What Are Prefabricated Houses?

Prefabricated houses are a form of construction where building components are industrially produced and assembled on-site. The building is broken down into independent modules, prefabricated in factories, and then transported to the site for assembly, similar to building with 'building blocks'.

Core Production Process of Prefabricated Houses

Prefabricated houses divide the building into independent modules such as ceilings, floors, and water and electrical pipelines. All prefabrication processes, including structural connections, pipeline embedment, and decorative surface treatments, are completed in factories. For example, wall modules can integrate insulation layers, door and window frames, and exterior finishes. Water and electrical pipelines are embedded in factories with reserved interfaces. On-site, modules only need to be joined using bolts or welding, eliminating the need for traditional masonry or pouring processes.

Main Types and Historical Background

Prefabricated houses mainly fall into three categories:

1. Panel Assembly Type: Primarily using prefabricated wall panels and floor slabs, these components are assembled on-site to form the building's main structure, suitable for multi-story residential buildings;
2. Box Assembly Type: Entire rooms or functional units (such as bathrooms and kitchens) are prefabricated as 'boxes' and directly hoisted and assembled, commonly seen in hotels and apartments;
3. Frame Assembly Type: With a core of prefabricated concrete or steel structural frames, prefabricated floor slabs, wall panels, and other enclosure structures are installed on-site, mostly used in high-rise buildings.
   They originated in the mid-20th century to address post-war housing shortages. By borrowing foreign industrialized construction techniques, standardized prefabricated components replaced the slow on-site construction of bricks and mortar, significantly reducing costs and adapting to large-scale construction needs.

Advantages and Limitations Compared to Traditional Construction

Compared to traditional buildings, the modular form of prefabricated houses offers significant advantages:

• Shortened Construction Period: The construction cycle can be reduced by more than 60% as factory prefabrication and on-site construction proceed simultaneously, and on-site work volume is greatly reduced;
• Controllable Quality: The factory environment avoids weather interference, with component dimensional accuracy reaching the millimeter level, reducing common quality issues;
• Energy Efficiency and Environmental Protection: Material waste is reduced by more than 30%, and construction waste by 50%. Additionally, green technologies such as solar panels and ground-source heat pumps can be integrated;
• Convenient Maintenance: Modular design facilitates later pipeline maintenance or space renovation.
  However, they have extremely high requirements for industrial foundations, needing a complete technical system (such as BIM collaborative design), production system (such as automated production lines), and industrial clusters (such as supporting factories within a 50-kilometer radius for component transportation) for support. Otherwise, cost overruns may easily occur due to insufficient component accuracy or supply chain disruptions.