Beijing DB11/T 2382-2024 consumption standard: rules for determining whether pipe installation quota line items include pipe fittings - in the gas chapter only galvanized steel pipe (threaded joints) items include fittings and pipe clamps while fittings of other materials are billed separately; pipe items of the water supply/drainage and heating chapters include fitting installation

Topic Positioning

Within Chapter 6.10 "Water supply and drainage, heating and gas works" of the general installation works of Beijing DB11/T 2382-2024 "Construction Consumption Standard": the rules for determining whether a pipe installation quota line item includes the installation of pipe fittings - first locate the discipline chapter (gas vs water supply/drainage and heating), then the pipe material and jointing method; the same material can yield opposite conclusions in different chapters. Used when applying the consumption standard, building up rates and listing BOQ items, to decide whether "pipe (m)" and "fittings (piece)" are listed separately and whether separate fitting items may be applied.

Core Conclusions

1. Two general rules (original clause wording)

1. Gas piping (clause 6.10.34): "The construction consumptions for installation of galvanized steel pipe (threaded joints) shall include the work content of fittings and pipe-clamp installation; for pipes of other materials, the installation of fittings and pipe clamps shall follow the corresponding fitting and pipe-clamp installation items." -> In the gas chapter only the galvanized steel pipe (threaded joints) items include fitting and pipe-clamp installation; for all other materials (welded steel pipe, PE pipe, steel-skeleton plastic composite pipe etc.) the fittings and clamps must be applied against the corresponding "fitting and pipe-clamp installation" items.

2. Indoor water supply, drainage, rainwater, heating and air-conditioning water piping (clause 6.10.32): "The construction consumptions for pipe installation shall include the fitting installation content; fitting material quantities may be calculated as the design-shown quantities, or as stipulated in Table 6.10.32." -> In the water supply/drainage and heating chapters the pipe items themselves include fitting installation, so no separate "fitting installation" item may be applied (that would be double counting); fitting material quantities follow the design-shown quantities or Table 6.10.32.

2. Material-by-material determination (corroborated by the appendix line items)

• Gas welded steel pipe: the pipe item excludes fittings; fittings follow the "steel fittings (welded)" items (unit: piece; work content includes edge preparation, alignment, argon-arc root runs, welding and grinding). E.g. item C10-3-103 for outside diameter up to 48 mm contains per piece 1.01 gas steel fittings, 0.0975 kg of welding electrodes and 0.0321 machine-shifts of argon-arc welding machine; item C10-3-105 for outside diameter up to 89 mm contains 1.01 gas steel fittings per piece.
• Gas galvanized steel pipe (threaded joints - the only "included" exception): the item (e.g. C10-3-82, nominal diameter up to 50 mm) carries the work content "pipe and fitting installation, thread painting, pipe-clamp installation, purging, strength test and tightness test", with consumptions of 1.02 m/m galvanized steel pipe, 0.688 gas steel fittings per metre and 0.45 clamp-type materials per metre - exactly matching clause 6.10.34.
• Gas PE pipe (electrofusion / butt-fusion joints): falls under "pipes of other materials" in clause 6.10.34; fittings and clamps follow the corresponding fitting installation items.
• Steel-skeleton composite pipe: for water-supply use (outdoor water-supply steel-skeleton plastic composite pipe, electrofusion joints) the pipe item includes fitting installation - the work content expressly reads "pipe and fitting installation, hydraulic test, water flushing", and the consumption table lists fitting quantities (item C10-1-94 for nominal diameter up to 70 mm: 0.281 fittings/m, 0.0103 machine-shifts/m of electrofusion welding machine); for the metal-skeleton composite pipe family a separate "metal-skeleton composite fittings (electrofusion)" item is provided (unit: 10 pieces, e.g. C8-4-315), fittings and pipes being set as separate items counted by number.
• Related rules: fabrication and erection of pipe supports, clamps and hooks follow clauses 6.10.39-6.10.42; the gas leak-detection pipe follows the pipe installation items, and the tracer wire follows the warning-tape installation item (6.10.35, 6.10.29).

3. Measurement rules (identical in both chapters)

• 6.10.36: pipe installation quantities are calculated as the length of the design-shown pipe centreline, without deducting the lengths occupied by fittings, valves and accessories.
• 6.10.37: fitting installation quantities are calculated as the design-shown number of pieces.
• 6.10.38: warning-tape installation quantities are calculated as the design-shown quantities.
• That is: where fittings are billed separately, "pipe (m)" and "fittings (piece)" are two independent BOQ items counted independently; where fittings are not billed separately, the fitting material quantities are merged into the pipe item.

Applicable Boundaries

• Applies to Beijing construction works governed by DB11/T 2382-2024; determination sequence: first locate the chapter (gas 6.10.34 / water supply-drainage and heating 6.10.32), then the material and jointing method, and finally decide whether fittings are billed separately.
• Where the pipe item already includes fitting installation, no further "fitting installation" may be applied (double counting); in gas works, except for galvanized steel pipe (threaded joints), fittings and pipe clamps must not be omitted.
• This card centres on Chapter 6.10 of the general installation works; gas pipe laying under the municipal pipe-network works (Chapter 7.4, where 7.4.39: installation quantities of fittings, valves, flanges and accessories are calculated as the design-shown number of pieces) must be checked separately against the municipal chapters.
• The applicability of specific line items is subject to the current text of the standard and its appendices; details of fitting material quantities taken as the design-shown quantities or per Table 6.10.32 should be verified against the original tables of the standard.

Further Reading

• DB11/T 2382-2024 "Construction Consumption Standard", Chapter 6.10 "Water supply and drainage, heating and gas works": 6.10.24-6.10.32 (indoor piping), 6.10.33-6.10.38 (gas piping), 6.10.39-6.10.42 (pipe supports etc.); the same chapter also contains the rainwater-pipe conversion (6.10.27), electrofusion taken as butt fusion (6.10.28), coefficient adjustments for disinfection-flushing / ball-passing tests (6.10.30) and similar rules, to be checked together when applying items.
• Appendix C, relevant line-item tables of the general installation works: C10-1 series (water supply and drainage, e.g. C10-1-94 outdoor water-supply steel-skeleton plastic composite pipe, electrofusion joints), C10-3 series (gas, including C10-3-82 galvanized steel pipe threaded joints and C10-3-103/C10-3-105 steel fittings, welded), C8-4 series (metal-skeleton composite fittings, electrofusion joints).
• Chapter 7.4 "Municipal works - pipe network works" VII gas pipe laying (7.4.33-7.4.43): laying of gas anti-corrosion steel pipe / plastic pipe, fittings-valves-flanges counted as the design-shown number of pieces, cleaning and purging, valve chambers and other attached structures.