Metal Roof for Vaulted Ceiling

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.		Tooger Smith 3/27/2015	Share Or copy this URL: https://www.metalroofing.com/spirit/comment/20250/find/
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.		Todd Miller Isaiah Industries, Inc. 3/28/2015	Share Or copy this URL: https://www.metalroofing.com/spirit/comment/20251/find/
+1 Well thought out. Just make sure they do the foam in 1" lifts at the max.		Eric Novotny An informed customer is the Best Customer! 3/28/2015	Share Or copy this URL: https://www.metalroofing.com/spirit/comment/20252/find/
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.		Tooger Smith 3/31/2015	Share Or copy this URL: https://www.metalroofing.com/spirit/comment/20253/find/

If you would like to reply to this thread, please log in. If you do not have an Ask the Experts forum user account, create one here.