Grades of Prefabricated Panel Houses
The grades of prefabricated panel houses are classified into four levels (A, B, C, and D) according to the 'Standard for Dangerous Building Appraisal' (JGJ 125 - 2016).
Grade A: Houses of this grade have no dangerous components. The structure meets safety requirements for use, and all functions are normal, requiring only routine maintenance. For example, the main structure of the house is sound, the walls may just be a bit dirty, and there may be some slight marks at the joints of the prefabricated panels, but there are no cracks, water seepage, or deformation. Such houses are in good overall condition, and occupants can use them with peace of mind. They only need to be maintained according to normal house maintenance procedures, such as regularly cleaning the walls and checking the joints of the prefabricated panels to keep the house in good condition.
Grade B: Houses of this grade have individual components that are dangerous, but this does not affect the safety of the main structure, and the usage functions are basically intact. Common situations include fine cracks in non-load-bearing walls, which may be caused by factors such as natural settlement of the house or temperature changes, and generally do not pose a threat to the overall safety of the house; occasional water seepage at the joints of the prefabricated panels, which may be due to inadequate waterproofing or aging of the sealing materials at the joints; and slight sagging of the floor slab that is not visible to the naked eye, indicating that the load-bearing capacity of the floor slab is still within the normal range, but its changes need to be monitored. For Grade B houses, timely repair and reinforcement of the dangerous individual components are required to prevent the problem from worsening.
Grade C: Some load-bearing structures do not meet safety requirements for use, and parts of the house are in a dangerous state. Such houses have insufficient local load-bearing capacity, and relevant standards should be followed before reinforcement. For example, cracks or deformation in certain load-bearing columns, or obvious fractures in the prefabricated panels, may make the local load-bearing structures of the house unable to withstand normal loads, posing safety hazards. For Grade C houses, professional appraisal and assessment must be carried out, a reasonable reinforcement plan must be formulated, and reinforcement must be carried out in a timely manner to ensure the safe use of the house.
Grade D: The load-bearing structure no longer meets safety requirements for use, and the entire house is in a dangerous state. Only houses with serious overall load-bearing problems may be subject to demolition, reconstruction, expropriation, or in-situ reconstruction. For example, large-scale collapse of the load-bearing walls of the house, serious fractures in the prefabricated panels that cannot be repaired, etc., all indicate that the load-bearing structure of the house has been severely damaged and can no longer be used safely. Measures such as demolition or reconstruction must be taken to eliminate safety hazards.
