Tiling to Timber sub floors

Here is a general guide to our recommendations for tiling to timber.

The most important thing, when tiling to timber floors is to ensure that the floor is sufficiently rigid and stable enough to support :

1. The weight of tiling.
2. The amount of traffic i.e. foot or otherwise.

Recommended fixing centres are (300mm etc), however I would suggest that a 6mm thick proprietray board would not add that much more additional strength, in terms of rigidity (i.e amount of deflection within the existing timber floor), but as a general rule of thumb will normally provide a better surface to receive ceramic tiles.

Our recommendations would always be, when applying an overlay of less than 15mm thick plywood (as recommended in BS 5385-3) that providing there is no obvious movement or "bounce" in the floor simply by walking upon it, to use an elastomeric adhesive such as the new BAL Single Part Fastflex.

Joints between the tiles may be filled with BAL Wide Joint Grout with BAL Admix GT1 (Diluted 1:1 by volume with water).

If required, even though the floor is small, if you are concerned that the floor is still moving too much even with a 6mm No More Ply overlay (or any other board for that matter), that a minimum 15mm plywood overlay is applied to the existing timber floor, which should then allow tiling to be carried out with either BAL Single Part Flexible or BAL Supercover Rapid Flex

Joints between the tiles may then be filled with BAL Superflex Wide Joint Grout (equivalent to BAL Wide Joint Grout with BAL Admix GT1 diluted 2:1 by volume with water).

In conclusion, if the adhesive is not elastomeric , then the adhesive may be able to deform when subjected to deflection but will allow the movement to be transferred directly to the tiled finish, therefore there is an increased risk that tiles could crack, if the movement was significant enough.

An elastomeric adhesive such as BAL Single Part Fastflex will be able to offer additional protection by absorbing some of the floor movement within the adhesive itself thus helping to further protect the tiling layer above as well as maintaining the bond between the adhesive and tile. This therefore will provide additional assurances regarding longevity of tiling.

For more information ask a question on the TilerWorld Forum