How to insulate the ceiling/roof?
I have a chalet-style house in Virginia which needs insulation. Built about 1970 as a Linden model, it is hard to heat in the winter. We installed a propane fireplace to help the heat pumps in the two stories plus basement. Summers are not such a problem because the surrounding trees give shade.
These houses have no attic. The second story ceiling is about 10′ on a good slope. Exterior walls are tongue in groove and interior walls are cedar. I am replacing all the windows, but the roof is the worst problem. The frame on these types is tied to the roof, so it can not just be changed at will. It can only support modest additional weight.
i had thought of spraying solid core foam 4″ over the existing ceiling. This would add R24 to whatever is there now, maybe R19. That would damage the look but help with the heat loss, I hope.
Does anyone have any experience with such a situation?
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Replies
Robert,
To summarize, you have a cathedral ceiling that you suspect is poorly insulated and perhaps leaky. The ceiling consists of cedar boards. You don't mention whether the roof assembly is vented or unvented.
Your suggested solution is unusual, but it would work. Your only challenge is coming up with a way to attach a new ceiling; that will probably require attaching 2x4s or 2x6s to your ceiling before the foam is sprayed.
Most people who wanted to insulate the interior of a cathedral ceiling would use one or two layers of rigid foam with carefully taped seams rather than spray foam.