Low slope roof and what type of insulation?
I live in Seattle – Marine climate – in a single story home built in 1962. I have a low-slope roof (2/12). The “roof rafters” are 4 x 8 beams at 48″ o.c.. The roof decking is 2×6 T&G planks. The entire ceiling is vaulted. In other words, what I see from the inside are the 4 x 8 beams and T&G decking. That’s it!
Right now, there is a layer of built up roofing with a mod-bit cover. I’d like to add as much insulation on top of the deck that I can afford and re-roof with TPO or white granular coated mod-bit.
Concerned that if I add that insulation , I’ll now be trapping interior moisture traveling through the T&G planks and cause problems.
How would you add insulation to the roof? Adding from the inside is not an option.
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