I live in Tennessee. Do I need a vapor barrier on the outside walls and ceiling in the bathroom I am building? Should I use green back drywall board?
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If I use green back should I use a vapor barrier? My house is not wrapped in tyvex and has a metal roof without tarpaper under the metal. The bathroom is going in on the second floor. I plan to use cement board in shower area.
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Replies
Google Red Gard.
Apply it to your cement board, fiberglass tape all seams, apply two coats to seams, one to wall, and if doing a mud base then two to the base..
As to outside moisture coming into your walls... cement board can take some... seasonally the wall should be OK... You need a good air barrier on the exterior of your home with the proper perm too.