Technical Specifications for the Application of Prefabricated Housing

The technical specifications for the application of prefabricated housing cover six core areas: fire safety, structural design, acceptance control, regional functionality, environmental protection and economy, and specific structural systems. The specific specifications are as follows:

I. Fire Safety and Material Usage Specifications

1. Fire Safety: If prefabricated housing uses flammable materials such as polystyrene and polyurethane foam, it must strictly comply with Article 54 of the Fire Protection Law of the People's Republic of China and promptly eliminate fire hazards; otherwise, it may face temporary closure.
2. Material Requirements: Flammable foam sandwich panels are prohibited in crowded places, and non-combustible or fire-resistant materials such as rock wool should be used instead. The concrete strength grade of prefabricated components must not be lower than C30 (with a requirement of C35 or higher for load-bearing wall panels). The diameter of the main reinforcement bars should be ≥8mm, with a spacing of ≤200mm, and the thickness of the protective layer should be ≥20mm (≥25mm in exposed environments).

II. Structural Design and Construction Specifications

1. Seismic Performance: In areas with a seismic fortification intensity of 6 degrees, the requirement of 'no damage under minor earthquakes' must be met, while areas with a seismic fortification intensity of 7 degrees or higher require special calculations. Node connections should use embedded part welding or high-strength bolts (with a tensile strength of ≥8.8 grade).
2. Dimensional Accuracy: The length error of wall panels should be ±3mm, and the thickness error should be ±2mm; the position deviation of door and window openings should be ≤5mm.
3. Construction Organization: It is necessary to follow the principle of integrating design, production, and assembly. The construction plan should cover component installation, node construction, quality management, and safety measures.

III. Acceptance and Quality Control Specifications

1. Factory Inspection: Each batch of components must undergo compression and impermeability tests, with a sampling ratio of ≥5% and an impermeability grade of ≥P6 (no leakage under 0.6MPa water pressure).
2. On-site Acceptance: The verticality deviation should be ≤h/1000 (where h is the wall height) and ≤10mm; the joint waterproofing should use elastic sealant with a width of ≥15mm and a peel strength of ≥0.5MPa.

IV. Regionalization and Functional Design Specifications

1. Regional Characteristics: It is necessary to combine local climate, topography, and traditional architectural features (such as reflecting regional characteristics in the Luzhong and Jiaodong regions). The floor plan should facilitate sunlight and ventilation, and a north-south orientation is preferable.
2. Age-friendly Design: The entrance should be equipped with barrier-free ramps, and functional spaces should include bedrooms, storage rooms, etc. The living space should be divided to achieve separation of dynamic and static areas.

V. Environmental Protection and Economic Specifications

1. Environmental Requirements: Wastewater discharge must comply with the Integrated Wastewater Discharge Standard (GB 8978-1996), with a pH value of 6-9 and suspended solids ≤70mg/L; priority should be given to selecting green, economical, or recyclable materials.
2. Lightweight Design: Some rural projects use hollow prefabricated panels with a void ratio of ≤30%, reducing self-weight by 20% and saving costs by approximately 15%.

VI. Specific Structural System Specifications

1. Prefabricated Concrete Shear Wall Structural System: It must comply with the Code for Seismic Design of Buildings (GB 50011-2010) and the Technical Standard for Prefabricated Concrete Buildings (GB/T 51231-2016).
2. EPS Module Cast-in-Place Concrete Structural System: The thermal conductivity of the exterior wall panel should be ≤0.24W/(m·k), and the sandwich panel commonly uses 50mm-thick polystyrene foam (EPS) or rock wool layers.