Monolithic Prefabricated Panel House

Monolithic prefabricated panel houses are structures primarily built using prefabricated panels, featuring a specific historical background, structural characteristics, and existing issues. Currently, the focus is on repair and renovation, with some requiring demolition and reconstruction.

Origin and Structural Characteristics

Monolithic prefabricated panel houses originated in the early 20th century, primarily used for floor slabs and roof insulation layers. The prefabricated panels are factory-made concrete components, created by nailing wooden molds, arranging steel bars, and pouring concrete. They come in two types: solid and hollow. The hollow design reduces the non-load-bearing concrete, achieving lightweight construction and improving building efficiency at the time. Most residential buildings constructed in China before 1985 adopted this structure, typically with no more than six floors. These houses were extensively built in the 1970s and 1980s due to their fast construction speed and low cost.

Existing Issues

Existing prefabricated panel houses generally face several problems. Weak earthquake resistance: During natural disasters like earthquakes, their structural stability is poor and they are prone to damage. Poor sound and heat insulation: They cannot effectively block external noise and heat transfer, affecting living comfort. Service life of about 30-50 years: The design life of most prefabricated panel houses is significantly shorter than the 80-100 years of modern reinforced concrete buildings. Over time, more than 35% of these houses have developed various safety hazards, including wall cracks, loose floor slabs, and steel bar corrosion, seriously threatening residents' lives and property.

Renovation Policies

With advancements in construction technology, cast-in-place concrete and prefabricated buildings are gradually replacing traditional prefabricated panel houses. Since 2022, China has implemented renovation policies focusing on repair and renovation of prefabricated panel houses, with demolition only for buildings that meet the criteria for dangerous structures. The renovation of prefabricated panel houses will adopt a "precision surgery" approach based on different conditions. For those with good structural safety but outdated functional facilities, methods such as reinforcement and functional upgrades will be used to extend their service life. For those with severe structural safety hazards that cannot be resolved through reinforcement and repair, demolition and reconstruction will be carried out.