A Brief Reading of the Notice of the Shanghai Municipal Commission of Housing and Urban-Rural Development on Further Clarifying the Implementation Scope of Prefabricated Buildings and the Calculation Rules for Individual-Building Precast Ratio and Assembly Rate
WeChat Sync · Xiaowei · 2025-05-20
On May 13, the General Office of the Shanghai Municipal Commission of Housing and Urban-Rural Development issued a document setting further requirements for the single-building precast rate and prefabrication rate of prefabricated buildings.
The document revises the Detailed Calculation Rules for the Single-Building Precast Rate and Prefabrication Rate of Prefabricated Buildings in Shanghai (Hu Jian Jian Cai [2019] No. 765) in many respects, aiming to further promote the healthy development of prefabricated buildings in Shanghai by making the implementation scope clearer, the indicator requirements more reasonable, and the calculation rules more complete. The specific revisions are as follows:
1.Implementation Scope
1.Residential Building Projects: It clarifies that in residential building projects, when the ratio of the total above-ground floor area of non-residential-function buildings to the total above-ground floor area of the project does not exceed 10%, standalone non-residential buildings such as sales offices and shops with an above-ground floor area of no more than 3000 square meters need not implement prefabricated construction. It also stipulates that residences of 3 stories or fewer (including 3 stories) need not implement prefabricated construction. Compared with Document No. 765, the new document provides a more detailed definition of the cases in which residential building projects may be exempt from prefabricated construction.
2.Public Building Projects: It stipulates that newly built public building projects with a total above-ground floor area exceeding 8000 square meters must implement prefabricated construction. Document No. 765 did not specify this area threshold; this notice provides a concrete quantitative standard.
3.Industrial Building Projects: It clarifies that newly built industrial building projects with a total above-ground floor area exceeding 8000 square meters must implement prefabricated construction; when the ratio of the total above-ground floor area of administrative office and living-service facilities in an industrial building project to the total above-ground floor area of the project does not exceed 15%, office and living quarters and standalone non-production buildings with an above-ground floor area of no more than 3000 square meters need not implement prefabricated construction; and in accordance with relevant policies, recognized major integrated-circuit manufacturing projects and shallow circular silos in newly built grain-storage facilities may be exempt from prefabricated construction. Building on Document No. 765, these provisions delineate in detail the implementation scope of prefabricated construction for industrial building projects.
4.Other Building Projects: It stipulates that newly built other building projects with a total above-ground floor area exceeding 8000 square meters must implement prefabricated construction. This is a newly added unified requirement for other types of building projects.
5.Small Ancillary Buildings: It clarifies that in newly built projects in the city, small ancillary facilities such as standalone structures, garbage rooms, ancillary equipment rooms, and guard houses need not implement prefabricated construction. Document No. 765 did not mention the prefabrication requirements for such small ancillary buildings.
2.Indicator Requirements
1.Residential Buildings of Special Height: For residential buildings taller than 100 meters (excluding 100 meters), the single-building precast rate must be no less than 15% or the single-building prefabrication rate no less than 35%; for residential buildings no taller than 18 meters (including 18 meters) and of 6 stories or fewer (including 6 stories), the single-building precast rate must be no less than 30% or the single-building prefabrication rate no less than 50%. Document No. 765 did not set such finely differentiated precast-rate and prefabrication-rate requirements for residential buildings in different height ranges.
2.Projects in Specific Industries: For main production workshops of integrated-circuit, biopharmaceutical, and artificial-intelligence industry projects included in the municipal major-project program, upon confirmation by the Municipal Major Projects Office, an application may be made to adjust the single-building precast rate of the main production workshop to no less than 20% or the single-building prefabrication rate to no less than 40% (structural units separated by structural joints may be calculated in an integrated manner). Document No. 765 contained no such provision for adjusting the indicators of main production workshops in specific industry projects.
3.Technically Special Projects: It clarifies that projects with special technical conditions may apply to adjust their precast-rate or prefabrication-rate indicators, providing an adjustment channel for special projects — content not covered by Document No. 765.
3.Calculation Rules
1.Precast Rate Calculation
1.Scope of Components: The explanation of the scope of “components” in precast-rate calculation is more detailed. For example, it further clarifies that Figures 1 and 2 show the “envelope” elements that must be counted in the denominator of the precast-rate calculation (both the walls separating indoor and outdoor environments at enclosed balconies and the exterior walls of the main building that participate in energy-saving calculations must be included), and it more clearly explains how non-load-bearing party walls and parapet panels at open balconies and similar components are counted in the numerator and the denominator under different calculation methods.
2.Volume-Proportion Method: In the volume-proportion method, for the calculation principles of steel-structure components in steel-concrete hybrid structure projects, an illustrated explanation of the cross-sectional outer contour area of steel-structure components has been added (Figure 3); it clarifies that when the total volume of the hollow parts and weight-reduction blocks in a floor-slab component exceeds 45% of the component's total volume (including the cast-in-situ composite topping), the volume of that component in both the numerator and the denominator must exclude the hollow parts and weight-reduction blocks; and it adds a provision that integrated keel-composite exterior wall panels are calculated as 200mm-thick walls for volume purposes.
3.Weight-Coefficient Method: In the weight-coefficient method, for bay windows prefabricated as a whole unit together with the wall and the upper and lower slabs, the multiplier of the “component correction coefficient” is adjusted from 1.3 to 1.2; the provisions on calculating the “precast component ratio” and on the coefficient multipliers for prefabricated long-span space frames, grid shells, and membrane structures are described in a more standardized and detailed manner; and new provisions are added that prefabricated single-bay truss beams and columns and prefabricated lattice columns are counted as one beam or one column component when calculating the “precast component ratio”, together with their coefficient multipliers.
4.Component Correction Coefficients: In Document Hu Jian Jian Cai [2025] No. 250, the correction coefficients for reinforced-concrete envelope walls and internal load-bearing wall components are calculated in a more complex way, determined comprehensively according to the five dimensions of the industrialization index plus the correction-coefficient bonus items, with detailed formulas and coefficient values provided. Meanwhile, the correction-coefficient tables for the various components (Table 2) have been adjusted: for example, the correction coefficients for fully precast beams and columns now cover more cases, including values for different proportions of cast-in-situ topping thickness in composite beams, values for fully precast concrete beams and columns with dry connections, and an addition of 0.2 to the original correction coefficient for support-free fully precast concrete beams and support-free composite concrete beams.
5.Standardization Bonus Items: It clarifies the evaluation objects, stages, and rules for the design standardization of prefabricated buildings. Residential buildings are evaluated comprehensively at the project level across all single buildings implementing prefabricated construction (except prefabricated buildings constructed with different systems); public buildings are evaluated for each single building implementing prefabricated construction (the podium portion may be excluded); and industrial buildings may follow the public-building approach for evaluating single-building design standardization. The evaluation is carried out in two stages according to Annex 2, producing the “Design Standardization Score (Scheme)” and the “Design Standardization Score (Construction Drawings)”, with the latter serving as the basis for calculating the standardization bonus. Depending on the building type, different value ranges are specified for the standardization bonus: for residential buildings and office/research public buildings, when the Design Standardization Score (Construction Drawings) S falls within different ranges, the bonus is taken as 1%, 2%, or 3% respectively; for other public buildings and industrial buildings, when the Design Standardization Score S falls within different ranges, the bonus is likewise taken as 1%, 2%, or 3%. Document No. 765 did not mention any evaluation or bonus provisions related to the design standardization of prefabricated buildings.
2.Prefabrication Rate Calculation: It clarifies that, depending on the building type, residential buildings and public buildings calculate the single-building prefabrication rate with reference to different interior-fit-out component (technology) correction-coefficient tables (Tables 3 and 4). The definitions of full interior fit-out for residential and public buildings are more detailed: for residential buildings, full fit-out means that all fixed surfaces, fixed furniture, equipment pipelines, and switches and sockets in both the common areas and the dwelling units are fully fitted out and installed, and that the fixed facilities in kitchens and bathrooms are installed in place; for public buildings, full fit-out means that all fixed surfaces, fixed furniture, fixed facilities, equipment pipelines, and switches and sockets in the common areas (including restrooms) are fully fitted out and installed, and that basic water, electricity, and ventilation equipment is installed in secondary fit-out areas. The calculation methods for component (technology) ratios and the correction coefficients of interior-fit-out components (technologies) such as non-masonry (non-cast) interior partition walls, dry-finish interior wall surfaces, integrated kitchens, integrated bathrooms, prefabricated floor systems, and pipeline separation have been refined, and content on dry-method suspended ceilings has been added to the interior-fit-out component (technology) correction-coefficient table for public buildings. Document No. 765 did not subdivide prefabrication-rate calculation by building type in this way, and its provisions on interior-fit-out components (technologies) were relatively brief.
4.Work Requirements: It clarifies the specific responsibilities of project owners, design entities, construction-drawing review agencies, construction administration departments and the management committees of specific districts, design-document review administration departments, and quality supervision departments in prefabricated building projects. For example, project owners must fulfill their primary responsibility and implement whole-process management; design entities must carry out preliminary technical planning and process design; and construction-drawing review agencies must check the project's prefabricated-building indicators against the detailed calculation rules. Document No. 765 did not set out the responsibilities of the various parties in such detail.
5.Effective Date: It stipulates that projects submitting construction drawings for review on or after September 1, 2025 must be implemented in accordance with this notice and its annex, the Detailed Calculation Rules; projects that submitted construction drawings for review before September 1, 2025 and resubmit them before December 1, 2025 due to design changes or other reasons may still be implemented in accordance with the old documents, though implementation under the new notice is encouraged; and projects resubmitting construction drawings for review due to design changes on or after December 1, 2025 must strictly follow this new notice and its annex, the Detailed Calculation Rules. Document No. 765 did not address such implementation provisions for projects submitting construction drawings for review at different points in time.
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