Tiling on a wood substrate

Ceramic Tiles and Wood often do not make for good partners. The reason for this is that timber constantly moves, changes shape and flexes. Changes in humidity in the environment can warp, bend and change the shape of wood. On the other hand, ceramic tiles are inherently brittle and rigid. When tiling over a wood substrate, it is crucial to take potential sources of movement into account.

Wooden floors will typically bend under load. This can be a critical error when tiles are being walked over. If the adhesive is not flexible to absorb the movement, the tiles can crack. Temperature and humidity changes can cause expansion and contraction in the wooden floorboards. Moisture can also cause the wood to swell, which can be a huge issue in wet locations, such as bathrooms.

To combat this, Kerakoll have invented an adhesive which takes the continued movement of timber into account. HC40 Eco Rapidflex is an eco-friendly, single-component adhesive, which provides an ideal, final solution for the application of all types of wall and floor tiles on timber substrates.

Grey regal floral patterned tiles in a bathroom

Preparation of wood substrates:

Make sure that the floor is able to bear the added weight of tiles and whichever dynamic loads that may be applied to the area. This includes, but is not limited to, walking on the tiles and placement of furniture on tiled surfaces. It may be necessary to strengthen the structure by inserting reinforcement noggins between the beams. Appropriate 18mm plywood panels should be placed before laying the tiles. These panels must be fastened to the substrate with screws, whilst avoiding damaging the substrate or any of its reinforcements. This panel should then be cleaned to remove any dust and debris that may have occurred during the installation. If Ply is not suitable, then ditri decoupling matting should be used. At this stage, it is important to ensure that if the panels have been treated with fire or waterproofing materials, that this treatment will not restrict the adhesion of the adhesive.

The plywood boards should then be primed with Arc Tilers Primer diluted 3 parts water to 1 part primer and allow to dry. The surface may then be tiled on, following our Tile a Wall or Tile a Floor guidesBrown rustic tiles in a bathroom paired with a subwall of cream.