Tiling onto different surfaces

Tiling and installing underfloor heating onto different surfaces can require different installation techniques. Firstly you need to ask the question what subfloor type do i have?

There are 3 main types of subfloor in the uk.

1- Sand and Cement Screeds
2- Floorboards laid onto timber joists
3- Chipboard laid onto timber joists

Sand and cement screeds

Preparation of the Base
Firstly it is important that the screeded floor is not starting to break up and that there are no large cracks or gaps that would require filling before work commences - we recommend the use of our levelling compounds. The surface must also be flat enough to permit good quality tiling without excessive use of tile adhesive.

It is important to note that new screeds take some time to dry out fully. In most cases this equates to 1inch of screed per week drying time which means a average screed will take 2 to 3 weeks to dry out.

If you are intending to install underfloor heating under your tiles we recommend the use of tile backer insulation boards as underfloor heating installed directly onto a concrete base can be inefficient. Insulation board must be stuck to the surface with flexible tile adhesive.

Once the tile adhesive has dried under the insulation boards then the underfloor heating may be installed.
 
The tiles may be then be fixed using a 5mm notched trowel, it is important that no voids be left beneath the tiles. If using underfloor heating we recommend using latex self levelling compound over the heating cables first. This prevents movement of the underfloor heating during installation, protects the heating elements from damage and makes the job of tiling much easier.

Floorboards laid onto timber joists

Preparation of the Base
Although some products are available that allow tiling directly onto floorboards we do not recommend this installation method, particularly if installing underfloor heating.

We recommend either fixing a suitable thickness plywood over the floorboards, or fixing a tile backer insulation board. Where possible insulation board should be used (especially with underfloor heating) as this provides the most suitable surface for both underfloor heating and tiles. If using plywood you may use 150w heating mat or if using tile backer boards you may use 200w heating mat.

Insulation board must be stuck to the surface with flexible tile adhesive if using 6mm thick boards or may be screwed down using washers if using 10mm tile backer board.

Once the tile adhesive has dried under the insulation boards then the underfloor heating may be installed.
 
The tiles may be then be fixed using a 5mm notched trowel, it is important that no voids be left beneath the tiles. If using underfloor heating we recommend using latex self levelling compound over the heating cables first. This prevents movement of the underfloor heating during installation, protects the heating elements from damage and makes the job of tiling much easier.

Chipboard laid onto timber joists

Preparation of the Base

Most chipboard floors wil be suitable for tiling onto and installing underfloor heating.

However we recommend either fixing a suitable thickness plywood over the chipboard, or fixing a tile backer insulation board. Where possible insulation board should be used (especially with underfloor heating) as this provides the most suitable surface for both underfloor heating and tiles. If using plywood you may use 150w heating mat or if using tile backer boards you may use 200w heating mat.

Insulation board must be stuck to the surface with flexible tile adhesive if using 6mm thick boards or may be screwed down using washers if using 10mm tile backer board.

Once the tile adhesive has dried under the insulation boards then the underfloor heating may be installed.
 
The tiles may be then be fixed using a 5mm notched trowel, it is important that no voids be left beneath the tiles. If using underfloor heating we recommend using latex self levelling compound over the heating cables first. This prevents movement of the underfloor heating during installation, protects the heating elements from damage and makes the job of tiling much easier.