DIY James

Vapor Barrier Primer in Bathroom

In our new bathroom, I plan to prime the drywall (ceiling and walls) with a vapor barrier primer. Is there any reason not to do this? My thoughts are that this will help prevent the shower steam/moisture from damaging the drywall joints over time.

chfite

It won't matter. Ventilation is more important to protect from water damage. Vapor barrier is not waterproof by definition. Almost any two layer combination of latex primer and latex paint constitutes a vapor barrier.

http://www.ac5r.org/vapor_barriers.pdf

Hope this helps.