Quantity-calculation caliber for aluminum (metal) panel curtain walls: computed by the design outer surface / frame-perimeter area, not by the developed fabrication area of the aluminum sheet; projected area is the unitized-curtain-wall caliber, and developed area applies only to rib-stiffened full-glass walls (BOQ and quota calibers compared)

Topic Positioning

This card distinguishes the quantity-calculation caliber for aluminum (metal) panel curtain walls: computed by the design outer surface / frame-periphery area, not by the developed fabrication area of the aluminum sheet; projected area is specific to unitized walls; developed area applies only to rib-stiffened full-glass walls. It also compares the BOQ (GB/T 50854-2024) and quota (Beijing DB11/T 2382-2024, railway TB/T 10831-2024, Jiangsu 2026) calibers with practice points.

Core Conclusions

1. BOQ caliber (GB/T 50854-2024 Standard for Measurement of Building and Decoration Works, Appendix M, Table M.6.1 curtain wall works, code 011206)

• Component-type metal-panel walls (aluminum included): computed by the design-shown outer surface area — not by the sheet's developed fabrication area; for vertical planes this is the frame-periphery (front-projected) area; recessed/faceted shapes follow the design-shown wall outer surface, without flattening the projection;
• Component-type glass walls: by the design frame-periphery area, deducting openable sashes;
• Unitized walls: by the design frame-periphery projected area, deducting openable sashes.

2. Quota caliber (Beijing DB11/T 2382-2024, Clause 4.13.26)

• Item 4: "curtain-wall face courses are computed by area per design dimensions";
• Item 5: glass walls "by design frame-periphery area, without deducting windows of the same material as the wall"; Item 6: full-glass (frameless) walls by design dimensions;
• Clause 4.13.14, Item 3: "curtain-wall construction consumptions are preferably determined for planar, non-respirating walls; for curved, faceted, and respirating walls the labor consumption of the relevant items may be adjusted" — special-shape walls adjust by labor coefficient, not by recomputing developed area (coefficient adjustment and area caliber are two separate tracks — avoid double compensation).

3. Panel folding is not quantity

• Jiangsu 2026 building and decoration consumption standard, aluminum single-panel wall sub-item note: "the folded-edge area of finished aluminum single panels is considered in the material price";
• Beijing sub-item A-12-269 "metal panel face course (single panel area within 1.2 m2)": aluminum panel consumption 1.0300 m2 (relative to the face measurement, including loss allowance), other materials 1.5%, other tools 2% — the folding is absorbed in material loss/price, not added as area.

4. Corroboration (TB/T 10831-2024 Budget Quota for Railway Works, Vol. 10: Buildings, volume notes "curtain walls, partitions") "Glass and aluminum panel curtain walls are computed by the frame-periphery area; semi-glass partitions and full-glass walls, where stiffened with ribs, are computed by their developed area" — developed area is reserved for rib-stiffened full-glass walls; aluminum walls are by frame periphery.

5. Practice points BOQ and quota quantities follow their own rules; do not use the BOQ number directly as the quota number; for curved/faceted/special shapes, first check the local consumption standard's adjustment rule (Beijing: "labor consumptions may be adjusted"), not area redevelopment; where the contract/tender documents stipulate a special caliber (e.g., shaped panels by development), follow the agreement.

Applicable Boundaries

• Applies to face-course quantity calculation for curtain walls (aluminum/metal focus) in building and decoration works; BOQ and quota are two calibers computed separately, not to be mixed;
• The "developed area" exception appears only in special provisions such as rib-stiffened full-glass walls (TB/T 10831-2024) and must not be extended to aluminum walls;
• Regional differences: Beijing per DB11/T 2382-2024, others per local standards (e.g., Jiangsu 2026); wording of special-shape adjustments and folding treatment may differ;
• This card covers only the face-course area caliber; non-face items (steel/aluminum mullions by mass, glass fins by area, hardware by count or length) follow their own rules.

Further Reading

• GB/T 50854-2024 Standard for Measurement of Building and Decoration Works, Appendix M, Table M.6.1 curtain wall works (code 011206) — units and rules per wall type;
• DB11/T 2382-2024 Consumption Standard for Construction Works, Clauses 4.13.14 and 4.13.26; Appendix A Table A.12.9-3 curtain-wall face courses (sub-item A-12-269);
• TB/T 10831-2024 Budget Quota for Railway Works, Vol. 10: Buildings, volume notes "(IV) curtain walls, partitions";
• Jiangsu building and decoration consumption standard (2026 edition), aluminum single-panel wall sub-item notes.