The advent of cement backer board has made it possible for do-it-yourselfers to lay tile like a pro. The reason: For most installations, it eliminates the need to set tile in a thick bed of mortar.

Q: Faucets leaked in my son-in-law’s tiled bathtub enclosure, which caused the old greenboard below them to dissolve and a few rows of tiles to come loose. I know it is virtually impossible to match ...