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My roof has shingles but no underlay or barrier underneath. I’m planning to convert the attic into an office and was going to put up drywall. Should I add something first to protect the drywall from moisture in case water ever leaks through the shingles?

I’m planning a bathroom renovation and was wondering if it’s okay to install new tiles directly over the old ones or if it’s better to remove them completely first. The existing tiles are in decent shape and still well stuck to the wall, but I’m not sure if tiling over them would cause problems down the road with weight, adhesion or moisture. Has anyone done this? And what would you recommend?

If one has a color on walls not available because originally a valspar color from Lowes what does one do or what options is there?