Vapor Drive Help – GreenBuildingAdvisor

CZ 3A/4A (North GA area)

2001 gut reno

Vapor drive is a subject I still don’t have a full grasp on, so I’m looking for help in determining if this wall assembly in our attic is a possible moisture issue.

Our HVAC closet in the attic (attached to a finished bonus room above living space) will be air conditioned. Our HVAC guy decided to use plywood as the interior walls in that closet.

The rest of the wall assembly will likely be fiberglass batts on the attic side and Tyvek commercial wrap (leftover from the exterior) carefully detailed to be our attic side air barrier. The rest of the bonus room with be drywalled on the interior side.

Being in a mixed/hot humid climate would mean the vapor drive would be predominantly inward, correct?

If so, would that cause an issue with the interior finish of that closet being plywood instead of drywall? The closet size is about 40-50 sq ft.

I know plywood is less vapor permeable than drywall, and we don’t want to cause any potential condensation and mold risks. We came from a moldy home before and it caused severe illness in my family, so we’re doing everything we can to try to avoid those issues.