thicknesses to acheive the R-Value you require. Try and stay away from the Poly Iso as it is pretty nasty stuff and off gasses Freon which is the very thing that gives it its insulation value and as a result it loses value over time.
It is a shame to lose the T&G look and if you really want to do it right add NailBase insulation to the exterior and sacrifice your 6 year old roofing. More expensive but a better result will be achieved.
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I live in Coastal California, mild climate. My cathedral ceiling is uninsulated. I want to insulate it. I put a new roof on 6 years ago, so now want to insulate it from the inside. Don't want to vent it. The roof is composition shingles, paper, 2xT&G, thats it. From inside I can see the T&G. My idea is to put rigid insulation board (polyisocyanurate) firmly against T&G on the inside, then fiberglass, and sheet rock over that. Opinions?