Vaulted ceiling insulation with skip sheathing
This is how I plan on insulating my upstairs bedroom. I’m vaulting the ceiling and leaving the collar ties exposed. I put furring strips to maintain a 1 1/2” vent space. I’m putting two 2” layers of R-Max polyiso in the rafter bays and one 2” layer over the rafters to achieve R-39. I will spray foam the 1/4” spaces in between the foam board and rafters/collar ties and tape the seams on the final layer that’ll cover the rafters. Thoughts?
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