Can Prefabricated Housing Be Prefabricated On-Site?
Prefabricated housing is generally not prefabricated on-site. Instead, it adopts a construction method involving factory-prefabricated modules and on-site hoisting and assembly. This construction model combines the advantages of industrial production with the flexibility of on-site construction. The specific processes and characteristics are as follows:
Factory-prefabricated modules are the core link
Structural modules such as walls, floors, and stairs of prefabricated housing are all prefabricated in the factory. The factory has a standardized production environment and can achieve precise processing of modules through automated equipment, ensuring that key parameters such as dimensions and strength meet design requirements. For example, when Building No. 19 in Kaiyangli District 3, Fengtai District, Beijing, was constructed using "low- and multi-story steel-concrete composite modules", all modules were prefabricated in the factory, including the composite structure of the steel frame and concrete floor, as well as the pre-embedding of internal pipelines and insulation layers. Factory prefabrication can also reduce material waste through mass production and improve resource utilization.
On-site hoisting and assembly are key steps
After quality inspection, the prefabricated modules are transported to the construction site by special transport vehicles and positioned and hoisted using equipment such as cranes. The modules are structurally fixed through methods such as bolt connection, welding, or wet operations (such as concrete pouring) to form an integral building. For example, after the modules of Building No. 19 in Kaiyangli District 3 were hoisted, the steel frames of adjacent modules were connected with high-strength bolts, and then concrete was poured to form the integrity of the floors and walls. This assembly method reduces the amount of on-site wet operations and significantly shortens the construction period.
Significant advantages of industrial construction
The combination of factory prefabrication and on-site hoisting effectively solves the pain points of traditional on-site construction. On the one hand, the factory environment is controllable, which can avoid the impact of weather and site conditions on construction and ensure stable module quality. On the other hand, on-site construction only requires hoisting and a small amount of connection operations, reducing procedures such as scaffolding erection and formwork support and lowering environmental pollution such as noise and dust. Taking Building No. 19 in Kaiyangli District 3 as an example, its construction period was shortened by about 30% compared with traditional methods, and the on-site construction noise was controlled below 65 decibels, and the dust concentration was reduced by more than 50%.
Applicable scenarios and limitations
This model is suitable for multi-story and lower buildings, especially projects with high requirements for construction period and environmental protection (such as affordable housing and temporary buildings). However, for high-rise buildings or complex structures, due to the increased weight of modules, transportation limitations, and the difficulty of designing connection nodes, it is necessary to combine other technologies (such as slip-form construction) for comprehensive application.
