Cathedral meeting attic insulation
I’m insulating my new construction home and I have a cathedral that meets an unconditioned attic.
I was wondering what kind of R-value should I be trying to get in that area?
The cathedral is R-30 of rock wool, and is sheathed with 2 inches of rigid foam, and cellulose in the attic.
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Replies
User-7220186,
First of all, can you tell us your name? (I'm Martin.)
Between your unconditioned attic and the high-ceilinged room with the cathedral ceiling, I assume you have a wall. That wall needs to be insulated just like any exterior wall.
I'm devin I'm building in central pa yes I have a wall between the two was wondering if r21 Batts would be sufficient or if I should sheet with Ridgid foam as well
I'm currently building a similar intersection and have put an extra 2" rigid foam on the "cold" side of the sheathing that would be in the unconditioned attic. Maybe it's overkill but I figured a little extra there would be beneficial as an attic can get pretty hot in the summer and cold in winter.