Prefabricated Houses and Precast Panels

Prefabricated houses are a form of modular construction, with precast panels being a common component. While the two show a trend of technological integration in their evolution, they differ in application scenarios and performance.

Definition, Classification, and Core Advantages of Prefabricated Houses

Prefabricated houses, also known as modular construction, involve breaking down a house into components such as wall panels, floor slabs, and stairs, which are prefabricated in factories and then transported to the site for assembly, similar to building with “LEGO blocks.” This construction method originated in the American colonial period in the 17th century and saw rapid development after World War II due to post-war reconstruction needs. Currently, there are five main categories:

• Block Construction: Built using prefabricated blocks (e.g., concrete or aerated blocks), suitable for low-rise residential buildings;
• Panel Construction: Assembled from large prefabricated wall panels and floor slabs, offering high construction efficiency;
• Box Construction: Entire rooms or functional modules are prefabricated and directly hoisted and combined on-site;
• Skeleton-Panel Construction: Uses a steel or concrete frame as the skeleton, with prefabricated panels attached externally;
• Lift-Slab Construction: Floor slabs are lifted to the designed height using hydraulic equipment, reducing high-altitude work.

The core advantages include:

1. Short Construction Period: For example, Wuhan Leishenshan Hospital was built in 10 days using modular construction techniques and put into operation;
2. Environmental Protection and Energy Efficiency: Factory prefabrication reduces on-site wet work, lowering dust and noise pollution while improving material utilization by over 30%;
3. Flexibility and Reusability: Components can be disassembled and reassembled, making them suitable for temporary buildings or emergency scenarios;
4. Lower Cost: In a case in Henan, the cost per square meter of a prefabricated house was about 300 yuan, with assembly completed in 4 hours and a lifespan of 70 years.

Definition, Types, and Historical Applications of Precast Panels

Precast panels are factory-made concrete components formed by nailing wooden molds, laying out steel reinforcement, and pouring concrete. They come in two types:

• Solid Precast Panels: Strong load-bearing capacity but heavy, commonly used in early low-rise buildings;
• Hollow Precast Panels: Lightweight by reducing non-load-bearing concrete, lowering transportation and installation costs.

Precast panel houses were the mainstream form of residential construction in China before 1985, but existing houses generally have three major issues:

1. Weak Earthquake Resistance: Node connections rely on cement mortar, making them prone to cracking and detachment during earthquakes;
2. Poor Sound and Thermal Insulation: Hollow structures lead to rapid heat conduction, requiring additional insulation layers;
3. Short Lifespan: Designed for a lifespan of about 30-50 years, far below modern construction standards.

Technological Integration and Future Trends

Currently, the application of prefabricated houses and precast panels shows a trend of technological integration:

• Continuation of Traditional Precast Panels: In rural self-built houses and other scenarios, precast panels are still widely used due to their low cost and fast construction, such as quickly assembling temporary housing by joining precast panels;
• Upgrading of Modular Construction: Adopting steel-concrete composite modules (e.g., CMC technology) to enhance earthquake resistance through integral pouring, reducing construction time by 30% compared to traditional methods;
• Global Market Recognition: Data from 2026 shows significant growth in China's prefabricated house exports (e.g., enterprises in the Guangzhou Customs district exported 1.4 billion yuan worth of mobile houses in the first four months, a year-on-year increase of 38.1%), reflecting the international competitiveness of industrialized construction methods.

In the future, with improvements in digital precision and automation efficiency, house construction will further shift from “on-site construction” to “factory manufacturing,” driving the development of prefabricated houses and precast panel technologies toward higher performance and broader applications.