I'm building an off the grid house with double wall construction and I'm concerned about condensation on the sheathing
My plan right now is to use double wall construction and have a catherdral roof. I'm looking for a R-60 on the walls and a R-100 for the roof. A little overkill but when you're off the grid in zone 6 too much is never enough. The wall construction I'm looking to use is from outside to in Betflex siding, 2x4 batten to create an air space, house wrap, 1/2" ply sheathing, 2x4 stud, 2" of spray-on closed cell foam, 15" of dense packed celulose, 2x4 stud, gyps (no vapour barrier). The cathedral roof would be from outside in standing seam metal roof, 2x4 batten, 1/2" ply sheathing, 2" of closed cell spray-on, 27" truss, 27" of dense pack celulose, 1x4 batten, gyps, again no vapour barrier. The idea about the closed cell is that it would create a very airtight house but it means that the vapour barrier component would be on the cold side. Am I asking for trouble with condensation with this set-up and can anyone tell me how to make it better?
Posted May 18, 2014 10:12 AM ET
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