Prefabricated Beam-Slab House

Prefabricated beam-slab houses are a type of prefabricated assembled building, typically designed with a service life of 50 years. Whether they should be demolished depends on professional safety assessment results, and they will be included in urban renewal governance starting from 2026.

Structural Types and Technical Characteristics

Prefabricated beam-slab houses encompass two main types: prefabricated concrete structures and steel structures. Among them, panel-assembled buildings use prefabricated wall panels and floor slabs as core components, but their design flexibility is limited. Box-assembled buildings are formed by combining prefabricated functional units (such as kitchens and bathrooms), which can increase construction speed by 50%-70%, but they have higher requirements for transportation and lifting equipment. Their technical advantages include shortened construction periods and reduced on-site pollution. However, their overall stiffness is generally weaker than that of fully cast-in-place structures, especially during earthquakes or uneven foundation settlement, when cracks and deformations are prone to occur at panel joints, connections, and load-bearing walls.

Common Issues and Maintenance Requirements

Some prefabricated slab houses built in the 1980s and 1990s commonly suffer from issues such as roof leakage, fine wall cracks, and poor sound insulation due to incomplete installation of ring beams and structural columns. For example, a project in Nanjing once experienced rainwater leakage due to improper panel joint treatment, requiring regular maintenance such as updating the waterproof layer and repairing cracks to extend the service life. Additionally, the connection joints of prefabricated components (such as beam-slab joints) are structural weak points that require focused inspection and reinforcement.

Safety Assessment and Governance Policies

The safety of prefabricated slab houses is classified through professional assessments:

• Grade A: Can be used normally without treatment;
• Grade B: Requires local maintenance (such as repairing cracks);
• Grade C: Requires local reinforcement or reconstruction;
• Grade D: Is deemed a dangerous building and requires immediate demolition and reconstruction.

Starting from 2026, the governance of such houses will be included in urban renewal efforts, with treatment methods including safety inspections, reinforcement and reconstruction, original-site reconstruction, or expropriation and resettlement. The specific choice depends on the assessment results, planning conditions, financial capabilities, and resident consultations. For example, Grade D houses will be prioritized for demolition and reconstruction, while Grade C houses may undergo reinforcement and repair or be reconstructed in conjunction with urban planning.

Practical Application Cases

Enterprises such as Vanke Group have developed prefabricated shear wall residential structural systems and applied prefabricated frame technology in projects. For example, the Nanjing Jindi Yufang project adopted a prestressed prefabricated concrete assembled integral frame structural system, which improved component precision through industrial production and significantly enhanced on-site assembly efficiency. Such technological innovations have driven the development of prefabricated beam-slab houses toward higher safety and durability.