Suggested insulation for area between ceiling and flat roof?
I am replacing the sheetrock in my home and also the insulation. The house originally had a flat roof (gabled roof was added later) so the insulation will go between the sheetrock and the flat roof. Several questions related to this: 1) What recommendations for the type of insulation to use? I'm thinking for the walls I will be using cotton insulation but is that the best option for the ceiling as well? 2) What is the best method to hold the insulation in place before the sheetrock covers it? Thanks!
While I know plenty of people that recommend / install fiberglass or cellulose I would actually lean towards to spraying closed cell foam directly against the sheathing - at least 3" in your area & then top it off with dense packed cellulose, cotton, or maybe even open cell foam depending on the depth of opening. (they use a net like structure or binders for the first two) Before you do any of this though, I would have the roof (and sheathing) fully checked and any needed repairs made. Also, make sure all your bath & kitchen vents actually vent outside & any duct work in that area is sealed up well / they can actually spray above it. While this may cost a little more to install, the results are well worth it