Prefabricated Concrete Panels for Housing

Prefabricated concrete panels for housing, also known as prefabricated slabs, are concrete components produced and shaped in prefabrication yards and directly used for on-site installation in construction projects. The following provides an introduction from aspects such as types, dimensions, application scenarios, advantages and disadvantages, and development trends:

Types and Structures
Prefabricated slabs come in two main types: solid and hollow. The hollow structure achieves lightweighting by reducing the non-load-bearing concrete, lowering material usage while ensuring load-bearing capacity. During production, a hollow mold is first made using wooden planks. Reinforcing bars are placed inside the mold, and then concrete is poured. After drying, the wooden planks are knocked off to obtain the finished product.

Dimensions and Specifications

• Span: The longest prefabricated slabs for residential use are 4.2 meters; those exceeding this length require customization. The main widths are 500mm and 600mm, and common thicknesses are 120mm and 150mm.
• Load Ratings: They are classified into Grade I (1kN/m²), Grade II (2kN/m²), with the minimum in the southwest region specified as Grade IV (4kN/m²).
• Length: Designed in 300mm modules (e.g., 3000mm, 3300mm, etc.), with the longest ordinary slab being 4200mm.

Application Scenarios
Prefabricated slabs were once widely used for floor slabs, roof insulation layers, and highway ditch covers. Before 1985, most residential buildings in China adopted this structure, and some southern regions still use it for house construction today. During construction, they are laid from one end according to layout drawings, with strict regulations on slab joint widths: less than 30mm is unqualified, 30-50mm is acceptable, and 50-110mm requires reinforcement. Additionally, modern prefabricated movable concrete panel houses use materials such as concrete and color-coated steel, featuring snow and load-bearing capacities (e.g., 100kg/m², 1000kg/m²). They can be designed as light steel movable houses, mobile, or assembled types.

Advantages and Disadvantages

• Advantages: They shorten construction periods and reduce costs, suitable for rapid construction needs.
• Disadvantages: They have weak earthquake resistance, poor sound and thermal insulation, and a service life of approximately 30-50 years.

Development Trends
With advancements in construction technology, cast-in-place concrete and prefabricated buildings (e.g., CMC composite modular buildings enhance earthquake resistance through integrated steel-concrete pouring, reducing construction periods by 30%) have gradually replaced traditional prefabricated slab houses. Since 2022, China has implemented renovation policies for old residential areas, focusing on repairing and renovating prefabricated slab houses and only demolishing those that meet the criteria for dangerous buildings. In the global market, by April 2026, enterprises in the Guangzhou Customs area exported movable houses worth 1.4 billion yuan (a 38.1% year-on-year increase), and exports through the Shenzhen port reached 1.68 billion yuan (a 19.6% year-on-year increase), indicating sustained growth in demand for prefabricated buildings.