Analysis of Eight Major Reasons Why Prefabricated Houses Leak

1. Inappropriate selection and aging of waterproofing materials during the construction of prefabricated houses .

2. Careless construction at key points. Pipes extending from the roof and vents were not properly sealed at their bases; the waterproofing layer's flashing height was insufficient. During rain, the ventilation channels became clogged, and improperly placed ventilation holes caused the insulation layer to be submerged in water for extended periods.

3. The prefabricated houses were constructed using substandard materials, and the construction process was arbitrary and did not strictly follow the construction specifications.

4. Poor waterproofing treatment at the cracks around the openings in the prefabricated house panels and the installation of various fans, exhaust pipes, etc.; during the use of the prefabricated house, due to the influence of external environment, wind load, snow load, thermal expansion and contraction, etc., the roof panels are deformed, causing the cracks at the joints to expand, destroying the original waterproofing treatment and resulting in water leakage.

5. Due to the large span of the roof panels, the installation at the joints of the roof panels often fails to meet the design standards, leading to leaks.

6. During the installation of prefabricated houses, care was not taken to protect the installed color steel panels, and the roof was trampled on at will, which damaged the flatness of the roof.

7. In prefabricated houses, the gutters lack horizontal slope, and the gutter outlets are poorly designed. During heavy rain, water accumulates in the gutters and backflows into the inner eaves gutter. Inadequate anti-corrosion treatment of the gutters during construction can lead to rust and corrosion, or debris can clog the outlets, all of which can cause leaks or backflow. Prefabricated houses should not have horizontal slopes in their gutters; a slope of at least 0.5 % should be provided during installation. Gutter joints should also be free of gaps, incomplete welds, slag inclusions, or lack of anti-corrosion treatment.

8. During the installation and use of prefabricated houses, walking on the roof can cause fasteners to loosen. Aging of the fastener waterproofing gaskets can also lead to leaks at the fastener points.

When a prefabricated house leaks, it is best to have it repaired by a professional manufacturer to ensure its continued normal use.