Civil Work Rule Book

British Standards BS 5385 Part 1 states that plywood is not a suitable base for the direct fixing of wall tiles, therefore when tiling onto walls, a tile backer board is required. Many underlayment options exist, but cement backer boards or uncoupling membranes are a good choice for most tile installations.

Here are some tips for fixing tile skirting over a plywood wall : 

Prepare the plywood: Before fixing the plywood, seal the edges and reverse side with a product like BAL Bond SBR to reduce water permeability. You can also prime the plywood to protect it from moisture, which can cause the board to swell. 

Leave an expansion gap: Leave a 2-3 mm gap around the room's perimeter to allow for movement. Fill the gap with silicone sealant to prevent it from filling with tile adhesive. 

Use a flexible adhesive: Use a flexible powdered adhesive instead of a premixed tub. 

Create ridges with adhesive: Use a notched trowel to create ridges in the adhesive on the wall. This helps distribute the adhesive evenly and increases the chance of the tiles being aligned correctly. 

Use thicker plywood: Thicker plywood reduces movement under the tiles. 

Avoid applying tile directly to plywood : Plywood expands and contracts at a different rate than tile, which can cause cracks in the grout lines or tiles over time.

Tanmay Das 30th August 24