The technical requirements for waterproof coatings mainly include the following aspects:
Coating thickness: The thickness of the waterproof coating is one of the key factors to ensure the waterproof effect. According to the waterproof technical specifications, the thickness of the waterproof coating for indoor bathrooms should usually reach about 5 to 2 mm. If a waterproof coating with a thickness of 5 mm is used for each coat, 3 to 4 coats are required to meet the thickness requirements. Specifically, the coating thickness of underground projects can be 1.5mm~2.0mm, and the thickness of toilets and bathrooms should not be less than 1.5mm. When the roofing project is multi-layered, the thickness of each coat should not be less than 1.5mm. When the waterproof grade is grade III, the thickness should not be less than 2mm.
Construction method: The construction method of waterproof coating includes stirring, brushing, protection and other steps. First, pour the waterproof coating into the container, then gradually add the powder, stir thoroughly for 3-5 minutes to form a uniform slurry without raw powder and particles. Use a brush or roller to apply directly on the base surface, with uniform force and no omissions; generally, it is necessary to apply twice, and the thickness of each application should not exceed 1mm. After the previous application is slightly dry, apply the next application vertically and cross-wise, and the total thickness of the application is generally 1-2mm.
Base treatment: The waterproof base must be firm, dry, flat, and free of debris. Uneven areas and cracks must be smoothed with cement mortar. Base treatment includes removing ash, oil and other attachments to keep the base firm, flat and clean; the base corners should be made into arcs, with a diameter of not less than 50mm for the inner corner and not less than 20mm for the outer corner; the base of pipes, floor drains and other details should be smoothed and polished.
Material requirements: Polyurethane waterproof coatings should have factory certificates and certification documents for manufacturers' products, and the following technical properties should be re-tested. Polyurethane waterproof coatings are shipped in barrels of component A and component B. The two components should be kept separately and stored in a ventilated and dry place indoors. When used, component A and component B are mixed in a ratio of 1:1 to form a polyurethane waterproof coating.
Environmental requirements: The construction environment temperature should be above 5°C and the humidity should not be too high. If it rains during outdoor construction, the coating should be fully dried to form a film after the rain stops, and then construction should be carried out at a temperature above 0°C.
