House Survey on Prefabricated Panels

House surveys on prefabricated panels should be conducted from three aspects: hidden safety hazard investigation, safety level assessment, and identification of whether the panels are prefabricated.

Preliminary Investigation of Hidden Safety Hazards

1. Cracks at the bottom of the panel: Look up at the ceiling (the bottom of the prefabricated panel) to check for horizontal through-cracks or obvious cracking at the joints between panels. The presence of such cracks may affect the structural safety of the floor slab.
2. Deflection deformation: Check for obvious signs of downward bending or sinking in the middle of the floor slab. Excessive deflection deformation can lead to a decrease in the load-bearing capacity of the floor slab and may even trigger a collapse accident.
3. Damage at the ends: Examine the positions where the two ends of the prefabricated panel rest on the walls, and observe whether the concrete is loose, crumbling, or if the steel bars are exposed and rusted. Damage at the ends can weaken the connection strength between the prefabricated panel and the wall, affecting the overall stability of the house.
4. Node connections: Pay attention to whether the support of the prefabricated panel on the wall is firm and whether there are signs of looseness. According to regulations, the support length of the prefabricated panel on a brick wall should not be less than 80mm. At the same time, check for disengagement or cracks at the corners and intersections of the walls to ensure reliable node connections.

Assessment of House Safety Levels

At the beginning of 2026, the housing and construction department completed the investigation and filing of prefabricated panel residential buildings across the country. According to the 'Standards for the Appraisal of Dangerous Houses', Class A and Class B together account for 72%, Class C accounts for 25%, and Class D accounts for less than 4%. Among them, Class A structures are intact, with no dangerous points found in the load-bearing components, and the house is generally safe; Class B structures are basically intact, with minor issues in individual components that do not affect the safety of the main structure; Class C structures have some load-bearing components that do not meet the standards, with local dangers, constituting partially dangerous houses, and policies clearly prioritize reinforcement; Class D structures have overall failure of the load-bearing components, constituting entire dangerous houses, and should be demolished as much as possible.

Determining Whether a House Has Prefabricated Panels

1. Observe the floor slab structure: Prefabricated panels usually appear as regular blocks with obvious gaps between panels; cast-in-place slabs are flat without joint marks.
2. Check the construction year of the house: Houses built earlier are more likely to use prefabricated panel structures, while newly built houses in recent years generally use cast-in-place concrete structures.
3. Tap the floor slab to listen to the sound: Gently tap the floor slab with a hard object. If the sound is clear and the echo is long, it may be a prefabricated panel; if the sound is dull, it may be a cast-in-place slab.
4. Examine the house design drawings: If there are design drawings of the house, you can check the structural type of the floor slab to determine whether the house has prefabricated panels.