Building automation system (BAS) / HVAC automatic control - BOQ item setting and appendix attribution under GB/T 50856-2024 Appendix E (code 030503)

Topic Positioning

Clarifies the BOQ code, item-setting rules and appendix attribution of HVAC automatic control / building automation (building automation system, BAS) under GB/T 50856-2024 "Standard for Calculation of Quantities of General Installation Works", resolving the trade-attribution and interface question of "which BOQ items / quota items apply to building automation".

Core Conclusions

1. Attribution determination: HVAC automatic control and building automation (BAS) correspond to the "building automation system" of the standard, BOQ code 030503, listed under Appendix E Building Intelligentization Engineering. The standard provides: "The setting of quantity-list items of the building automation system, the content of item feature descriptions, the units of measurement and the quantity calculation rules shall follow the provisions of Table E.3.1." Table E.3.1 sets items such as communication network control equipment (030503001) and controllers (030503002); the unit of measurement is "unit (set)" and quantities are calculated as shown on the design drawings; the work content includes equipment installation, connection, software installation and testing, and function/parameter setting (the definitive item setting is subject to the standard text).
2. Civil vs. industrial division (Appendix E chapter notes): the standard states - "This chapter applies to construction projects of civil automation systems; industrial automation systems shall be itemized using the corresponding item codes of Appendix F Automation Control Instrument Installation Engineering of this standard." That is, civil buildings (including conventional HVAC automatic control) use Appendix E code 030503, whereas industrial automation (DCS/PLC-type instrument control) must not apply Appendix E.
3. Definition of installation method (Appendix E chapter notes, original wording): "Installation method refers to the installation form of the equipment, such as floor-standing installation, ceiling-mounted installation, or installation in racks (cabinets, plug-in boxes)."
4. Interfaces of associated works (Appendix E chapter notes, original wording): "Electrical equipment, electrical devices, battery banks, lightning-protection and earthing systems, pole erection, conduit works, raceways, cable trays and junction boxes associated with the building intelligentization works covered by this chapter shall be itemized using the corresponding item codes of Appendix D Electrical Equipment Installation Engineering of this standard." That is, the BAS controllers and field devices use 030503, while their conduit, raceways, cable trays, junction boxes and electrical equipment are itemized under Appendix D, avoiding double counting under both appendices.

Applicable Boundaries

• Applicable to: general installation works whose BOQs are compiled under GB/T 50856-2024, and HVAC automatic control / building automation (BAS) items of civil buildings.
• Not applicable to: industrial automation systems (industrial DCS/PLC, instrument control) shall be itemized under Appendix F Automation Control Instrument Installation Engineering and must not use the Appendix E building automation system items.
• This card resolves "BOQ item attribution and trade interfaces" and does not cover the specific sub-item selection and unit-rate bases of local consumption standards; when applying quota sub-items, use the current consumption standard of the project location and check item features and quantities against the design point schedule / system diagrams.

Further Reading

• GB/T 50856-2024 "Standard for Calculation of Quantities of General Installation Works", Appendix E Building Intelligentization Engineering: Table E.3.1 (030503 building automation system) and the chapter notes (including the civil/industrial division and the rule that conduit, trays and junction boxes are itemized under Appendix D);
• Measurement rules for associated electrical works, conduit, raceways, cable trays and junction boxes: Appendix D Electrical Equipment Installation Engineering;
• Industrial automation instrument control: Appendix F Automation Control Instrument Installation Engineering.