The old tile floor has been removed and you want to create a waterproofing layer before laying the tiles. How to do?
1.Complete cleaning of the substrate (slab) from crumbly parts, dust, etc.
2. Creation of a new screed with the appropriate slopes.
3. After curing, apply with a spatula a first layer of about 2 mm of ELASTOPROOF 639 (così mixed: add ELASTOPROOF B639 to the liquid in a ratio of three parts A639 with one part B639, stirring accurate until a homogeneous and lump-free mixture is obtained). For a better result, it is recommended to insert a 60 g / m2 alkali-resistant fiberglass mesh in the first layer. On the first hardened layer (after 5/6 hours) apply a second layer of about 2 mm. Do not apply over technical joints.
4. After curing, at least after 5/6 days, lay the new floor (ceramic, stoneware, klinker, etc.).
Limit the intervention to the cantilevered terraces in the absence of underlying compartments. Respect any presence of structural joints. On large surfaces create adequate joints.