Prefabricated Panels in Previous Rural Houses

The prefabricated panels used in rural houses in the past were mainly factory-prefabricated cement components, which had certain advantages but also serious problems and are now gradually being replaced.

Production and Types of Prefabricated Panels

They are formed by nailing wooden boards to create molds, arranging steel bars, and pouring cement. There are two types: solid and hollow. The hollow structure achieves lightweighting by reducing the non-load-bearing concrete.

Advantages of Prefabricated Panels

• Low Cost: They consume less steel, resulting in lower costs compared to traditional construction, which aligns with the economic conditions of farmers at that time.
• Simple Construction: The construction process is simpler than that of traditional buildings, with significantly shorter construction periods, enabling faster completion of house construction and meeting farmers' needs for prompt occupancy.
• Wide Application: In rural areas, they are commonly used for the roofs of the first floor, partitions between floors, or as floor slabs and roof panels. When reasonably used in buildings with regular structures and a small number of floors, they can ensure basic safety performance.

Problems with Prefabricated Panels

• Poor Structural Safety: They have poor integrity and almost zero earthquake resistance, making them prone to collapse directly during earthquakes. The connection points are fragile, with simple connections between the prefabricated panels and walls, as well as between panels themselves, lacking a rigid framework. When the foundation settles or the walls crack, the panels will shift and loosen. There is also a high incidence of shoddy materials, with high brittleness and susceptibility to fracture. Prefabricated panels produced by small workshops often have thin steel bars, substandard concrete grades, and insufficient thickness, and can break instantly when overloaded.
• Poor Sound Insulation: The thickness of prefabricated panels is usually around 10 centimeters, with long circular holes in the middle. Sound has strong penetrating power, and the structure itself easily transmits sound. Noise from neighboring rooms can even be amplified after passing through the holes.
• Serious Water Leakage: There are tiny gaps between the panels, and during the rainy season, rainwater can easily seep through these gaps into the interior of the prefabricated panels, corroding the steel bars inside.

Current Status of Prefabricated Panels

With the development of construction technology, cast-in-place concrete and prefabricated buildings are gradually replacing traditional prefabricated panel houses. Since 2022, China has implemented a policy of renovating old residential areas, focusing on repairing and renovating prefabricated panel houses and only demolishing buildings that meet the criteria for dangerous houses.