House - Prefabricated Panel

Prefabricated panel houses are buildings constructed primarily using prefabricated panels. They originated in the early 20th century and were widely adopted in China during the 1970s and 1980s, but have gradually been replaced by modern buildings.

Definition and Origin of Prefabricated Panel Houses

Prefabricated panel houses are centered around factory-made cement components (prefabricated panels), which are assembled on-site to form the building structure. This form emerged in the early 20th century, primarily used for floor slabs and roof insulation layers. Most residential buildings constructed in China before 1985 adopted this structure, especially during the 1970s and 1980s when state-owned enterprises or units built a large number of prefabricated panel houses to rapidly address the housing needs of employees, making them an important form of welfare housing distribution.

Characteristics of Prefabricated Panel Houses

Advantages:

• High Construction Efficiency: Factory-made components shorten the on-site construction period and reduce costs, meeting the context of soaring housing demand at that time.
• Simple Structure: Prefabricated panels come in two types: solid and hollow. The hollow structure achieves lightweighting by reducing non-load-bearing concrete, facilitating transportation and installation.

Disadvantages:

• Weak Seismic Performance: Relying on cement and a small amount of steel bars, their overall seismic capacity is far lower than that of modern buildings, posing significant safety hazards during earthquakes or floods.
• Poor Living Experience: Insufficient sound insulation and thermal insulation result in stuffy summers and cold winters, with noticeable sound interference between neighbors.
• Limited Renovation Options: The strong association between walls and the overall structure makes it difficult to carry out large-scale spatial adjustments or personalized renovations.
• Aging Issues: With a designed lifespan of about 30-50 years, most houses built in the 1970s and 1980s have approached or exceeded their service lives, presenting risks such as wall cracking, pipeline aging, and water leakage.

Policies and Development Directions

• Restrictions on New Construction: According to the Building Energy Efficiency Regulations, new projects are prohibited from using prefabricated panel structures.
• Renovation-Oriented Approach: Since 2022, renovation policies have been implemented, focusing on repairing and renovating prefabricated panel houses, with only buildings identified as Grade D dangerous houses being demolished.
• Priority for Demolition of Three Types of Houses:
  • Structural Damage: Such as dangerous houses with foundation settlement exceeding 5 cm or cracks in load-bearing walls exceeding 1 mm.
  • Insufficient Disaster Resistance: Houses with seismic ratings 70% below current standards or poor flood resistance.
  • Impact on Urban Planning: Houses located in municipal engineering planning areas or commercial development sites.
• Compensation Methods: Including monetary compensation (not less than 110% of the market price), physical resettlement, housing voucher resettlement (with rewards of 5%-12% in some areas), and original-site reconstruction (temporary relocation for 2 years followed by return, with the option to pay for expansion).

Current Situation and Future

With the popularization of cast-in-place concrete and prefabricated buildings (such as CMC combined modular buildings), prefabricated panel houses are gradually being replaced by safer and more comfortable modern buildings. Existing houses have become key targets for urban renewal and will gradually be phased out through demolition or renovation in the future.