Vented roof insulation
DexterBob
| Posted in Green Building Techniques on
For a vacation home in a 5b zone, does it make sense to put exterior rigid insulation (1″ xps) under a standing seam metal roof? This will have a vented attic with no mechanicals up there. I anticipate blow-in on the ceiling deck.
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Replies
Robert,
You have to choose where you want your thermal barrier to be. You can either establish your thermal barrier (your insulation line) on the floor of the attic, or you can make it follow the line of the roof. But you have to choose.
If you are installing insulation on your attic floor, and your attic is vented, there is no reason to put any insulation above the roof sheathing.