is it ok to use flat ceiling paint on a bathroom ceiling?
Not a typical choice. Check with a pro paint store like Sherwin Williams or Benjamin Moore? They may have a non reflective paint that would serve well in the bathroom. I am assuming you want flat sheen due to not wanting to draw attention to some sort of surface texture or surface variation, like from repairs/damage?
I feel differently. No reason not to use a flat ceiling paint in a bathroom. Just like in any other room, the flat will help hide imperfections. Even in the high humidity area like a bath, flat paint will stay on just as well as any other finish.
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