Is Prefabricated Panel Structure Housing Safe?

Prefabricated panel structure housing is not safe and has multiple safety hazards.

Insufficient seismic performance: Prefabricated panel houses mainly rely on cement for construction. Although a certain amount of steel bars are added, their overall seismic capacity is far inferior to that of modern buildings. Their integrity is poor, similar to building a house with building blocks. In an earthquake, the floor slabs and walls are prone to instant separation, and they often collapse suddenly without any crack warnings or deformation buffers, leaving few opportunities for escape. In past earthquakes, prefabricated panel houses have suffered severe collapses and high casualty rates.

Low structural strength of the house: Prefabricated panel houses are assembled from individual prefabricated panels, inherently lacking in robustness and toughness. They often adopt a hollow design, and the quantity and distribution of steel bars are not as scientific and reasonable as those in cast-in-place houses, akin to installing a fragile skeleton for the house. Even slight vibrations can loosen the joints between floor slabs, leading to an increase in cracks over time and even the collapse of the entire house. In addition, improper decoration can also easily trigger safety hazards.

Extremely fragile connection points: There is only simple overlapping between the prefabricated panels and the walls, and simple filling between the panels themselves, without ring beams or structural columns, resulting in the entire house lacking a rigid skeleton. When the foundation settles or the walls crack, the panels will become misaligned and loose. Over time, the connection points will weather and the steel bars will rust, reducing their strength. After living in such a house for twenty to thirty years, the floor slabs will become precarious, and even a slight increase in weight or knocking down a wall can trigger a chain collapse.

Frequent use of shoddy materials: The steel bars in regular prefabricated panels are thin, but small workshops, in order to make more profit, often use thin steel wires instead of steel bars, and the concrete grades do not meet the standards and the thickness is insufficient. Such prefabricated panels are brittle and prone to fracture, and will break instantly if overloaded without any warning. Daily activities such as stacking heavy objects, knocking on the ground during decoration, and aging over time can all lead to sudden collapses.

Short service life: The designed service life of prefabricated panel houses is about 30 to 50 years. Most of them were built in the 1970s to 1980s, and many have approached or exceeded their intended service lives, showing signs of aging. Many older prefabricated panel houses have been identified as 'dilapidated houses', which are difficult and costly to repair.