Tiling onto floors using an uncoupling system

A – Load bearing substrate
B – Prime
C – Adhesive
D – Uncoupling membrane
E – Apply adhesive (selected upon tile type)
F – Install tiles
G – Grout all joints

Uncoupling systems are an excellent method of fixing tiles in very testing environments. The science behind uncoupling can be summarised as:

“A system used to isolate the finished tiled floor from the subfloor to prevent damage from lateral movement, subfloor cracking and water penetration.”

Systems generally involve the use of a profiled polyurethane may with a fleece underside which is bonded to the substrate using a flexible adhesive. Tiles are then bonded to the mat using a flexible tile adhesive and grout. For full information on how these systems work and the installation methods required, please refer to the manufacturer’s instructions. However, the following general criteria should always be met:

  1. The substrate must be even, rigid and load bearing.
  2. Boarded floors (timber or backer boards) must be screwed down as per instruction, and replace any boards that are damaged. Uncoupling mats will accommodate lateral movement, but are not designed to withstand vertical movement, so subfloors must be braced to make them sound and strong. All timber floors must have adequate under floor ventilation to prevent the timber from moving, post installation, due to humidity changes.
  3. Tile selection should be made on the basis of the likely load that the flooring will be subjected to i.e. thickness and strength in accordance with end use expectations.
  4. Prime the subfloor, if required, with the appropriate primer.
  5. The anchoring fleece should be bonded using adhesive. The adhesive must bond to the substrate and mechanically anchor the fleece to the underside of the mat. We would recommend using a 4mm notched trowel with flexible adhesive.
  6. Once the mat is secure the tiles can be fixed using an UltraTile flexible adhesive. It is advised that the cavities in the matting are first filled with adhesive using a smooth edge towel before finally applying with a notched towel to achieve the bed thickness required.
  7. Grouting should be carried out using UltraTile FlexJoint grout.