Cement Prefabricated House Joint Leakage

The treatment of joint leakage in cement prefabricated houses requires systematic operations, with core steps including location, cleaning, repair, testing, and long-term protection. The specific treatment plan is as follows:

1. Confirm the leakage location and cause
Conduct a comprehensive inspection of the joint areas of the house, focusing on the splicing seams and edges of the prefabricated panels. Leakage is usually caused by cracks in the joints between the prefabricated panels, aging of the sealing materials, or improper joint treatment during construction. For example, long-term thermal expansion and contraction or foundation settlement may lead to joint displacement, which in turn causes cracking. If the original sealant is of poor quality or has exceeded its service life, it will also lose its waterproofing function. Precise location of the leakage points can be achieved through visual inspection, touching the wet areas, or using an infrared thermal imaging camera (if available).

2. Prepare repair materials
Select appropriate materials based on the cause of the leakage: Special joint sealant is the first choice, which needs to have elasticity, weather resistance, and waterproofing properties to adapt to the slight displacement of the joints. If the joint cracking is severe, polyurethane waterproof coating or epoxy resin adhesive can be used in combination to enhance the structural strength. The material selection should comply with local building codes, and avoid using non-specialized products such as ordinary glass glue, as they are prone to aging and cracking, leading to secondary leakage.

3. Clean the leakage area
Thoroughly treat the substrate before repair: Use a scraper or wire brush to remove the old sealant, dust, and loose particles from the joints. If there is oil on the surface, wipe it with a cleaning agent and rinse it clean. Finally, use a hair dryer or a dry cloth to ensure the joints are dry. The flatness of the substrate directly affects the repair effect. If there are uneven areas, sand them with sandpaper or fill them with leveling materials to ensure full adhesion between the sealant and the prefabricated panels.

4. Apply repair materials
Follow the material instructions: Load the sealant into a caulking gun and squeeze it evenly along the joint at a 45° angle to ensure complete filling of the sealant without air bubbles. For wide joints (over 5mm), fill them in two layers, first the bottom layer and then the top layer. After application, smooth the sealant layer with a scraper or a finger dipped in soapy water to make a smooth transition between the sealant layer and the edges of the prefabricated panels. The construction environment temperature should be between 5-35℃, and avoid rainy days or high-temperature exposure to prevent affecting the curing of the sealant.

5. Inspect and test
After repair, conduct a double verification: First, visually inspect whether the sealant layer is continuous and free of gaps. After the material is fully cured (usually 24-72 hours), perform a water spray test: Use a hose to continuously spray the joint area at a flow rate of 0.3L/(s·m) for more than 30 minutes and observe for any leakage. If local water seepage is found, mark the location and apply additional sealant.

6. Consider long-term waterproofing measures
To prevent recurrence, polymer waterproof membranes can be added below the prefabricated panels or cement-based capillary crystalline waterproof coatings can be applied to form double protection. Regularly (every 1-2 years) inspect the joint sealing status and promptly apply additional sealant to aging areas. If the house is located in an earthquake zone or an area with unstable foundations, expansion joints can be reserved and filled with elastic materials to reduce joint stress.