Quality Requirements for Prefabricated Housing Products
The quality requirements for prefabricated housing products cover multiple aspects, including compliance with standards, usability, quality inspection systems, structural safety, seismic performance, sound and thermal insulation, service life, and fire safety regulations.
Compliance with Standards: According to the Product Quality Law of the People's Republic of China, as a product, prefabricated houses must meet national and industry standards that safeguard human health and personal and property safety. The production process must strictly adhere to relevant standards to eliminate unreasonable risks that could endanger personal and property safety.
Usability: Prefabricated houses should possess the necessary usability, encompassing structural safety, living comfort, and the integrity of equipment and facilities. If there are any usability defects, producers are obligated to provide explanations.
Quality Inspection System: Construction units must inspect building materials, building components, equipment, and commercial concrete in accordance with engineering design requirements, construction technical standards, and contractual agreements. The production of prefabricated houses requires the establishment and improvement of a construction quality inspection system, with strict process management to ensure quality compliance at all stages. Additionally, the Regulations on the Supervision and Management of the Quality of Housing Construction and Municipal Infrastructure Projects clarify the procedures for engineering quality supervision and management to safeguard the quality of prefabricated houses.
Structural Safety: Prefabricated components must meet stringent load standards. For example, the design live load for typical residential prefabricated floor slabs should be no less than 200 kilograms per square meter, with dead loads including the self-weight of the slab and the weight of the finishing layer. Ordinary prefabricated slabs are suitable for spans of 3 to 6 meters; spans exceeding this require special structural calculations and reinforced construction. In actual projects, the resting length of prefabricated components should be no less than 10 centimeters, and effective connections at supports must be ensured.
Seismic Performance: According to the Code for Seismic Design of Buildings, prefabricated structures must pass integrity checks, with node connection areas capable of withstanding repeated loads under design earthquake conditions. Additionally, energy dissipation devices or redundant restraint systems must be installed.
Sound and Thermal Insulation: The airborne sound insulation level of separating walls should be no less than 50 decibels, and the impact sound pressure level of floor slabs should be controlled below 65 decibels. In actual projects, elastic cushions or floating floor structures are often used to meet these standards.
Service Life: The design service life of prefabricated residential buildings in ordinary climatic zones is 50 years, but structural inspections are required every 10 years. In coastal areas with high salt spray or northern regions with frequent freeze-thaw cycles, this standard is shortened by 20 to 30 percent. The newly revised Residential Project Specifications in 2024 incorporate the thickness of anti-corrosion coatings for prefabricated components as a mandatory provision, stipulating that the minimum protective layer thickness in exposed environments should be no less than 30 millimeters.
Fire Safety Regulations: The fire resistance limits for prefabricated concrete components are 3 hours for load-bearing walls, 2 hours for non-load-bearing walls, and 1.5 hours for floor slabs. Steel-structured prefabricated houses must be protected with fire-resistant coatings or fire-resistant panels, and additional fire barriers must be installed in high-risk fire areas such as prefabricated kitchens and bathrooms.
