Tooger Smith
Building a new house this summer. We have a vaulted ceiling with 2 by 12 rafters, 16 in. O.C., purlins 24 in O.C., radiant barrier (bubble wrap?), then screwed down metal. The question is now what is best in order to insulate properly. 5/8 drywall will be inside. How about 2-3 inches of closed foam spray, then mineral wool batts. Then put the drywall up without a vapor barrier on the inside. Am I thinking right about this. Thank you.
Todd Miller
Isaiah Industries, Inc.
I think that sounds reasonable. However, if you're not going to have any vented space behind the ceilings, I am not sure I'd see a problem with adding a vapor barrier behind the ceiling, just in case.
Eric Novotny
An informed customer is the Best Customer!
+1 Well thought out. Just make sure they do the foam in 1" lifts at the max.
Tooger Smith
Thanks. Another option I found today would be to use 3 in polyiso panels and cut them to fit between the rafters, rather than the mineral wool batts. More labor, but I can get them for a very good price. Worth the effort? Thanks again.

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