Attic conversion to living space
We are getting mixed advice on how to properly insulate an attic roof which will become a living space. The peak of the room will be 7′ and with a 6.5 – 7/12 pitch terminating at the exterior bearing walls. There is a 3′ pony wall on both sides which makes the shorter dimension 14′, the long (ridge direction) is 30′ (trying to help you visualize here). Behind the pony walls are “dead spaces” with blown in insulation between the floor joists, which continue another 5 or 6′ to the ext bearing wall (the ones mentioned before). The rafters are 2x6s at 24″ oc and will remain.
Thank you for reading this far… The question is how to insulate the ceiling/roof and with what? I found your article (Martin) about closed vs open cell foam, and venting vs unvented roofs but am having a hard decision because of the shallowness of the rafters. And should the roof be insulated in the dead space to the bearing wall? Does there need to be an air gap all the way to the eave since that dead space between isn’t conditioned? I’d love to get away with using Batts for the ease of installation and repair.
Finally, we wanted to finish the ceiling with gyp board and I’m curious how to make it airtight to help reduce any potential moisture build up. Thank you for any advice. -B
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