Extension of Prefabricated Panel Houses

Extending prefabricated panel houses requires careful handling due to potential safety hazards and specific conditions that must be met. It is recommended to prioritize repair and reinforcement to enhance safety and strictly adhere to policy requirements.

I. Structural Safety Risks

Prefabricated panel houses consist of independent panels, which are prone to issues such as joint cracking and deflection deformation after long-term use, resulting in poor overall integrity. If the original house lacks ring beams and structural columns (especially for brick-concrete structures of three stories or more), its seismic resistance and load-bearing capacity will be significantly reduced. Adding floors may further exacerbate structural instability and even lead to collapse risks.

II. Prerequisites for Adding Floors

1. Support Structure Reinforcement: It is necessary to entrust a professional institution to assess the load-bearing capacity of the original walls and beams. If necessary, additional columns and cantilever beams should be installed to ensure that the new loads can be effectively dispersed.
2. Connection Treatment: When adding floors, use an electric pick to chisel open the wall above the prefabricated panels (12 cm wide and 10 cm high) to allow the newly added reinforced concrete to be embedded in the wall, forming a reliable connection and preventing disconnection between the old and new structures.
3. Professional Appraisal: According to the "15th Five-Year Plan for Urban Renewal", a house safety appraisal must be conducted before adding floors. If the house is appraised as Class C (partially dilapidated) or Class D (completely dilapidated), priority should be given to repair and reinforcement rather than direct floor addition.

III. Risks of Unauthorized Renovation

Unauthorized addition of floors, installation of mezzanines, or stacking of heavy objects (such as large water tanks) may lead to overloading of the floor and trigger safety accidents. If the original house has undergone modifications such as the removal of load-bearing walls or changes in use (e.g., residential to commercial), the original structure must be restored and reappraised. Otherwise, the act of adding floors may be deemed illegal construction.

IV. Policies and Disposal Paths

1. Renovation Priority: Houses appraised as Class A or B can enhance safety through old residential area renovations (such as roof repairs and pipeline updates) rather than direct floor addition.
2. Government Subsidies: The central budget supports the renovation of Class C and D dilapidated houses, with subsidies not exceeding 70% of the total project investment. However, these subsidies are based on professional appraisal results.

Recommendation: Before adding floors to a prefabricated panel house, be sure to entrust a professional institution to assess the structural safety. Prioritize repair and reinforcement to enhance load-bearing capacity. If the appraisal results are not satisfactory, avoid adding floors and instead apply for government subsidies for renovation or demolition to ensure居住 safety (living safety) and compliance.