House Renovation with Prefabricated Slab Structure

When renovating a house with a prefabricated slab structure, it is essential to strictly adhere to structural safety principles, addressing renovation restrictions, reinforcement measures, functional optimization, and construction specifications comprehensively.

1. Structural Characteristics and Renovation Restrictions

Prefabricated slab buildings are primarily brick-concrete structures, featuring prefabricated concrete slabs for floors and load-bearing brick walls. The overall rigidity is relatively low. Their floor plans are constrained by the dimensions of the prefabricated slabs (typically with a span of 3-4 meters), resulting in fixed layouts with poor north-south ventilation and ceiling heights mostly between 2.6-2.8 meters. It is strictly prohibited to damage load-bearing structures during renovation, such as arbitrarily removing walls or floor slabs, as this can lead to a decrease in overall stability and even the risk of collapse. Additionally, the joints between prefabricated slabs (with a joint width of 50-110mm) require special reinforcement to prevent structural safety issues caused by joint cracking.

2. Reinforcement and Renovation Measures

If space reconfiguration is necessary, static cutting technology should be prioritized to minimize construction vibrations and avoid secondary damage to the prefabricated slabs. To address issues of insufficient structural stability, reinforcement can be achieved through the following methods:

• Carbon Fiber Reinforcement: Adhere carbon fiber sheets to the surface of the prefabricated slabs to enhance tensile strength;
• Joint Reinforcement with Rebar: Insert rebar into areas where the joint width exceeds standards to strengthen joint load-bearing capacity;
• Addition of Structural Columns: Install concrete structural columns at key load-bearing positions to improve overall rigidity.
  Before renovation, it is mandatory to confirm the original structural drawings and commission a professional agency to assess the building's safety, ensuring compliance with construction norms.

3. Functional Optimization Solutions

Prefabricated slab houses commonly suffer from poor sound insulation and thermal insulation, which can be improved through the following methods:

• Sound Insulation Treatment: Install sound insulation felt or acoustic cotton on walls or floor slabs, or lay cork flooring;
• Thermal Insulation Upgrade: Add an insulation layer to exterior walls (e.g., polystyrene boards), lay reflective thermal insulation film on roofs, or replace windows and doors with double-glazed units;
• Moisture Prevention Measures: Lay moisture-proof film on floors and apply waterproof coating to walls to prevent corrosion of internal rebar in the prefabricated slabs due to moisture.

4. Construction Precautions

Prefabricated slab buildings have relatively weak integrity, and the following behaviors should be avoided during renovation:

• Concentrated Stacking of Heavy Objects: Large furniture or building materials should be placed分散 (evenly distributed) to prevent floor slab cracking due to excessive local loads;
• Unauthorized Trenching for Wiring: Trenching should avoid joints between prefabricated slabs, with a depth not exceeding 1/3 of the slab thickness (usually ≤50mm) to prevent damage to internal rebar;
• Unauthorized Alteration of Pipelines: Water and electricity renovations must strictly follow the original design paths to avoid damaging load-bearing structures.

Special Reminder: Most existing prefabricated slab houses were built before the 1980s, with a service life of approximately 30-50 years. Some have already reached the standard for dilapidated buildings. Since 2022, China has implemented policies for old building renovations, focusing on repairs and upgrades, with demolition only for dilapidated buildings. If the house is old or poses significant safety hazards, it is advisable to prioritize complete reconstruction or reinforcement before use.