Evaluation Grades of Prefabricated Panel Houses

The evaluation grades of prefabricated panel houses are divided into four grades, A, B, C, and D, according to relevant standards. The specific classification criteria and data distribution are as follows:

According to the 'Building Safety Appraisal Standard' or the 'Technical Guidelines for the Appraisal of Dangerous Rural Houses (Trial)', the evaluation grades of prefabricated panel houses are mainly determined based on structural safety, the condition of load-bearing components, and overall stability.
Grade A: The structure fully meets the requirements for safe use, with no dangerous points in the load-bearing components, and the house is generally safe. Such houses do not require reinforcement or repair and can be used normally. For example, there are no cracks or deformations in the structural components, the foundation is stable, and there are no signs of settlement.
Grade B: Some load-bearing components are in a dangerous state (such as minor local cracks or steel reinforcement corrosion), but this does not affect the safety of the main structure and generally meets the requirements for normal use. Monitoring or local repairs of the dangerous components are required. For example, fine cracks appear in the walls but do not penetrate, and there is slight flaking on the surfaces of beams and columns.
Grade C: Some load-bearing structures do not meet safety requirements, and local hazards have occurred, constituting a partially dangerous house. Typical manifestations include large cracks in the walls (width exceeding 5mm), obvious cracks or deformations in beams and columns, and insufficient load-bearing capacity of the floor. Such houses require immediate reinforcement measures, such as pasting carbon fiber sheets or adding support structures; otherwise, they may develop into fully dangerous houses.
Grade D: The load-bearing structure has completely failed, constituting a fully dangerous house. This is manifested by severe uneven settlement of the foundation (such as the house tilting more than 1%), serious cracks in most load-bearing walls (cracks that penetrate and are wide), large-scale flaking of concrete on beams and columns, or exposed and corroded steel reinforcement. Such houses have no repair value and need to be demolished and rebuilt.

Data distribution shows that the overall safety of prefabricated panel houses is relatively high: According to the national survey data on building construction and municipal facilities, among the prefabricated panel buildings that have completed safety evaluations, approximately 72% are rated as Grade A or B (with Grade A accounting for about 50% and Grade B about 22%), about 25% are rated as Grade C, and only a very small number (about 3%) are rated as Grade D, which truly requires demolition. This distribution indicates that most prefabricated panel houses have a safe structure, and only a few have local hazards due to age, design defects, or improper maintenance.

The determination of evaluation grades must be carried out by professional institutions through comprehensive analysis, including on-site inspections and structural calculations. Individuals should not make subjective judgments based solely on appearance. If abnormal phenomena such as cracks or deformations occur in the house, it is recommended to promptly contact the local housing and urban-rural development department or a professional appraisal institution for inspection.