With joists every 24 inches, you need 1-1/2-in. If your floor is too thin for tile, add a thicker layer of tile backer board. Our floor required 1/4-in.-thick backer. Yours might need 1/2-in.

Install a moisture barrier if you're covering tile in a bathroom, kitchen, laundry room, or area with concrete floors. Then, place the laminate floor underlayment, which is a padding layer that ...