Floor waterproofing membrane is employed to deal with damp floor problems. They are used to fully isolate the dampness from slab to the top surface finishing material such as tiles.
If the floor slab is in a very bad condition, it is better to replace it. In many situations the floor cannot be removed. A waterproofing membrane is laid above it to protect the new top floor finish from the moisture in the slab. The floor can be finished using the tiles. The following tips should be followed for tiling over the waterproof membrane:
Cleaning and Membrane Coating
Level the area to be tiled using mortar. Before applying membrane the area should be cleaned to remove all contamination including dirt oil or paint. Treat all cracks with neutral cure silicone sealant. Apply the primer missed with additive on the area to be waterproofed. Apply a coat of membrane. Install the matting for water proofing on joints and cracks. Remove all wrinkles. Again coat the waterproof membrane using a brush. The membrane layer should be about 1 mm thick. Let it dry.
Use the recommended adhesive to fix the tiles over the membrane. Mix it according to the directions. Apply the adhesive to the surface over membrane with a 10 mm notch trowel. Press the tiles over the surface in its position so that the backside of tile is adhering to adhesive. Remove any excess adhesive splashing to the surface before the adhesive dries. Allow the adhesive to set for 24 hours before putting any load on the floor.