Wall Cracks in Prefabricated Panel Houses

Wall cracks in prefabricated panel houses require significant attention as they may pose safety hazards. To assess the danger level, it is necessary to consider the width, location, and changes of the cracks comprehensively. Measures such as applying for an appraisal and having the property owner make rectifications should be taken in accordance with relevant regulations.

Causes of Cracks

• Low structural strength of the house: Prefabricated panel houses are assembled from prefabricated panels, inherently lacking in robustness and toughness. They often adopt a hollow design, with the quantity and distribution of steel bars being less scientific and reasonable compared to cast-in-place houses. Their earthquake resistance is poor, and even slight vibrations can loosen the joints between floor slabs, leading to an increase in the number and size of cracks over time.
• Service life factors: The service life of prefabricated panel houses is relatively short, with various problems likely to arise after 20 - 30 years. As time goes on, issues such as wall cracks will gradually become apparent.
• Other problems causing cracks: Wall water seepage and steel bar corrosion can also lead to wall cracks. For example, some prefabricated panel houses may experience heavy rain inside when it rains outside, with mottled walls that eventually develop cracks.

Assessing the Danger Level of Cracks

• Width: If a crack exceeds 1 millimeter, special attention is required; if it exceeds 2 millimeters, it is very dangerous.
• Location: Cracks that appear in structural elements such as load-bearing walls and main beams pose a higher risk.
• Changes: If cracks branch out like tree branches or if the steel bars are exposed and rusted, professional agencies must be contacted immediately for handling. If you suddenly hear a 'clicking' sound and the crack visibly widens, evacuate immediately. Normally, you can use a coin to measure the width of the crack and stick paper strips with dates at both ends of the crack. If the paper strips tear apart after a period of time, it indicates that the house is deforming and requires immediate handling.

Handling Measures

• Apply for an appraisal: According to relevant regulations, after a house is delivered for use, the owner or user should apply to a house safety appraisal agency for an appraisal.
• Property owner rectification: The property owner should fulfill its main responsibilities and make rectifications in accordance with relevant regulations.
• Enhanced property management: Property management companies should strengthen daily inspections, set up safety warning lines, post notices and warning signs, and regularly monitor potential hazard areas. If the property management company is unable to undertake maintenance tasks, the community party committee can arrange for grid members to conduct regular inspections and post safety hazard notices downstairs to inform residents of the situation.