Prefabricated House Fire Rating Standard

The fire rating standard for prefabricated houses mainly refers to the relevant regulations on the fire ratings of building structures and concrete prefabricated panels, as detailed below:

Fire Rating Standard for Building Structures

In China, the fire rating of building structures is classified into five levels according to the 'Technical Code for Building Fire Protection' and the 'Code for Fire Protection Design of Buildings' (GB 50016—2014):

• Level 1 Fire Protection: Buildings use inorganic materials both internally and externally, without employing combustible materials, offering the highest fire protection performance.
• Level 2 Fire Protection: Buildings should use fire-resistant materials as much as possible and avoid using flammable materials, suitable for places with high fire protection requirements.
• Level 3 Fire Protection: The standard fire rating for ordinary buildings requires that internal and external walls, roofs, doors, windows, and decoration materials of the building all meet this level. Restrictions are placed on the use of combustible materials, and fire-extinguishing facilities are installed within the building.
• Level 4 Fire Protection: Applicable to high-rise buildings, special buildings, and places with flammable and explosive materials, etc. It requires that the fire protection performance of the building be higher than the Level 3 standard, with stricter restrictions on the use of combustible materials.
• Level 5 Fire Protection: For fire protection requirements related to explosives, flammable, and explosive materials, the fire rating should be higher than the Level 4 standard. The combustion performance of building materials must meet requirements, and strict fire protection measures must be taken both inside and outside the building.

Fire Rating Standard for Concrete Prefabricated Panels

The fire rating of concrete prefabricated panels is usually classified into three levels based on the fire resistance limit (in hours), according to the Chinese standard (GB 50016 - 2014):

• Level 1 Fire Resistance: Fire resistance limit ≥ 1.5 hours, such as an ordinary concrete prefabricated panel with a thickness of 100mm having a fire resistance limit of about 2 hours.
• Level 2 Fire Resistance: Fire resistance limit ≥ 1 hour, such as a concrete prefabricated panel with a thickness of 80mm suitable for non-load-bearing partitions and ceilings.
• Level 3 Fire Resistance: Fire resistance limit ≥ 0.5 hours, such as some thinner concrete prefabricated panels that may be suitable for places with lower fire protection requirements.

In addition, exposed joints of prefabricated reinforced concrete members should be protected with fire protection measures, and the fire resistance limit of the joints should not be lower than that of the corresponding members to ensure the fire safety of the overall structure.