Houses Made of Cement Prefabricated Panels

Houses made of cement prefabricated panels are structures built primarily using prefabricated panels, which have issues such as relatively short service life, poor earthquake resistance, and easy ground water seepage. They are gradually being replaced by cast-in-place concrete and prefabricated buildings. Currently, the focus is on repair and renovation, with only dangerous buildings being demolished.

Characteristics and Origins

The prefabricated panels of cement prefabricated panel houses are cement components prefabricated in factories. During production, wooden models are nailed, steel bars are arranged, and cement is poured. There are two types: solid and hollow. The hollow structure achieves lightweighting by reducing the non-load-bearing concrete. This building form originated in the early 20th century and was mainly used for floor slabs and roof insulation layers. In China, most residential buildings built before 1985 adopted this structure. In rural areas, due to the low use of steel bars, low cost, and simple construction techniques, it could ensure sufficient safety in buildings with regular structures and a small number of floors, and was once very popular.

Existing Problems

• Service Life: The designed service life is generally relatively short, typically 30 - 40 years, while modern commercial housing can last 70 years or even longer. After decades of construction, many prefabricated panel houses experience aging of the main structure and failure of facilities. Problems such as cracking, deformation, and water leakage may occur in roofs and walls. Electrical wiring and pipeline systems are also prone to aging, and the consequences of accidents can be serious. However, without significant external factors, the normal service life is about 40 - 50 years.
• Earthquake Resistance: Most of them are assembled using cement components with insufficient steel bar reinforcement, resulting in low overall structural strength. In the face of natural disasters such as earthquakes, they are difficult to withstand strong vibrations and impacts and are prone to collapse or severe damage. The collapse of a large number of prefabricated panel buildings in the Wenchuan earthquake is an example.
• Ground Water Seepage: The building components are mainly poured with cement and lack steel bar reinforcement inside, making the ground prone to water seepage.
• Other Deficiencies: The prefabricated panels are assembled one by one, leaving gaps at the edges. Compared with cast-in-place slabs, they have many deficiencies.

Development Trends

With the development of building technology, cast-in-place concrete and prefabricated buildings are gradually replacing traditional prefabricated panel houses. Since 2022, China has implemented a policy of old building renovation, focusing on repair and renovation of prefabricated panel houses and only demolishing buildings that meet the criteria for dangerous buildings. Some regions have already started demolition work.