I believe I have myself very confused on vapor retarders. I have read many articles and codes, and I am now more confused than when I started.
Climate Zone 5.
We we have Un-Vented cathedral with closed cell spray foam.
We also have 2 vented attics with blown in fiberglass, topped with cellulose for better air sealing.
All the walls have open cell spray foam.
No vapor barriers were added, such as polyethylene. We have painted walls and ceilings, which I thought was enamel paint but just learned it is actually acrylic.
I have read closed cell spray foam is class 2 vapor retarder, but I am very unclear as to what to do, if anything, with the open cell walls and the vented fiberglass attics.
i would hate to cause problems by adding vapor barriers if not needed.
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