How To Prep Cement Board For Tile In Shower

How to Prep Cement Board for Tile in Shower

Installing tile in a shower requires proper preparation of the cement board underlying the tile. Cement board is a moisture-resistant material that provides a stable surface for tile adhesion. Prepping cement board for tile involves several essential steps to ensure a secure and durable installation.

1. Remove Existing Fixtures and Surfaces

To prepare the cement board, begin by removing any existing fixtures or surfaces, such as old tile, grout, or drywall. Use a pry bar or utility knife to carefully remove these materials, ensuring not to damage the studs or other supporting structures.

2. Install Cement Board

Cut the cement board to the appropriate size and shape for the shower area. Use galvanized screws to secure the cement board to the studs, spacing them evenly at a maximum distance of 8 inches apart. Ensure the cement board is flush with the studs to provide a level surface.

3. Tape and Thinset the Joints

Apply fiberglass mesh tape over the joints between cement board panels. Use a trowel to spread thinset mortar over the tape, ensuring a thin and even layer. Allow the thinset to dry completely before proceeding.

4. Apply Scratch Coat

Spread a layer of thinset mortar over the entire cement board surface, using a trowel with notched edges. This "scratch coat" provides a rough surface that enhances the adhesion of tile. Allow the scratch coat to dry for at least 24 hours.

5. Score the Surface

Once the scratch coat is dry, lightly score the surface with a utility knife. This creates small grooves that allow the setting material to penetrate the cement board and form a stronger bond.

6. Apply Primer

Apply a coat of acrylic primer to the cement board surface using a paint roller. Allow the primer to dry thoroughly before installing the tile.

7. Trowel on Thinset Mortar

When ready to install the tile, spread a thin layer of thinset mortar over the primed cement board surface using a notched trowel. Ensure the mortar is evenly distributed and free of humps or hollows.

Conclusion

Preparing cement board for tile in a shower ensures a strong and durable installation. By following these steps meticulously, you can create a stable base for tiling that will withstand moisture and wear and tear over time.