Pricing of steel-framed glass daylighting roofs (glass skylights): the daylighting sub-items include the framing, spider-fitting installation transfers to the curtain-wall chapter with labor x 0.90, and independent steel supporting frames are itemized separately in tonnes under metal-structure works (Beijing DB11/T 2382-2024 basis)

Topic Positioning

Pricing and sub-item selection for steel-framed glass daylighting roofs (glass skylights). Based on the quota basis of Beijing DB11/T 2382-2024 "Construction Consumption Standard" and the BOQ basis of GB/T 50854-2024, three pricing routes are given (glass + accompanying framing under one daylighting sub-item / spider fittings transferring to the curtain-wall chapter / independent supporting steel frames itemized separately under metal-structure works), together with points against double counting and omissions.

Core Conclusions

I. The decisive rule (whether the framing is itemized separately) DB11/T 2382-2024 Clause 4.10.5, original text: "The construction consumptions of polycarbonate-panel roofs and daylighting roofs shall be determined as required by the design drawings and shall include the work content of the framing (frame); where the design drawings require installation with spider fittings, it is advisable to execute the provisions of Clauses 4.13.1 to 4.13.28 of this standard, with the labor consumption multiplied by a factor of 0.90." -> For conventional steel/aluminium-framed glass daylighting roofs: the glass together with its accompanying framing (frame) is priced under one "daylighting roof" sub-item; the framing is not itemized separately, and the glass and framing must not be split apart and double-counted.

II. Sub-items for conventional framing systems (Table A.9.1-4 daylighting roof, unit m2) The work content of each sub-item is uniformly: "cutting; fabricating and installing the framing support; applying protective materials and paint; installing the glass, packing joints, applying sealant and sealing" - framing fabrication and installation, protective paint and sealing are all included.

• A-9-46 insulating laminated glass installed on aluminium framing: comprehensive labor Cat. II 0.8060 work-days; laminated glass 0.9700 m2; aluminium frame skeleton 5.0237 kg; sealant 750 ml 0.2040 cartridges; heat-resistant rubber gasket 2 mm x 38 mm 1.6981 m; galvanized hex bolts 10.9500 sets.
• A-9-47 insulating laminated glass installed on steel framing: comprehensive labor Cat. II 1.0040 work-days; laminated glass 1.0700 m2; steel framing sections totalling about 24.6 kg (channel 63 x 40 x 4.8 mm 19.6630 kg, flat bar 5 mm 3.9965 kg, flat bar 100 x 10 mm 0.7686 kg, T-steel 25 x 25 mm 0.2078 kg), plus iron fittings 0.7465 kg etc.
• A-9-48 (insulating laminated glass installed on aluminium framing; the material column shows tempered glass 6 mm 1.0917 m2 and steel sections totalling about 10.9 kg): comprehensive labor Cat. II 0.6780 work-days. The consumptions are determined as required by the design drawings; where the design differs greatly from the sub-item configuration/contents, adjust and convert per the item features; before application, verify the correspondence of sub-item names and material composition against the original tables of the standard. Quantities: Clause 4.10.19(2) - "polycarbonate-panel roofs and daylighting roofs shall be calculated by area per the dimensions shown on the design drawings, without deducting the areas occupied by individual holes of not more than 0.30 m2".

III. Spider-fitting (point-supported) route Per 4.10.5, execute under Chapter 4.13 Curtain Wall Works, with labor consumptions x 0.90; curtain-wall works "shall set items and determine consumptions separately for finished framing, hardware and the skin" (4.13.14), and curtain-wall steel and aluminium framing shall be calculated by mass per the design dimensions (4.13.26(1)). Sub-item examples: A-12-262 steel framing (t; comprehensive labor Cat. I 24.0390 work-days/t; sections 1.060 t/t); A-12-264 steel framing (m2; comprehensive labor Cat. I 0.1440 work-days/m2). Curtain-wall sub-items do not include the work content of embedded parts (4.13.14); embedded parts are itemized separately under the Clause 4.6.9 system.

IV. Independent supporting steel frames (steel skylight trusses, steel beams, trusses etc.) Structural supporting frames beyond the scope of the "framing (frame)" are itemized separately by mass (t) under A.6 Metal-Structure Works. Sub-item example: A-6-27 steel skylight truss (t; comprehensive labor Cat. I 4.8160 work-days/t; materials: finished steel skylight truss 1.000 t/t, welding electrodes 2.6400 kg). Key points:

• Clause 4.7.11, original text: "The construction consumptions of metal members shall not include the consumptions of paint and fireproof coatings; where the design drawings impose anti-corrosion or fire-resistance requirements, the provisions of Clauses 4.15.1 to 4.15.10 of this standard shall be executed, except for the paint already applied to the surfaces of finished steel members";
• Quantities are calculated by mass per the design dimensions, without deducting the mass of holes; welding electrodes, rivets and bolts add no additional mass (4.7.12 to 4.7.17).

V. BOQ basis (GB/T 50854-2024)

• Appendix M M.8.14: glass daylighting roofs and metal-panel roof claddings within curtain-wall works shall be itemized using the relevant items of Appendix J Roofing and Waterproofing Works (roofing code 010901);
• Appendix J J.6.2: the supporting structures of polycarbonate-panel and GRP roofs (roof trusses, purlins etc.) shall be itemized using the relevant items of Appendix F Metal-Structure Works and Appendix G Timber-Structure Works - independent supporting structures are not merged into the roofing items.

VI. Points against double counting / omissions

• The daylighting sub-items already include framing fabrication and installation, protective paint and sealing; do not re-apply framing/paint/sealant sub-items;
• The two routes (conventional framing directly under a daylighting sub-item / spider fittings transferring to curtain wall x 0.90) must not be mixed;
• Independent steel frames are itemized separately in t, clearly bounded against the framing (frame) inside the sub-items; anti-corrosion and fireproof coatings are charged separately per 4.7.11;
• Embedded/post-installed anchor parts are itemized separately (4.13.14); edge flashings, openable-sash hardware, and measures costs such as scaffolding are charged separately.

Applicable Boundaries

• The quota basis is Beijing DB11/T 2382-2024 (2024 consumption standard) and the BOQ basis is GB/T 50854-2024; other provinces/cities shall follow their local consumption standards/quota sub-items and factors and must not mix them directly.
• The daylighting-roof consumptions are "determined as required by the design drawings"; before application, check the design configuration (glass build-up, framing material and content) against the sub-item contents, and adjust/convert where the differences are large.
• Quota consumption figures are subject to the original text of the standard and its errata; verify item features and design configuration before application.

Further Reading

• DB11/T 2382-2024 Clauses 4.10.5 and 4.10.19; Appendix A Table A.9.1-4 daylighting roof (sub-items A-9-46 to A-9-48);
• The same standard Clauses 4.13.14 and 4.13.26 (curtain-wall works) and Clauses 4.7.11 to 4.7.17 (metal-structure works);
• GB/T 50854-2024 Appendix J Table J.1.1 (roofing code 010901), Appendix M M.8.14, Appendix J J.6.2.