Shanghai Prefabricated Slab Houses
Shanghai's prefabricated slab houses have structural issues, hidden dangers from extended service, renovation cases, and diverse housing styles.
Structural Characteristics and Issues: The roofs of prefabricated slab houses are composed of multiple prefabricated concrete slabs joined together, with natural gaps between the slabs, resulting in weak structural integrity. The slab joints are the primary channels for water infiltration, continuously opening and closing due to various factors, causing ordinary waterproofing to easily crack and delaminate. The underlying issues are scattered and complex, with severe hidden water migration, leading to various problems on the surface layer. Rainwater can freely flow, making local repairs ineffective. Seasonal temperature variations cause the prefabricated slabs to expand and contract, resulting in frequent dynamic displacement of the slab joints. Ordinary thin-layer waterproof coatings and non-standard membranes lack sufficient tensile and deformation resistance, easily cracking and failing in the short term, leading to high recurrence rates of leaks. The roof gutters are areas where water, dust, and fallen leaves accumulate, subject to long-term rainwater erosion and ultraviolet exposure, causing conventional waterproofing to age, powder, and peel off, making them weak points prone to leakage. Some prefabricated slab houses have a designed lifespan of 30 to 50 years, but many are now in extended service, with 80% experiencing leaks and 60% failing to meet seismic standards.
Renovation Cases: The roof waterproofing renovation of Room 1102, Building 72, Phase I, Zhonghuan Jiayuan, Wanli Subdistrict, Putuo District, addressed industry-wide issues. Shanghai Ruisheng Construction Engineering Co., Ltd. developed a systematic renovation plan, abandoning traditional superficial solutions and using Dongfang Yuhong's national standard genuine waterproofing materials. The project passed the completion acceptance and comes with a 5-year formal written warranty. The renovation project at 129, 131, and 133 Xiangyang South Road, Xuhui District, involved small-beam thin-slab houses with fragile structures and prominent safety hazards. On November 23, 2024, the project completed contract signing and clearance, and was included in the old urban renovation scope to improve residents' living conditions.
Housing Conditions: Shanghai has not officially released a list of prefabricated slab house communities. Some products can be customized on demand, with styles including fully welded, modern minimalist, light steel mobile houses, and modern designs. Load capacities range from 500kg, 600kg, to 1500kg, with assembly methods including hoisting and modular assembly.
