Waterproofing Treatment for Prefabricated House Floor Slabs

Waterproofing treatment for prefabricated house floor slabs requires systematic construction, adopting multiple defense measures tailored to the characteristics of the spliced structure. The specific steps are as follows:

1. Base Layer Treatment and Defect Repair

The surface of prefabricated slabs often exhibits issues such as unevenness, sanding, peeling, and fine cracks due to construction or aging. It is necessary to thoroughly remove loose parts of the base layer and repair honeycomb pits and cracks. For example, the Shanghai Zhonghuan Jiayuan Phase I project provided a stable foundation for the subsequent waterproof layer through meticulous repair of base layer defects. This step prevents the waterproof layer from becoming hollow or cracked due to base layer defects and serves as a fundamental guarantee for the waterproofing system.

2. Rigid Filling and Reinforcement of Slab Joints

Slab joints are the primary channels for leakage and must be filled and reinforced with rigid materials such as special joint sealants to prevent repeated opening and closing displacements caused by temperature differentials or building settlement. Traditional partial joint repairs are prone to tearing and require systematic treatment of all slab joints to ensure tightness. For example, using high-strength joint filling materials can effectively resist dynamic deformation and prevent water from penetrating through slab joints.

3. Full-Area Waterproof Layer Installation

1. Material Selection: Prioritize the use of national standard thickened waterproof membranes (such as Oriental Yuhong products) for full-area coverage, or apply polymer cement-based waterproof coatings twice (with a single layer thickness ≤1mm) to ensure tight adhesion to the base layer.
2. Key Node Treatment: The waterproof layer must extend to wall corners (rounded) and around penetrating pipes (sealed with sleeves and leak stoppers) to avoid stress concentration and cracking.
3. Full-Area Defense Principle: Avoid only partial repairs; cover the entire roof area to block hidden water migration paths. Ordinary waterproof materials lack sufficient tensile and deformation resistance and are prone to cracking and failure. It is necessary to select materials that are compatible with the dynamic deformation of prefabricated slabs.

4. Special Protection for Gutter Areas

Gutters are high-risk areas for water accumulation and require reinforced protection using weather-resistant waterproof membranes and other exposed-use specialized processes to prevent material aging caused by rainwater scouring or ultraviolet exposure. For example, using highly weather-resistant membranes can extend the waterproof lifespan of gutter areas and reduce maintenance frequency.

5. Construction Process and Warranty

1. Standardized Process: Base layer cleaning → defect repair → slab joint reinforcement → full-area waterproof layer installation → gutter reinforcement → water closure test (accumulate water to 20cm and inspect for leakage for 24-48 hours).
2. Warranty Requirements: It is recommended to provide a warranty of 5 years or more after completion and to achieve long-term resolution of leakage problems through regular inspections and maintenance.

Precautions: Subsequent renovations must avoid damaging the waterproof layer, such as prohibiting drilling holes or stacking heavy objects on the roof; the water closure test is a critical acceptance step, and leakage points must be strictly recorded and promptly repaired.