Prefabrication Rate of Buildings

The prefabrication rate of buildings is a core indicator for measuring the industrialization level of prefabricated buildings, reflecting the comprehensive application proportion of prefabricated components in buildings. Its definition, calculation method, regional differences, and policy requirements are as follows:

1. Definition and Calculation Method The prefabrication rate refers to the comprehensive proportion of prefabricated components used in the main structure, enclosure walls and interior partitions, decoration, and equipment pipelines above the outdoor ground level of a single building. According to the "Evaluation Standard for Prefabricated Buildings" (GB/T 51129-2017) and the calculation rules revised in 2026 for Hainan Province, the prefabrication rate is calculated using the formula: $P = \frac{q_1 + q_2 + q_3 + q_t}{100 - q_4} \times 100%$ where:

• $q_1$ is the actual score for the main structure (e.g., the application proportion of prefabricated columns, beams, and floor slabs);
• $q_2$ is the actual score for the enclosure walls and interior partitions (e.g., the application proportion of prefabricated exterior wall panels and interior partition panels);
• $q_3$ is the actual score for decoration and equipment pipelines (e.g., the application proportion of integrated kitchens and separated pipeline technologies);
• $q_4$ is the total score of missing evaluation items (e.g., deducting corresponding scores when a certain technology is not adopted);
• $q_t$ is the additional score for other innovative items (e.g., the application of green building materials and intelligent technologies). This formula ensures calculation rationality by adjusting the denominator (deducting the scores of missing items) and reflects the industrialization level through the comprehensive scores of various dimensions in the numerator.

2. Regional Differences and Policy Requirements There are differences in the prefabrication rate requirements among different regions:

• Hainan Province clearly stipulates that the prefabrication rate of prefabricated buildings should be no less than 50%, applicable to eligible projects of newly-built public buildings, residential buildings, and industrial buildings;
• Shanghai has expanded the implementation scope of prefabricated buildings (e.g., including underground buildings in the evaluation) and increased the weight of decoration (e.g., the proportion of fully-decorated buildings and the application of integrated kitchens) by revising the calculation rules, promoting the development of building industrialization to a higher standard. The differences in regional policies reflect different focuses on building industrialization. For example, Hainan focuses on basic proportion requirements, while Shanghai pays more attention to technology integration and full-lifecycle management.

3. Practical Application Significance The prefabrication rate is a key indicator for evaluating the industrialization level of buildings. Its improvement can significantly reduce on-site wet operations, shorten the construction period, and reduce energy consumption and waste emissions. For example, the standardized production of prefabricated components in factories can improve quality stability, and on-site assembly construction can reduce labor dependence, which is in line with the goals of green buildings and sustainable development. At the same time, the requirements for the prefabrication rate also promote the coordinated development of the industrial chain and facilitate the standardization and informatization integration of design, production, construction, and other links.