Leakage at the Eaves of Prefabricated Panel Houses

The core causes of leakage at the eaves of prefabricated panel houses are water seepage through panel joints due to the spliced structure and concealed leakage caused by underlying layer defects, which require treatment through covering joints with flexible waterproof materials and strengthening underlying layer treatment.

Analysis of Leakage Causes

The root cause of leakage at the eaves of prefabricated panel houses lies in their spliced structural characteristics. Panel joints are the main channels for water seepage: Prefabricated panels are installed through splicing, and natural gaps exist at the panel joints. Over time, affected by temperature differentials, expansion and contraction, and building settlement, the panel joints will continuously open and close, causing ordinary waterproof materials (such as rigid coatings) to crack and delaminate due to insufficient tensile strength, resulting in continuous water seepage. Concealed leakage is common: The underlying layer of the prefabricated panel surface may have defects such as cracks and hollowing. Rainwater will flow freely beneath the waterproof layer along panel joints or underlying layer gaps, causing the leakage point (such as the indoor ceiling) to not correspond to the actual water seepage point (such as the panel joint at the eaves), increasing the difficulty of repair.

Core Treatment Concepts

To address the above issues, treatment should follow the principles of 'flexible covering, overall sealing, and adaptability to deformation'. Prioritize the use of flexible waterproof materials: Rolled waterproof materials (such as SBS modified asphalt rolls and polymer self-adhesive rolls) have good elongation and overall strength. They can cover the entire floor surface, especially above the spliced joints, forming a continuous waterproof barrier and effectively resisting minor deformations of the panel joints. Strengthen protection in harsh areas such as gutters: Due to long-term water accumulation and ultraviolet exposure, gutters require the use of specialized waterproof processes that can be exposed to the elements (such as weather-resistant rolls + sealant edging) to prevent material aging and cracking.

Key Construction Points

1. Accurately locate leakage points: Determine the water seepage path through water injection tests (injecting water onto the roof to observe leakage points) or infrared thermal imaging (detecting temperature differences to locate concealed water seepage) to avoid blind construction.
2. Strictly treat the underlying layer: Clean dust and oil stains from the panel joints and underlying layer surface, ensuring they are dry and free of visible water; repair defects such as cracks and hollowing to enhance the bonding strength between the underlying layer and the waterproof layer.
3. Material selection and construction: Select rolls with an elongation of ≥300%, paired with flexible sealants or waterproof coatings as auxiliary materials; during construction, use the 'hot-melt method' or 'self-adhesive method' to ensure tight bonding between the rolls and the underlying layer, with a focus on treating panel joint intersections and internal and external corners.
4. Finished product protection and acceptance: Avoid stepping on the waterproof layer after construction. Conduct a closed-water test (for more than 24 hours) after complete curing to confirm no leakage before proceeding with subsequent protective layer construction.