The substrate to be treated must be mechanically robust and clean. Remove all cement laitance, traces of powder, flaky parts, grease, oil, and form release agents by sandblasting or washing down with a high-pressure water pump. If the substrate to be waterproofed and protected with Aquashield PU 100 is in poor condition, remove the damaged parts manually or mechanical abrasion by using a hydro-demolition system or a hydro-scarified. The last technique, which uses high-pressure water, is recommended because the reinforcement rods are not damaged. The structures that are not subject to vibration could cause small cracks in adjacent concrete. Once the rust has been entirely removed by sandblasting, repair with a pre-blended repairing mortar. Absorbent surfaces to be treated with Aquashield PU 100 must be primed with Seal Primer. Existing floors, which are covered in tiles, must be well bonded to the substrate, and the surface of tiles must be free of substances that could compromise the adhesion of Aquashield PU 100, such as oil, grease, paint, wax, etc. In order to remove material that could affect the adhesion of Aquashield PU 100, clean the floor with detergents and water. After this, the surface must be treated with Epoxy based Primer.