Water Accumulation on the Roof of Container Houses

The main causes of water accumulation on the roof of container houses include unreasonable drainage system design, roof structural deformation, failure of the waterproof layer, and construction defects, etc. Targeted measures such as optimizing drainage, repairing the structure, and redoing the waterproofing are required to resolve these issues.

Unreasonable Drainage System Design

If the roof gutter has no horizontal slope or the outlet design is unreasonable, water cannot be discharged during heavy rain, potentially flowing back into the eaves gutter. For example, inadequate anti-corrosion treatment of the gutter can lead to rust and erosion, or debris blocking the outlet can result in water accumulation or backflow. Solution: Clean the gutter and downspouts to ensure smooth drainage; adjust the gutter slope (recommended ≥2%) and add additional outlets; perform anti-corrosion treatment or replace materials on rusted parts.

Roof Structural Deformation

The panels of container houses may deform due to external loads (such as wind, snow, thermal expansion and contraction) or material aging, causing cracks at the joints to expand and damaging the original waterproof layer. For example, when installing fans or exhaust pipes on the panels of movable houses, if the waterproofing of the surrounding cracks is not properly handled, it can easily lead to leakage. Solution: Reinforce the base structure and repair the deformed panels; create V-shaped grooves in the cracks and fill them with elastic sealant or grout for leakage repair; add expansion joints to accommodate material shrinkage.

Aging or Damage to the Waterproof Layer

Substandard quality of waterproof materials or construction defects (such as loose joints) can lead to aging and cracking of the waterproof layer, directly causing water seepage. For example, walking on the roof of a container house can loosen fasteners, and aging of the waterproof pad can result in leakage. Solution: Completely remove the old waterproof layer and use high-quality materials (such as SBS modified bitumen membrane) to redo the waterproofing, ensuring a joint width of ≥10cm; use a "sleeve + sealant" dual treatment for detailed nodes such as pipe roots, and add additional waterproof layers at corners such as the parapet wall.

Construction Defects

Failure to properly handle key nodes (such as pipe roots, connections between the ridge and eaves) during construction or the use of inferior materials can lead to later leakage. For example, if the connection between the skylight and the main structure is not firmly welded or sealed, it may hinder the flow of rainwater into the drainage system. Solution: Rework the defective construction parts and repair them with UV-resistant/weather-resistant sealant; optimize design parameters (such as ridge slope, skylight panel position) to avoid water retention.