Insulation options for cathedral ceiling.
taylore2003
| Posted in General Questions on
For an unvented hip roof over a cathedral ceiling / living space, do I have any options beyond closed cell spray foam?
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Replies
Can you furr things out enough inside to get to code minimum R value plus at least 1" of vent space below the roof deck? If you can, then you can still build this as an insulated assembly, but with a lot more labor than it would take to do it with closed cell spray foam. If you can't build it vented like that, then your only option is closed cell spray foam if you want to be safe.
Bill
taylor,
Yes. This article lays out a few un-vented assemblies we know work:
https://www.greenbuildingadvisor.com/article/five-cathedral-ceilings-that-work