Standard Specifications for Prefabricated Panel Houses

The standard specifications for prefabricated panel houses cover the inspection of old urban houses, national regulations, renovation policies, and standards for rural self-built houses, as detailed below:

I. Safety Inspection Specifications for Old Urban Prefabricated Panel Houses

1. Structural Integrity and Foundation Inspection: Check for foundation settlement, house tilting, diagonal cracks at the base of walls, and differences in indoor and outdoor ground levels.
2. Special Inspection of Core Components:
   • Prefabricated Floor Slabs: Inspect for horizontal through-cracks at the bottom of the slabs, cracks in the joints, signs of sagging in the middle, and loose concrete or rusted steel bars at the ends where the slabs rest.
   • Load-Bearing Walls: Examine for vertical/diagonal cracks, cracking and deformation of door and window lintels, weathering and spalling at the base of ground-floor walls, and confirm the presence of ring beams and structural columns.
   • Node Connections: Check for loose supports of prefabricated panels and whether the corners/junctions of walls are detached or cracked.
3. Inspection for Unauthorized Renovations and Usage Environment: Verify whether load-bearing walls have been removed or altered, unauthorized additions have been made, or the usage has been changed (e.g., residential to commercial).

II. National Regulations on Prefabricated Panel Houses

1. Fire Safety: The use of flammable materials such as polystyrene and polyurethane foam is strictly prohibited. Compliance with the Fire Protection Law is required, and those with serious hazards will be temporarily sealed off.
2. Building Materials: Foam sandwich panels are prohibited in crowded places. Non-combustible or fire-resistant materials such as rock wool should be used instead.
3. Planning and Approval: Construction must comply with land use planning, and procedures for land use rights and building permits must be followed.

III. Renovation Policies for 2026

1. Renovation-Oriented Approach: Plans to renovate more than 500,000 sets of Grade C and D dilapidated houses and prefabricated panel houses, rather than full demolition.
2. Demolition-to-Construction Ratio Limit: The demolished area shall not exceed 20% of the current status, and the demolition-to-construction ratio shall not be greater than 2.
3. Basis for Appraisal Reports: According to the Standard for Appraisal of Dangerous Houses (JGJ 125-2016), Grade D dilapidated houses shall be demolished, and Grade C houses can be repaired and reinforced.

IV. Specifications for Prefabricated Panels in Rural Self-Built Houses

1. Material Selection: Prefabricated panels and auxiliary materials such as steel bars and cement must comply with national standards.
2. Structural Design: Calculate loads reasonably, determine spans and spacing, and use reliable connection methods such as welding and bolts.
3. Construction and Installation: The foundation must be level and solid. Install according to the design sequence, set up temporary supports, and secure them firmly.
4. Acceptance and Maintenance: After completion, inspect the quality and connections, and perform regular maintenance.