Closed-cell foam / Flash and batt
I am in the process of reinsulating my home. I have a 1,000 sq. ft. flat roof. Under the roof is 6″ wide tongue and groove boards attached to a 2 x 6. It’s sloped ( -2/12 pitch).
I would like to use a “flash and batt” approach. I’m a little unclear on venting. Does it need venting? Currently I have 2 sides vents and a soffit off the back of the house.
Would 1″ to 2’of closed cell foam with R-38 batts be ok? Or would foam board be better? Under the roof is more then enough space to accomodate the insulation. I like the foam idea becuase the house is in the woods. Just concerned with moisture, bridging, etc.
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