Is insulation required for an unvented exterior 12’x25′ portico roof in climate zone 7B?
New barn construction is using an unvented roof (metal shingles over underlayment and 5/8″ plywood) with closed cell spay foam in the interior cathedral ceiling.
The exterior portico entrances and shed roof over a deck are also unvented and will have 1×4 T&G cedar covering the rafter bottoms.
Is insulation required in the exterior areas? If yes, what would be recommended?
Thank you, Ed
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