Houses Built with Prefabricated Panels
Houses built with prefabricated panels are structures primarily constructed using prefabricated panels, also known as prefab panel houses. They are characterized by low construction costs and short construction periods, but they also suffer from poor overall integrity and weak earthquake resistance. The current approach to handling these houses follows the principle of 'adapting measures to local conditions and implementing strategies based on classification'.
Definition and Origin of Prefab Panel Houses
Prefab panel houses are structures primarily built using factory-prefabricated cement components (prefabricated panels). These panels are formed by nailing wooden models, arranging steel bars, and pouring cement, and they come in two types: solid and hollow. This architectural form originated in the early 20th century. In China, residential buildings constructed before 1985 often adopted this structure, primarily built in the 1970s and 1980s. They were funded by state-owned enterprises, government agencies, and institutions to address the housing needs of their employees.
Characteristics of Prefab Panel Houses
- Advantages: Low construction costs and short construction periods, enabling rapid and cost-effective housing solutions to meet immediate residential demands.
- Disadvantages:
- Poor Overall Integrity: The connection between prefabricated panels and beams is hinged, resulting in generally poor waterproofing, sound insulation, thermal insulation, and earthquake resistance. The earthquake resistance level is typically lower than that of cast-in-place structures.
- Weak Earthquake Resistance: The structure, composed of cement components spliced together, is difficult to withstand the impact of natural disasters such as earthquakes.
- Poor Waterproofing and Seepage Resistance: Components are prone to cracking, and spliced gaps can easily lead to water leakage.
- Inadequate Sound Insulation and Thermal Insulation: The thin walls offer almost no sound insulation, making the houses hot in summer and cold in winter.
- Short Service Life: Generally ranging from 30 to 50 years, far shorter than modern commercial housing. Prefab panel houses that exceed their service life are prone to structural aging and are classified as dilapidated buildings requiring demolition or reinforcement.
- Difficult Structural Modifications: Load-bearing walls cannot be removed, and the housing design lacks humanization, such as kitchens or bathrooms potentially lacking windows.
Disposal and Renovation of Prefab Panel Houses
With the development of construction technology, cast-in-place concrete and prefabricated buildings are gradually replacing traditional prefab panel houses. In 2023, relevant Chinese authorities stipulated that the construction, renovation, and expansion of prefab panel houses and other buildings that do not comply with current standards are prohibited within urban construction land areas. Since 2022, China has implemented a policy of renovating old residential areas, focusing on repairing and renovating prefab panel houses and only demolishing those that meet the criteria for dilapidated buildings. The current approach to handling prefab panel houses follows the principle of 'adapting measures to local conditions and implementing strategies based on classification', rather than a comprehensive demolition. Priority for demolition is given to prefab panel houses with damaged main structures, inability to withstand natural disasters, impact on municipal planning, and those located in prime urban areas. Demolition compensation and resettlement follow the 'Regulations on the Expropriation of Houses on State-owned Land and Compensation', with resettlement methods primarily including monetary compensation, physical resettlement, housing vouchers, and original-site reconstruction. Reinforcement methods include the enlarged cross-section reinforcement method (pouring a reinforced concrete overlay with a thickness of ≥40mm on the panel surface or bottom) and the steel plate bonding method.
