Tiling Over Plywood Underlayment

For residential use one form of underlayment the tile council of north america s handbook allows is plywood over joists that are 16 in.

Tiling over plywood underlayment.

Begin by applying the thin skin adhesive to the plywood with a smooth trowel. No matter how firm the subfloor. This prepares and seals the surface for the. Void free underlayment grade panels which both stiffen the existing floor and provide uniform support to prevent cracks in the tile above.

Tape off any affected vents with painter s tape. Use intervening layers of two sheets of plywood. The go to product is 1 2 in. Roll on a layer of latex primer sealer.

Fill seams in the subfloor with caulk. A tapered piece of plywood may be difficult to fabricate and may not offer the support required for a good installation. Step 5 skim coat the paper. Once the surface is completely covered cover the adhesive with the fiberglass based paper and smooth out any wrinkles or bubbles with a broad drywall knife.

On a plywood subfloor you need either a layer of cement backer board or an underlayment membrane like custom building products wonderboard and redgard between the subfloor and tile for the thin set adhesive to achieve a good bond. While tile can be laid on plywood do not install tile directly onto the plywood subfloor itself. Once properly in place and cured the tile can be installed. If the structure is adequate the use of a cement based floor patch that allows for the needed height may be the best choice.

The plywood will expand and contract at a different rate as the tile causing cracks to develop in the grout lines or tiles over time.