Installing tile directly over raw plywood is a recipe for failure. Wood is a hygroscopic material, meaning it expands and contracts with changes in humidity and temperature. Because tile and its mortar are rigid, they cannot accommodate this movement. If tiled directly onto wood, the inevitable expansion of the plywood will cause the tiles to crack, the grout to fall out, and the bond to fail as the floor flexes. To bridge this gap, industry best practices require an intermediate layer. This usually consists of a cement backer board (such as cement board or fiber cement board) or a decoupling membrane installed over the plywood. These materials isolate the tile from the wood's movement, allowing the tile floor to remain stable even as the building materials underneath shift. When using these products, it is critical to follow the manufacturer's specific guidelines regarding fastener spacing, tape usage, and mortar type. If your current subfloor is plywood, consult a professional to ensure the correct underlayment is selected to support the specific tile type you have chosen.
Key considerations
- tile over plywood
- can i tile on plywood
- subfloor for tile
- Plywood Subfloor
- Cement Board
- Decoupling Membrane