Floor Tiling – Timber/Wood

The main consideration for laying floor tiles is the fact that once in use, they are not just decorative and hygienic but also functional. They will have to perform under daily trafficking, whether this is foot traffic in a domestic installation or heavy wear and tear in a commercial application.

It is therefore critical that full attention to correct preparation and application is paid.

With wall tiling there is not always a need for a full bed bond, but with floor tiles it is essential. The strength build-up of the adhesive is far more important too as the tiles need to be walked upon to grout, and in most cases, the floor needs to get back into service. To enable this we advise the use of powder products rather than ready mixed adhesives.

To ensure full bonding, the substrate should be as even and level as possible. In most cases, rough floors or floors with height variations can be prepared using UltraTile ProLevel One, UltraTile ProLevel Two and UltraTile ProLevel Fibre.

All offer extremely goof flow, and a floor level classified as SR2 can easily be achieved (no greater than a 5mm deflection under a 3m straight edge).

With skill an SR1 floor can be achieved (3mm deflection under a 3m straight edge). For more information on these products please contact the UltraTile Technical Department.

Plywood Overlay

A – Floorboards
B – Plywood overlay
C – Prime (remembering to use UltraTile ProPrimer neat if marine grade is used)
D – Apply adhesive (flexible only should be used)
E – Install tiles
F – Grout all joints

Backer board

A – Floorboards
B – Adhesive
C – Backer board
D – Apply adhesive (flexible only should be used)
E – Install tiles
F – Grout all joints


Unlike sand/cement screed and concrete, which are inherently strong and stable without any vibration or movement, there are different considerations to be made with timber/wooden subfloors. Existing timber/wooden floors must be strong, rigid, stable and capable of withstanding the load of adhesive and tiles. They should be sufficiently supported to prevent flexing. Additional noggins may be required to stabilise the floor. Timber/wood is prone to movement under varying levels of humidity so adequate ventilation beneath is necessary.  Identify if plywood is porous or non-porous prior to priming.

There are 2 options to enable tiling to be carried out on timber/wooden subfloors:

  1. The existing timber/wooden subfloor should be overlaid using exterior or Class 3 plywood of a minimum thickness of 15mm. All cut edges and the underside of the plywood should be sealed prior to fixing. The plywood must be screwed, not nailed, at 300mm centres.
  2. Option 2 is to overlay timber/wooden subfloors using a proprietary tile backer board. The backer board must be a floor grade product.

Follow the manufacturer’s guidelines regarding fixing it to the floor. This may include both mechanical fixing with screws and bonding with adhesive.

Regardless of which option above is selected we always advise to use a flexible adhesive and grout when installing on timber/wooden subfloors. They need not be problematic if the correct approach is carried out. If in doubt contact the UltraTile Technical Department.

Head Office

Danny Morson Way
Birch Coppice Business Park
Dordon, Tamworth B78 1SE

UK Tel: +44 (0) 1827 254 400

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Suite 1 E/F Liberty House
15 Cromarty Campus
Rosyth, Fife KY11 2YB

Scottish Tel: +44 (0) 141 260 9051
Irish Tel: +44 (0) 141 260 9053