The interface for charging superheight increment / efficiency-loss costs on separately tendered building decoration works (including door and window renewal): the trigger-height gate, the work-content gate and the tendering / pricing interface, and how to judge them

Topic Positioning

This card answers the pricing-interface question "may separately tendered building decoration works (including door and window renewal) charge the superheight increment / efficiency-loss cost", giving the three-gate framework current in cost practice (trigger height, work content, tendering / pricing interface) with the verbatim clauses of local and sector consumption standards.

Core Conclusions

1. The trigger gate (height / storeys)

• Hunan 2024 building and decoration consumption standard (2025 edition in the source data), chapter 21 superheight increment cost, note 1: "where the building eaves height exceeds 20 m, the superheight increment cost is computed under this standard"; note 2: "where a building has different eaves heights, split vertically by eaves height, compute floor areas separately, and apply the corresponding items by each eaves height".
• Jiangsu 2024 consumption standard (2026 edition in the source data), chapter 20 superheight efficiency loss of building works, note 1: "where the structural height from outdoor design ground to floor level exceeds 20 m, or the storeys exceed 6, the superheight efficiency loss is chargeable"; note 3: "either the 'height' or the 'storeys' indicator reaching the rule allows the item".
• Repair and refurbishment works carry a stricter gate: Beijing DB11/T 638-2016 Quantity Measurement Code for Building Repair Works, table B.9.2 note 1 (and Annex A.19.4 item 2): "the superheight increment cost is chargeable only where the work point exceeds 25 m; where the building exceeds 25 m but the work point does not, it must not be used." Door and window renewal of a repair nature follows the repair basis of the project location.

2. The work-content gate (are doors and windows within the superheight scope)

• Hunan 2024, measurement rule 1: "for chapters 11 to 17, the superheight increment cost is computed on the labour and plant costs of the corresponding quantities above 20 m eaves height times the coefficient"; rule 2: "for the other chapters, by the floor area above 20 m eaves height". Note 4: "the superheight increment cost of decoration chapters 11 to 17 is computed on labour plus plant times the superheight coefficient in the table below." Door and window works sit in the decoration chapters 11 to 17 and take the "labour + plant x coefficient" basis.
• Jiangsu 2024, note 2: building superheight efficiency loss "excludes vertical transport of building works, member transport and erection, comprehensive scaffolding, lift-shaft frames, chimney and water-tower scaffolds, and fabrication of site-precast concrete and steel members"; measurement rule: "the base of the efficiency-loss coefficient is the labour cost of the parts above 20 m structural height or 6 storeys." That is, the loss is charged on the labour of the superheight part, by the storey coefficient.
• Conclusion: doors and windows are decoration-works content and clear this gate; charge per the local decoration superheight basis (superheight labour, or labour plus plant, x coefficient).

3. The tendering / pricing interface

• Shenzhen SJG 77-2020 Standard for Dividing Work Items and Preliminary Items in Building Works Cost Documents, clause 5.1.4: "the superheight construction increment cost shall be included in the all-in unit rate of each bill item." The cost travels with the item's all-in rate into the corresponding contractor's contract price.
• For separately tendered decoration works - BOQ pricing or quota pricing alike - charge on the storey where the superheight items sit, at the superheight items' labour (in some regions labour plus plant) times the coefficient, only for the superheight portion of the decoration quantities. Where the tender BOQ or contract does not allot it to the door-and-window subcontractor, or the main contractor has capped it, the subcontractor may not claim it separately.

4. The railway building-works basis TB/T 10831-2024 Railway Works Budget Quota Manual, Volume 10 building works, chapter 1 section 8 "vertical transport and superheight", item 2 "building superheight increment cost" sets: FY-1026 (eaves over 20 m up to 40 m), FY-1027 (over 40 m up to 60 m), FY-1028 (each additional 10 m of eaves), unit 100 m2; work content includes "reduced worker efficiency on shift, added time going up and down and for natural rest, time affected by vertical transport, plant efficiency loss induced by labour loss, and booster-pump machine-shifts where water pressure falls short".

Applicability Boundaries

• The trigger differs by system: building / decoration systems mostly use "eaves over 20 m or storeys over 6" (either suffices); repair / refurbishment systems use "work point over 25 m" (DB11/T 638-2016) - a building over the line with the work point under it takes nothing.
• Whether door and window renewal may charge "separate decoration superheight" depends on the works' nature (repair or decoration) and the contract interface; projects with the main works complete and only facade / interior fit-out (including door and window replacement) follow the separate-decoration labour-loss basis and no longer take the main-works "building superheight increment cost" by floor area.
• Against double counting: one superheight loss cannot be claimed by main contractor and subcontractor alike; main-works superheight and decoration superheight must not both be charged.
• Coefficients, item rates and base definitions follow the project location's current consumption standard / quota; this card does not replace local pricing bases.
• This card states the prevailing sector and local positions; details (coefficient values, whether the base includes plant) differ by region - check the current local documents before use.

Further Reading

• Hunan 2024 building and decoration consumption standard (2025 edition in the source data), chapter 21 superheight increment cost (notes and measurement rules)
• Jiangsu 2024 building and decoration consumption standard (2026 edition in the source data), chapter 20 superheight efficiency loss of building works and chapter 21 construction dewatering and drainage
• DB11/T 638-2016 Quantity Measurement Code for Building Repair Works, table B.9.2 notes 1-2, Annex A.19.4 questions and notes
• SJG 77-2020 Standard for Dividing Work Items and Preliminary Items in Building Works Cost Documents, clause 5.1.4
• TB/T 10831-2024 Railway Works Budget Quota Manual, Volume 10 building works, chapter 1 section 8 vertical transport and superheight, item 2 building superheight increment cost (FY-1026 to FY-1028)
• Railway vertical-transport chapter: chapter 20 items (builder's hoists per "machine-day", other vertical transport per 100 m2)