If the house is older and has a few coats of oil paint you are ok. If you
pull down the drywall there to put up a vapor barrier then you might as well
continue on to do the rest of the house too, also the exterior walls.

Gary

"Sasha" wrote in message
ups.com...
I am remodeling my upstairs bath. I removed all walls to put Durock. I
don't want however remove ceiling as it is more or less in good shape.
The ceiling does not have any vapor barrier right now. I heard once
that some sort of oil based or another primer makes acceptable vapor
barrier. Is it true? I checked attic insulation and didn't find any
condensation there.