Bonus room ceiling and kneewall insulation
New construction zone 4 on the line with zone 5 (47460)
Bonus room over garage with radiant floor heat in garage floor
2×12 bottom cord in the floor and 2×8 rafters.
I plan to pre-hang drywall on the knee wall in the bonus room and spray 3.5 inches of open cell foam in between those studs. Then I plan to install 1.5 inch fiberglass faced PolyIso rigid foam on the attic side of the knee wall and tape the seams.
In the ceiling I plan to install the polyiso foam on top of the raft bottom cord (in the small atitic ceiling) then spray the open cell foam against that rigid foam from below.
What to do about the area between the upper attic and the lower attic? This is a vented attic space so accuvent baffles are what I plan to use continuously from soffit to ridge vent.
2″ closed cell against accuvent tunnels for venting?
unfaced ruxol against the accuvent tennels?
Please help me understand the best options.
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