Insulating a cathedral ceiling
I have a cathedral ceiling that in the winter bleeds. The bleeding is brown in color, which I suspect is residue from the paper face of the insulation caused by the lack of air flow from the eves to the ridge.
The roof system is made up of 2×8 rafters, 3/4 OSB roof sheeting, and asphalt shingles. the interior ceiling is “Ply Bead” a decorative sheet of 3/8 plywood with a routered bead board design in it. The rafter cavity is filled with 2 layers of R-13 rolled fiber glass insulation with a 1/2 space between it and the underside of the roof decking .
I am about to replace the roof so now is the time to address the insulation.
I can not remove the ply bead so I have to insulate from the outside in.
Can I use spray foam in this application? Can I use a combination of ridge foam panels between the rafters and fiberglass? or ridge foam panels between the rafter alone?
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