National Standard Size Specifications for Prefabricated Houses

There is no directly unified and explicitly defined national standard size for prefabricated houses, but specific norms exist for the sizes of related components (such as prefabricated concrete houses and prefabricated floor slabs), which can serve as design references. The following provides an explanation from the perspectives of prefabricated concrete houses and prefabricated floor slabs:

I. Size Specifications for Prefabricated Concrete Houses Prefabricated concrete houses typically adopt a modular design, with standard sizes mainly based on common specifications while also supporting customized adjustments.

1. Standard Module Sizes: Common specifications include 3m × 6m, 4m × 8m, and 5m × 10m, suitable for residential and temporary building scenarios. These sizes balance transportation convenience and space utilization, and can be combined and expanded to form larger buildings.
2. Customized Size Ranges:
   • Width: The basic range is from 3m to 4m (e.g., 3.1m, 3.2m). Special requirements can extend to 7.2m or 7.6m, depending on transportation conditions and structural stability design.
   • Length: It can be flexibly customized (e.g., 6.6m), adjusted according to site conditions and functional requirements.
   • Height and Number of Floors: Usually single-story or double-story structures, with heights complying with building safety regulations (e.g., floor height not less than 2.8m). Multi-story buildings require enhanced structural connections and seismic design.

II. Size Specifications for Prefabricated Floor Slabs As a key component of building structures, the sizes of prefabricated floor slabs need to meet load-bearing capacity and construction efficiency requirements, with specific norms as follows:

1. Thickness: Common specifications are 60mm, 80mm, 100mm, 120mm, and 150mm. Among them, residential buildings often use 80-100mm, while industrial buildings, due to larger loads, commonly use 120-150mm.
2. Width: Adopt a standard modular design, commonly 600mm, 900mm, and 1200mm. Some customized requirements can be extended to 2400mm, depending on the floor slab span and reinforcement design.
3. Length: The conventional span is from 2.4m to 6m (for residential buildings). Large-span factory buildings can reach 9m to 12m, requiring enhanced reinforcement or the use of prestressed technology to improve load-bearing capacity.

III. Supplementary Notes For complete national standard size specifications for prefabricated houses, further reference should be made to normative documents such as the Technical Standard for Prefabricated Concrete Buildings (GB/T 51231-2016) and the Quality Inspection Standard for Prefabricated Concrete Components (JGJ 1-2014). In actual design, size selection should comprehensively consider transportation limitations, structural safety, usage functions, and local regulatory requirements. It is recommended that professional design units formulate plans based on specific needs.