Condensation at tape joints
I have a relatively new home in VA, zone 4 that has a few 2nd floor walls that are adjacent to an attic space. the 2 by 4 walls were insulated with R13 fiberglass and 2 inch foam board (between the studs and attic, green stuff from lowes). Joints were taped with 3m vapor barrier tape.
I’ve noticed in Nov. , early Dec. (When the house humidity is still in the mid 40s and it drops into the 20s at night) I get a small amount of condensation behind the tape. Haven’t noticed any mold or issues directly behind the foam board.
My thought are to use a couple inches of closed cell spray foam at all the joints to prevent this in the future.
Curious of thoughts or other options from the experts?
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