What is the AS/NZS 3000 Table C3 energy demand method?

Table C3 of AS/NZS 3000:2018 Appendix C is titled "Maximum demand: energy demand method for non-domestic installations". Instead of itemising every load, it gives an energy demand density in volt-amperes per square metre for each type of occupancy (a range and a typical average), which is multiplied by the floor area to give the demand. It is the practical method at concept and schematic design, when the floor plate and occupancy are known but the equipment schedules are not.

What VA/m² does Table C3 give for retail shops and warehouses?

Retail shops are tabulated at 40–100 VA/m² (average 70) for light and power, plus 20–40 VA/m² (average 30) for air conditioning. Warehouses are 5–15 VA/m² (average 10) for light and power plus 5 VA/m² for ventilation, with special equipment to be added from actual load details. Light industrial buildings are 10–20 (average 15) light and power, 10–20 (average 15) ventilation and 30–50 (average 40) air conditioning, again with special equipment by load details.

Do I add air conditioning on top of the Table C3 light and power density?

Yes, for the occupancies where Table C3 lists them separately. Offices, retail shops, warehouses and light industrial buildings have a light-and-power density and a separate air-conditioning or ventilation density, and the two are added. Taverns, licensed clubs and theatres are different: they are tabulated as a single total (60–100 and 80–120 VA/m² respectively), so no separate air-conditioning figure is added.

Does Table C3 include EV charging?

Yes, as a separate addition. Table C3 tabulates EV charging at 5–15 VA/m² (average 10) for open-air carparks and 10–30 VA/m² (average 20) for basement carparks, and notes that it should be considered in addition to all other energy demands rather than being included within the carpark density.

Does Table C3 give a higher or lower demand than Table C2?

It depends on the building type and load mix. The Table C3 densities describe a typical fit-out for the occupancy, whereas Table C2 diversifies the loads that are actually scheduled, so the two agree closely on a conventional building and diverge where the fit-out is unusual. Many designers run Table C3 at concept stage and recalculate with Table C2 once the equipment schedules are firm.

Can Table C3 be used as the final design demand?

AS/NZS 3000:2018 Clause 2.2.2 permits maximum demand to be determined by calculation or assessment, and Appendix C (including the Table C3 energy demand method) is the guidance given for that. The practical caution is that a floor-area density cannot see an atypical fit-out, so confirm the result against the actual load schedule and your distributor's service and installation rules before it becomes the design figure.

ElecAS

Table C3 Energy Demand Calculator: Maximum Demand from Floor Area (VA/m²) to AS/NZS 3000:2018

Free, browser-based calculator implementing the AS/NZS 3000:2018 Appendix C Table C3 energy demand method, which assesses the maximum demand of a non-domestic installation from its floor area in volt-amperes per square metre rather than from an itemised load schedule. Table C3 tabulates a VA/m² range and a typical average for each type of occupancy: offices at 40–60 VA/m² (average 50) for light and power with air conditioning added separately by system type (cooling 30–40, reverse cycle 20–30, zonal reheat 40–60, variable volume 20); retail shops at 40–100 (average 70) plus air conditioning 20–40; warehouses at 5–15 (average 10) plus ventilation 5; light industrial at 10–20 light and power, 10–20 ventilation and 30–50 air conditioning; carparks at 0–10 open air and 10–20 basement; taverns and licensed clubs at a total of 60–100 (average 80); and theatres at a total of 80–120 (average 100). Electric vehicle charging is tabulated separately for carparks (5–15 VA/m² open air and 10–30 VA/m² basement), and Table C3 notes it should be considered in addition to all other energy demands. The calculator takes one row per area with separate light, power and mechanical services densities so the light-and-power and air-conditioning entries stay distinguishable, loads occupancy presets built from the tabulated values, accepts non-area loads (the "special equipment: use load details" entries) as assessment items in watts or amperes, and applies optional overall diversity and spare capacity. It returns the total in volt-amperes and amperes per phase at 230 V single-phase or 400 V three-phase, with a per-area breakdown and a branded PDF report.

Key facts

Table C3 is the energy demand method for non-domestic installations: it assesses maximum demand from floor area in volt-amperes per square metre (VA/m²), tabulated by type of occupancy.
Each occupancy row gives a range and an average. Offices are 40–60 VA/m² (average 50) for light and power, with air conditioning added separately: cooling 30–40 (35), reverse cycle 20–30 (25), zonal reheat 40–60 (50) and variable volume 20 VA/m².
Retail shops are 40–100 VA/m² (average 70) for light and power plus 20–40 (30) for air conditioning; warehouses are 5–15 (10) plus 5 for ventilation; light industrial is 10–20 (15) light and power, 10–20 (15) ventilation and 30–50 (40) air conditioning.
Taverns and licensed clubs are tabulated as a total of 60–100 VA/m² (average 80), and theatres as a total of 80–120 VA/m² (average 100).
Carparks are 0–10 VA/m² (average 5) open air and 10–20 (15) basement, and Table C3 notes that EV charging (5–15 VA/m² (10) open air, 10–30 (20) basement) is to be considered in addition to all other energy demands.
Where the occupancy has special equipment, Table C3 directs you to use the actual load details rather than a VA/m² density.

Who this page is for

Electrical engineers, building services designers and estimators sizing consumer mains, substations and switchboards for offices, retail, warehouses, light industrial buildings, carparks, taverns, clubs and theatres at concept or schematic design, before equipment schedules exist, and anyone cross-checking a Table C2 itemised result against a floor-area benchmark.

Relevant standards

AS/NZS 3000:2018 (Wiring Rules: Clause 2.2.2 determination of maximum demand by calculation, assessment, measurement or limitation)
AS/NZS 3000:2018 Appendix C Table C3 (Maximum demand: energy demand method for non-domestic installations, VA/m² by type of occupancy)
AS/NZS 3000:2018 Appendix C Table C2 (the itemised load-group method the Table C3 result is normally cross-checked against)

What this tool helps with

Applies the AS/NZS 3000:2018 Table C3 energy demand method: maximum demand assessed from floor area in volt-amperes per square metre, by type of occupancy.
Occupancy presets carry the tabulated Table C3 densities for offices, retail shops, warehouses, light industrial buildings, basement carparks and taverns or licensed clubs, and every density stays editable for a project-specific figure.
Keeps light, power and mechanical services as separate VA/m² fields per area, so the Table C3 light-and-power entry and the air-conditioning or ventilation entry remain visible and auditable instead of collapsing into one number.
Handles a building as a list of areas (office floor, retail tenancy, warehouse, basement carpark) each with its own description, floor area and densities, so a mixed-occupancy building is assessed in one calculation.
Accepts the "special equipment: use load details" entries that Table C3 flags for warehouses and light industrial buildings as assessment loads in watts or amperes, rather than forcing process, refrigeration or workshop plant into a floor-area density.
Supports the Table C3 note that EV charging in carparks (5–15 VA/m² open air, 10–30 VA/m² basement) is to be considered in addition to all other energy demands.
Applies optional overall diversity and spare capacity as their own lines in the breakdown, and reports the result in both volt-amperes and amperes per phase at 230 V single-phase or 400 V three-phase.
Exports a branded PDF report showing each area, its floor area, its densities and its contribution, ready for the concept design record and for comparison against a later Table C2 calculation.
Built and reviewed by a Chartered Professional Engineer (CPEng, NER, NSW DBP, NSW PRE, APEC, IntPE Aus): see the Verification page for the testing and review process.

How to calculate maximum demand using the AS/NZS 3000 Table C3 energy demand method

Set the supply configuration: Select single-phase (230 V) or three-phase (400 V). Table C3 gives the demand in volt-amperes, which the calculator converts to amperes per phase.
Add one row per area: Add a row for each distinct area or occupancy in the building (office floor, retail tenancy, warehouse, basement carpark) with its description and floor area in square metres.
Apply the Table C3 densities: Load the preset for the occupancy or enter the VA/m² figures yourself: light and power in the light and power fields, and the air conditioning or ventilation density in the mechanical field. Use the tabulated average unless the fit-out is known to be at the intensive or sparse end of the range.
Add EV charging separately for carparks: Table C3 notes that EV charging is in addition to all other energy demands. For an open-air carpark add 5–15 VA/m² (average 10) and for a basement carpark 10–30 VA/m² (average 20) on top of the carpark density.
Add special equipment as assessment loads: Warehouse and light industrial occupancies list special equipment as "use load details". Add process plant, refrigeration, workshop equipment and similar as assessment items in watts or amperes rather than folding them into a VA/m² density.
Apply diversity and spare capacity if the brief requires them: An overall diversity factor and a spare-capacity percentage can be applied on top of the Table C3 total. Both appear as separate lines so the raw Appendix C figure stays visible.
Review the total and export the report: Check the per-area breakdown, compare the result against your distributor's requirements and against a Table C2 itemised calculation once the equipment schedules firm up, then export the branded PDF for the design record.

AS/NZS 3000:2018 Table C3: the energy demand method (VA/m²) for non-domestic installations

What the Table C3 energy demand method is

AS/NZS 3000:2018 Appendix C Table C3 ("Maximum demand: energy demand method for non-domestic installations") assesses the maximum demand of a non-domestic installation from its floor area rather than from an itemised load schedule. For each type of occupancy the table gives an energy demand density in volt-amperes per square metre (a range and a typical average), which is multiplied by the floor area to give the demand in volt-amperes, and then converted to amperes per phase.

It is the practical method at concept and schematic design, when the floor plate and the occupancy are known but the equipment schedules are not. It is also the fastest sanity check on a Table C2 itemised result: if a 2000 m² office assesses at far less than 2000 × 50 VA = 100 kVA of light and power, something in the load schedule is probably missing.

The tabulated densities

Offices: light and power 40–60 VA/m², average 50. Air conditioning is tabulated separately by system type (cooling 30–40 (average 35), reverse cycle 20–30 (25), zonal reheat 40–60 (50) and variable volume 20 VA/m²), and is added to the light and power figure.

Retail shops: light and power 40–100 VA/m², average 70; air conditioning 20–40, average 30. Warehouses: light and power 5–15, average 10; ventilation 5; special equipment by load details. Light industrial: light and power 10–20, average 15; ventilation 10–20, average 15; air conditioning 30–50, average 40; special equipment by load details.

Carparks: open air 0–10 VA/m², average 5, and basement 10–20, average 15. Taverns and licensed clubs are given as a single total of 60–100 VA/m², average 80. Theatres are given as a single total of 80–120 VA/m², average 100.

Table C3 carries an explicit note on electric vehicle charging: the EV charging densities (5–15 VA/m² (average 10) for open-air carparks and 10–30 VA/m² (average 20) for basement carparks) relate to charging equipment associated with electric vehicles and should be considered in addition to all other energy demands, not as part of them.

How to use the range rather than the average

The average column is the sensible default at early design. Move toward the top of the range where the fit-out is known to be intensive (dense open-plan workstations, high-illuminance retail, a hot climate zone with a large glazed façade), and toward the bottom where the occupancy is sparse or the lighting is a modern low-power-density LED design.

Where an occupancy carries a "special equipment (use load details)" entry (warehouses and light industrial do) the density covers the base building only. Process plant, refrigeration, workshop equipment and data-centre loads have to be added at their actual connected load, assessed separately, rather than absorbed into a VA/m² figure.

What the calculator does

The ElecAS Table C3 calculator takes one row per area: a description, the floor area in square metres, and three VA/m² densities (light, power and mechanical services), so the light-and-power and air-conditioning or ventilation entries from Table C3 can be carried separately and still be seen in the breakdown. Presets for office, retail shop, warehouse, light industrial, basement carpark and tavern or club load the tabulated Table C3 densities, and every field stays editable so a project-specific density can be used instead.

Loads that are not floor-area based (the special equipment entries, a specific chiller, a lift, a kitchen) are added as assessment items in watts or amperes, which matches Clause 2.2.2(b) assessment. The calculator then applies an optional overall diversity factor and an optional spare-capacity percentage, both shown as their own lines, and reports the total in both volt-amperes and amperes per phase at 230 V single-phase or 400 V three-phase.

The result is the Appendix C assessed demand. AS/NZS 3000 does not specify a minimum consumer mains current, so check the figure against your distributor's service and installation rules before selecting the cable, and cross-check it against a Table C2 itemised calculation once the equipment schedules are firm.

Reviewed by

Wisam Tozah: Associate Electrical Engineer. B.Eng (Electrical), MIEAust, CPEng, NER, NSW DBP, NSW PRE, APEC, IntPE(Aus). See how these calculations are verified. LinkedIn.

Frequently asked questions

What is the AS/NZS 3000 Table C3 energy demand method?: Table C3 of AS/NZS 3000:2018 Appendix C is titled "Maximum demand: energy demand method for non-domestic installations". Instead of itemising every load, it gives an energy demand density in volt-amperes per square metre for each type of occupancy (a range and a typical average), which is multiplied by the floor area to give the demand. It is the practical method at concept and schematic design, when the floor plate and occupancy are known but the equipment schedules are not.
What VA/m² does Table C3 give for retail shops and warehouses?: Retail shops are tabulated at 40–100 VA/m² (average 70) for light and power, plus 20–40 VA/m² (average 30) for air conditioning. Warehouses are 5–15 VA/m² (average 10) for light and power plus 5 VA/m² for ventilation, with special equipment to be added from actual load details. Light industrial buildings are 10–20 (average 15) light and power, 10–20 (average 15) ventilation and 30–50 (average 40) air conditioning, again with special equipment by load details.
Do I add air conditioning on top of the Table C3 light and power density?: Yes, for the occupancies where Table C3 lists them separately. Offices, retail shops, warehouses and light industrial buildings have a light-and-power density and a separate air-conditioning or ventilation density, and the two are added. Taverns, licensed clubs and theatres are different: they are tabulated as a single total (60–100 and 80–120 VA/m² respectively), so no separate air-conditioning figure is added.
What VA/m² does Table C3 give for an office?: Offices are tabulated at 40–60 VA/m² (average 50) for light and power, with air conditioning added separately according to the system type: cooling 30–40 VA/m² (average 35), reverse cycle 20–30 (25), zonal reheat 40–60 (50) and variable volume 20 VA/m². Start from the average and move within the range: higher for a dense fit-out, lower for sparse occupancy or a low-power-density LED lighting design.
Does Table C3 include EV charging?: Yes, as a separate addition. Table C3 tabulates EV charging at 5–15 VA/m² (average 10) for open-air carparks and 10–30 VA/m² (average 20) for basement carparks, and notes that it should be considered in addition to all other energy demands rather than being included within the carpark density.
Does Table C3 give a higher or lower demand than Table C2?: It depends on the building type and load mix. The Table C3 densities describe a typical fit-out for the occupancy, whereas Table C2 diversifies the loads that are actually scheduled, so the two agree closely on a conventional building and diverge where the fit-out is unusual. Many designers run Table C3 at concept stage and recalculate with Table C2 once the equipment schedules are firm.
Can Table C3 be used as the final design demand?: AS/NZS 3000:2018 Clause 2.2.2 permits maximum demand to be determined by calculation or assessment, and Appendix C (including the Table C3 energy demand method) is the guidance given for that. The practical caution is that a floor-area density cannot see an atypical fit-out, so confirm the result against the actual load schedule and your distributor's service and installation rules before it becomes the design figure.