Hot roof… potential moisture issues…
In the process of building new home. 2×6 Gambrel roof. This is an Amish built loft barn… converting to house. From the outside in… my roof assembly is structural asphalt shingles, synthetic roof underlayment, 1/2 OSB, then 2×6
roof truss. Inside the roof cavity I have about 4 inches of professionally installed closed cell spray foam, followed by R-13 faced fiberglass batts. Facing is towards the heated space. Lastly I have 5/8 mold resistant drywall on the ceiling.
I’m concerned that the fiberglass batt facing may cause me a trapped moisture issue within the fiberglass. There is no air flow or ventilation in this roof anywhere… soffits and ridge vent are completely closed off. Of course the fiberglass batts are “compacted”.. into the 2 inch space in the rafter cavity. The batts were installed for soundproofing, some R value, and for the facing as a vapor retarder. Thanks for thoughts and comments.
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