Preparing the substrate in wet areas is extremely important and does not differ much from preparing the substrate for other finishing materials. In the case of our HydroFest microcement, designed for bathrooms, standard waterproofing should not be used, only sealing tapes at the joints between walls and between walls and floors. HydroFest microcement is water-resistant and does not require the use of liquid film over the entire surface before application.
When applying HydroFest microcement to existing tiles, there is no need to reapply waterproofing or use sealing tapes, as it is certainly already under the tiles. However, you should remove old silicone, matt the tiles, and fill the joints, e.g. with filler.
The prepared surface should be primed and, if necessary, reinforced with a layer of mesh.
Once the primer has dried, apply two coats of HyfroFest microcement, sand and then impregnate the surface. However, before applying the varnish, we recommend using FEST Primer, which improves the adhesion of the varnish, increases resistance to water and dirt, and reduces varnish consumption.