Prefabricated Slab Roofing for Buildings

The application situations and characteristics of prefabricated slab roofing for buildings in urban and rural areas are as follows:

Renovation of prefabricated slab houses in urban areas

• Renovation background and policies: From the 1970s to the early 1990s, a large number of urban houses adopted prefabricated slab structures, which had problems such as water leakage, poor sound insulation, low earthquake resistance, and wall cracking. Nowadays, eligible dilapidated and old prefabricated slab houses can be included in the scope of original-site demolition and reconstruction. The '15th Five-Year Plan for Urban Renewal' issued by the State Council proposes to renovate more than 500,000 sets (rooms) of prefabricated slab houses on state-owned land within the built-up areas of cities and county towns, basically eliminate the safety hazards of registered D-grade dangerous houses, and list prefabricated slab houses as an independent renovation category. The Ministry of Housing and Urban-Rural Development supports the self-initiated renewal and original-site demolition and reconstruction of old houses.
• Renovation cases: Building 28 in Sanlihe Area 1, Xicheng District, Beijing, was built in 1978 and started demolition in September 2025. It adopted factory-prefabricated module units, which were transported to the site for hoisting and assembly. The roof was capped in 45 days, and the building was delivered in February 2026. Previously, this building was identified as a D-grade dilapidated house, and residents had long suffered from problems such as blocked and rusted water supply and drainage pipelines, no exterior wall insulation leading to substandard heating in winter, and wind-eroded and cracked balconies. Hongyuan Community in Yueqing, Wenzhou, Zhejiang, was built in 1986 and identified as a C-grade dilapidated house in 2015. It was upgraded to a D-grade dilapidated house in 2025. After the implementation of relevant policies from 2024 to 2025, it was listed as a pilot project for self-initiated renewal, and the project is expected to be completed in June 2027. Changcheng Jiaoyuan Community in Yuecheng District, Shaoxing, was built in the early 1990s. The first round of willingness surveys started in June 2025, and on July 23, 2026, all 273 households signed up within 12 days.

Use of prefabricated slabs for roofing in rural self-built houses

• Reasons for application: In rural self-built houses, prefabricated cement slabs were basically used for roof covering before 20 years ago, mainly because of their low price and fast construction speed. Hoisting and installation could be completed in one day or half a day.
• Existing problems: There is a high probability of water leakage when doing waterproofing, and the earthquake resistance coefficient is low, so they cannot be used in earthquake-prone areas. The thermal insulation performance is also poor. For example, in a rural self-built house, the west side wing room used floor slabs (cement prefabricated slabs) with a total area of 40 - 50 square meters and a total cost of more than 800 yuan. The seller of the floor slabs was responsible for hoisting, but waterproofing needed to be done independently, and there was water leakage. In contrast, the east side wing room used a cast-in-place cement roof. The cost of formwork support alone exceeded 1,000 yuan, and with the addition of material and labor costs, the total cost exceeded 3,000 yuan.