Stone floor tile installation information

Allow these screeds to dry thoroughly following manufacturer’s guidelines before installation
of stone takes place. These screeds tend to hold moisture longer than standard sand and
cement screeds. Fixing should not take place until the residual moisture content of less than
0.50%. You can install using Alea stone decoupling membrane when the screed has a
residual content of less than 2.0%. Before installation takes place laitance which may be
left on the screed should be removed and the surface sanded or keyed to make sure the
adhesive will key to the screed. The screed must then be sealed using the minimum of 2
coats of Dunlop Primer.

Underfloor Heating Screed (water piped system)

Once the screed is dry it must be heated slowly at a rate of 5 Centigrade per 24 hours to  a temperature of 25 Centigrade and maintained for 3 days, before being allowed to coolto room temperature. The heating must be turned off for tiling. If cracks appear in the screed you should use Alea decoupling membrane which will bridge cracks stopping them appearing in the stone. Once the tiling is complete ensure the heating is not turned on for 14 days before bring the heating up to to temperature at a maximum rate of 5 Centigrade a day.

Underfloor Heating Screed (electric mat or cable system)

We recommend you install the heating system on Alea Tile backer board this will reflect the
heat up and reduce the running cost of the heating system. The best method of tiling on this
system is to lay the mat then put 2 coats of universal levelling compound on top, this will
secure the mat in place and reduce the risk of damaging the heating elements when tiling
the floor. You can then directly install on the floor using a suitable flexible adhesive. Once
the tiling is complete ensure the heating is not turned on for 14 days before bring the heating
up to to temperature at a maximum rate of 5 Centigrade a day.

All timber type floors will be subject to movement under load, temperature and humidity. It is important that the wood floor must be rigid. Tiles are rigid and do not bend or flex, therefore
if they are subjected to stress from the background they may eventually break. Therefore existing floorboards, chipboard or MDF will require an overlay of exterior grade WBP plywood. Advice should be sought on thickness required. The plywood sheets should be sealed on their reverse side, face and edges with neat Dunlop Universal Bonding Agent. The sheets should be laid in a staggered fashion. Dunlop recommend that you use a minimum of a 15mm exterior (WBP) plywood which is screwed at 300mm centres to an existing timber floor. Dunlop Single Part Flexible Adhesive and Grout should then be used. Alternatively you can install Alea Decoupling Mat, this will deal with some movement. The floor still needs to be rigid. The mat is fixed with Dunlop Grey Thick Bed Adhesive applied with a 3 -5mm notched trowel.

Existing Tile Bases

All loose tiles should be removed and the remaining floor should be degreased and free of surface contaminants. Professional advice is recommended. Priming and sealing of the floor may be needed we recommend you speak to our technical specialist.