I have a drop wallboard ceiling over the tub, with a shower head out of the ceiling. I've been told the ceiling should be fine by multiple trades people. I still would like to be prudent when painting it, to avoid moisture/mildew problems.
It will be painted with BM Spa & Bath which should help. I am also wondering if a prime coat of Gardz to seal it all off would also work to seal out moisture and protect the wallboard. Seeing the finish it puts on a wall, it would seem so. Is it alright to use Gardz for this purpose?
Gardz is pretty cool stuff. Almost as good a vapor barrier as an oil- plus top coats love to stick to it. I know of contractors who prime all their bare sheetrock with it- makes for great base particularly for eggshell or more top coats.