Need some help with insulating cathedral ceiling
I am building a new house and the roof is scissor trusses with a cathedral ceiling. With the trusses I am having trouble figuring out what the best way to insulate is. I am building an unvented attic as described in articles on this site. My system is a standing seam metal roof, sheathing, 3.5″ Closed cell spray foam and I want to add fiberglass under the foam. My problem is with the truss construction I do not have anything to attach the Batts to in order to keep them up next to the foam. I would like to know if anyone has any suggestions for attaching the batts or would I be safe with installing the fiberglass directly above the drywall on the cathedral ceiling?
If I attach the batts above the drywall this will create about a 3′ air gap between the 2 layers of insulation(foam,Batts). Would this work and be safe?
I know the code says ‘directly below’ but does not state intimate contact.
I have asked this question on Fine Home Building but this site seems to get more traffic with a lot of experienced people.
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