Leakage of Prefabricated Panel House Roof

The leakage of prefabricated panel house roofs requires a systematic renovation solution, as traditional local repairs are difficult to completely resolve the issue.

The leakage problem of prefabricated panel roofs has significant structural characteristics, primarily stemming from their spliced construction. Prefabricated panels are assembled from multiple independent concrete slabs, with the panel joints forming a continuous structure. Over time, affected by temperature variations, building settlement, and roof loads, these panel joints continuously open and close, causing displacement. Ordinary waterproofing materials (such as thin-layer coatings and non-standard membranes) are prone to cracking or delamination due to insufficient tensile and deformation resistance, creating persistent water infiltration channels. Additionally, the surface of prefabricated panels often exhibits基层病害 (sub-base defects) such as unevenness, sanding, peeling, and fine honeycomb cracks. Rainwater can flow along the panel joints and sub-base gaps beneath the waterproofing layer, resulting in a mismatch between the leakage points and the actual water infiltration locations, highlighting the issue of concealed leakage.

Traditional local repair techniques (such as joint sealing and surface gluing) only address superficial symptoms and fail to resolve the root causes of dynamic joint displacement and sub-base defects. For example, simply filling the panel joints without reinforcing the joint structure can lead to material cracking again due to frequent deformation. Similarly, merely applying waterproof coatings on the surface without repairing sub-base defects allows rainwater to still penetrate through sub-base gaps, keeping the re-leakage rate high.

A systematic renovation solution should be implemented in steps:

1. Full Roof Clearance: Thoroughly remove the existing waterproofing layer, debris, and loose sub-base to ensure a flat and solid construction surface, preventing poor adhesion between new and old materials.
2. Precision Repair of Sub-base Defects: Level uneven areas, address sanding and peeling, and fill fine cracks and honeycomb holes to eliminate pathways for rainwater infiltration.
3. Rigid Joint Filling and Reinforcement: Use high-strength rigid materials (such as polymer mortar) to fill the panel joints, enhancing their resistance to displacement and reducing the risk of cracking due to deformation.
4. Full-area Protection with National Standard Thickened Membranes: Lay thickened waterproofing membranes that comply with national standards across the entire roof area, forming a continuous waterproofing barrier to resist rainwater penetration.
5. Specialized Exposed Waterproofing for Gutters: For areas prone to water accumulation, such as gutters, use weather-resistant exposed waterproofing materials for targeted treatment, extending the service life of the waterproofing layer.

This solution systematically addresses the shortcomings of prefabricated panel roof leakage through structural reinforcement, sub-base repair, and full-area protection, significantly reducing the re-leakage rate and improving roof waterproofing performance.