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Unvented Attic help

BPortnoy1 | Posted in General Questions on

Hello. My contractors put an unvented attic in my new construction home. We have all air handlers and duct work up there so this made sense. However upon reviewing the code it appears it was done incorrect. I’m trying to determine if I need to rip it all out or is there an easier fix. 

my roof is cedar shingles. Underneath is felt paper. Under that is plywood.  Under that is paper faced r38 Batts with paper faced toward interior. Under that is r-10 rigid foam with a foil face.  The foam board are tightly tapped together.  The foam and foil boards are considered the impermeable layer with attached vapor barrier. See photos of my attic and code. 

according to the code the rigid Boards with foam should have been right against the rafters with the batts closer to the interior. I’m concerned with getting condensation on sheeting and no where for it to dry out. 

on another note during these hot summer days we are having condensation due to the attic being too hot (86 degrees) and the air handlers being 65 degrees. The condensing is dripping down. Not sure if this is related to the improper roof insulation or not. We tried adding a supply only vent from another unit but it isn’t enough to cool the attic  

we are climate zone 4a

thank you!

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