Hi - I'm a new first time homeowner and am so thankful to find a place like this! I have noticed a problem in my bathroom and want to fix it quick before it becomes even more of an issue. Here it is... There is an arch over my bathtub (see the picture for reference). To the best of my knowledge this arch is drywall - nothing special to account for moisture. The paint on the underside of the arch is starting to peel and bubble (see pictures). I cannot see any evidence whatsoever of mold at this point, but I want to take care of this before it gets any worse. My question is this, can I sand and tile this archway even though it is drywall? I've read conflicting things about tiling over drywall in a shower. This is not exactly in the shower, but it is frequently exposed to moisture/condensation, so pretty much the same thing. If the answer is yes, tile over it, what is the best way to go about doing that (do I need to use some kind of waterproof sealant, special grout, etc?) If the answer is no, don't tile over it, how could I fix it instead? Thanks for the advice!!