---
title: "Table C3 Energy Demand Calculator: Maximum Demand from Floor Area (VA/m²) to AS/NZS 3000:2018"
url: "https://scaleset.com.au/calculator/c3"
description: "Free AS/NZS 3000 Table C3 energy demand calculator: maximum demand from floor area in VA/m² for offices, retail, warehouses, carparks and more."
updated: "2026-10-13"
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)"
author: "Wisam Tozah (B.Eng (Electrical), MIEAust, CPEng, NER, NSW DBP, NSW PRE, APEC, IntPE(Aus))"
site: "ScaleSet"
license: "https://scaleset.com.au/terms"
usage: "Cite and link. Do not reproduce or train on this content."
---

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

Source: https://scaleset.com.au/calculator/c3

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. AS/NZS 3000 Table C3 tabulates a VA/m² range and a typical average for each type of occupancy: offices at 40 to 60 VA/m² (average 50) for light and power with air conditioning added separately by system type (cooling 30 to 40, reverse cycle 20 to 30, zonal reheat 40 to 60, variable volume 20); retail shops at 40 to 100 (average 70) plus air conditioning 20 to 40; warehouses at 5 to 15 (average 10) plus ventilation 5; light industrial at 10 to 20 light and power, 10 to 20 ventilation and 30 to 50 air conditioning; carparks at 0 to 10 open air and 10 to 20 basement; taverns and licensed clubs at a total of 60 to 100 (average 80); and theatres at a total of 80 to 120 (average 100). Electric vehicle charging is tabulated separately for carparks (5 to 15 VA/m² open air and 10 to 30 VA/m² basement), and AS/NZS 3000 Table C3 notes it should be considered in addition to all other energy demands. The calculator takes one row per area with two densities, light and power and the air conditioning or ventilation, as AS/NZS 3000 Table C3 lists them, offers a preset for every AS/NZS 3000 Table C3 row at its average, 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 PDF report (downloading it needs a free account; your own logo and accent colour on it are Pro).

The ScaleSet AS/NZS 3000 Table C3 Calculator applies the AS/NZS 3000:2018 Appendix C Table C3 energy demand method, which assesses the maximum demand of a non-domestic electrical installation from floor area using tabulated volt-amperes per square metre by type of occupancy. It is the floor-area route to a maximum demand figure, used at concept and schematic design, and is distinct from AS/NZS 3000 Table C2, which assesses the same class of installation from an itemised load schedule, and from AS/NZS 3000 Clause 2.2.2(c) measurement, which determines maximum demand from recorded consumption. It is a free browser-based engineering tool.

## Key facts

- AS/NZS 3000 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 to 60 VA/m² (average 50) for light and power, with air conditioning added separately: cooling 30 to 40 (35), reverse cycle 20 to 30 (25), zonal reheat 40 to 60 (50) and variable volume 20 VA/m².
- Retail shops are 40 to 100 VA/m² (average 70) for light and power plus 20 to 40 (30) for air conditioning; warehouses are 5 to 15 (10) plus 5 for ventilation; light industrial is 10 to 20 (15) light and power, 10 to 20 (15) ventilation and 30 to 50 (40) air conditioning.
- Taverns and licensed clubs are tabulated as a total of 60 to 100 VA/m² (average 80), and theatres as a total of 80 to 120 VA/m² (average 100).
- Carparks are 0 to 10 VA/m² (average 5) open air and 10 to 20 (15) basement, and AS/NZS 3000 Table C3 notes that EV charging (5 to 15 VA/m² (10) open air, 10 to 30 (20) basement) is to be considered in addition to all other energy demands.
- Where the occupancy has special equipment, AS/NZS 3000 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 AS/NZS 3000 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 does

- 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 AS/NZS 3000 Table C3 averages for every row: offices by air conditioning system, retail shops, warehouses, light industrial buildings, open-air and basement carparks, EV charging in each, taverns and licensed clubs, and theatres. Every density stays editable for a project-specific figure.
- Keeps light and power and the air conditioning or ventilation as two VA/m² fields per area, as AS/NZS 3000 Table C3 lists them, so both entries stay 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 AS/NZS 3000 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 AS/NZS 3000 Table C3 note that EV charging in carparks (5 to 15 VA/m² open air, 10 to 30 VA/m² basement) is to be considered in addition to all other energy demands: EV charging is its own preset, added as its own area.
- 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 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 AS/NZS 3000 Table C2 calculation (downloading it needs a free account; your own logo and accent colour on it are Pro).
- 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

1. **Set the supply configuration** — Select single-phase (230 V) or three-phase (400 V). AS/NZS 3000 Table C3 gives the demand in volt-amperes, which the calculator converts to amperes per phase.
2. **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.
3. **Apply the AS/NZS 3000 Table C3 densities** — Load the preset for the occupancy or enter the VA/m² figures yourself: light and power in Light & Power, and the air conditioning or ventilation density in Air Con & Ventilation. Where AS/NZS 3000 Table C3 gives one total (carparks, taverns and licensed clubs, theatres) it goes in Light & Power. Use the tabulated average unless the fit-out is known to be at the intensive or sparse end of the range.
4. **Add EV charging separately for carparks** — AS/NZS 3000 Table C3 notes that EV charging is in addition to all other energy demands. For an open-air carpark add 5 to 15 VA/m² (average 10) and for a basement carpark 10 to 30 VA/m² (average 20) as its own area row with the EV charging preset, so it shows on its own line.
5. **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.
6. **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 AS/NZS 3000 Table C3 total. Both appear as separate lines so the raw AS/NZS 3000 Appendix C figure stays visible.
7. **Review the total and export the report** — Check the per-area breakdown, compare the result against your distributor's requirements and against an AS/NZS 3000 Table C2 itemised calculation once the equipment schedules firm up, then export the PDF report for the design record (a free account to download).

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

### What the AS/NZS 3000 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 an AS/NZS 3000 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 to 60 VA/m², average 50. Air conditioning is tabulated separately by system type (cooling 30 to 40 (average 35), reverse cycle 20 to 30 (25), zonal reheat 40 to 60 (50) and variable volume 20 VA/m²), and is added to the light and power figure.

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

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

AS/NZS 3000 Table C3 carries an explicit note on electric vehicle charging: the EV charging densities (5 to 15 VA/m² (average 10) for open-air carparks and 10 to 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 ScaleSet Table C3 calculator takes one row per area: a description, the floor area in square metres, and two VA/m² densities (light and power, and air conditioning or ventilation), the two entries AS/NZS 3000 Table C3 lists, both shown in the breakdown. A preset for every AS/NZS 3000 Table C3 row (offices by air conditioning system, retail shops, warehouses, light industrial, open-air and basement carparks, EV charging, taverns and licensed clubs, theatres) loads the table’s averages, 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 AS/NZS 3000 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 AS/NZS 3000 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 an AS/NZS 3000 Table C2 itemised calculation once the equipment schedules are firm.

## Key terms

- **AS/NZS 3000 Table C3** — The AS/NZS 3000:2018 Appendix C table giving the energy demand method: maximum demand for a non-domestic installation assessed from floor area in volt-amperes per square metre, by occupancy type.
- **Energy demand method** — Assessing maximum demand from a load density and a floor area rather than from an itemised equipment schedule. It is the method available at early design, before the equipment is known.
- **VA/m²** — Volt-amperes per square metre: the load density AS/NZS 3000 Table C3 tabulates for each occupancy. Multiplying it by the floor area gives the apparent power, which converts to a current per phase.
- **Typical average** — The single figure AS/NZS 3000 Table C3 gives alongside each range, for use when nothing about the occupancy suggests the high or low end of the range applies.
- **Occupancy type** — The building use AS/NZS 3000 Table C3 keys its densities to (office, retail shop, warehouse, light industrial, carpark, tavern, theatre). It determines both the light-and-power density and how air conditioning is added.
- **Gross floor area** — The area the VA/m² density is applied to. Getting the boundary right matters: including or excluding plant rooms, carparks and voids changes the demand proportionally.

## Frequently asked questions

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

Table C3 of AS/NZS 3000:2018 Appendix C, "Maximum demand: energy demand method for non-domestic installations", assesses maximum demand from floor area: 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. AS/NZS 3000 Paragraph C2.4.3 presents it as the alternative calculation method for commercial and light-industrial applications. 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 AS/NZS 3000 Table C3 give for retail shops, warehouses and light industrial?

Retail shops are 40 to 100 VA/m² (average 70) for light and power plus 20 to 40 VA/m² (average 30) for air conditioning. Warehouses are 5 to 15 VA/m² (average 10) for light and power plus 5 VA/m² for ventilation, with special equipment added from its actual load details. Light industrial buildings are 10 to 20 (average 15) for light and power, 10 to 20 (average 15) for ventilation and 30 to 50 (average 40) for air conditioning, again with special equipment by load details. In the calculator, special equipment goes under By Assessment in watts or amps.

### Do I add air conditioning on top of the AS/NZS 3000 Table C3 light and power density?

Yes, for the occupancies where AS/NZS 3000 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 and licensed clubs (60 to 100 VA/m², average 80) and theatres (80 to 120 VA/m², average 100) are tabulated as a single total, so no separate air-conditioning figure is added.

### What VA/m² does AS/NZS 3000 Table C3 give for an office?

Offices are tabulated at 40 to 60 VA/m² (average 50) for light and power, with air conditioning added separately by system type: cooling 30 to 40 VA/m² (average 35), reverse cycle 20 to 30 (25), zonal reheat 40 to 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 AS/NZS 3000 Table C3 give a higher or lower demand than Table C2?

Neither, consistently. AS/NZS 3000 Table C3 densities describe a typical fit-out for the occupancy, and AS/NZS 3000 Paragraph C2.4.3.1 notes they depend on the climate, occupancy hours and levels, energy management and how evenly the equipment is spread, while AS/NZS 3000 Table C2 diversifies the loads actually scheduled. A building with unusual plant can land well above its AS/NZS 3000 Table C3 figure, and a sparse fit-out below it. Run AS/NZS 3000 Table C3 at concept stage and recalculate with Table C2 once the equipment schedules are firm.

### Can AS/NZS 3000 Table C3 be used as the final design maximum demand?

Yes. AS/NZS 3000 Table C3 is one of the Appendix C calculation methods that Clause 2.2.2(a) points to, so an AS/NZS 3000 Table C3 figure is a valid maximum demand. A floor-area density cannot see an atypical fit-out, though, so check it against the actual load schedule, add any special equipment from its load details, and confirm it with the distributor's service and installation rules before it becomes the design figure.

### How do I convert an AS/NZS 3000 Table C3 VA/m² figure into amps?

Multiply each density by its floor area to get VA, add the areas, then divide by √3 × 400 V for the current per phase on a three-phase supply, or by 230 V on single-phase. AS/NZS 3000 Paragraph C2.4.3.2 works a 1500 m² office at 50 VA/m² for light and power plus 50 VA/m² for zonal reheat air conditioning: 150 kVA, about 217 A per phase at 230/400 V. A 2000 m² office at 50 VA/m² plus 35 VA/m² for cooling is 170 kVA, or 245 A. The calculator does the conversion and shows the total in kVA and in amps per phase.

### What VA/m² does AS/NZS 3000 Table C3 give for carparks and EV charging?

An open-air carpark is 0 to 10 VA/m² (average 5) and a basement carpark 10 to 20 VA/m² (average 15). EV charging is a separate row: 5 to 15 VA/m² (average 10) open air and 10 to 30 VA/m² (average 20) in a basement. The note to AS/NZS 3000 Table C3 says EV charging is considered in addition to all other energy demands, so a basement carpark with charging is 15 + 20 = 35 VA/m² at the averages. In the calculator, enter the EV density as its own area row so it shows on its own line.

## Related ScaleSet pages

- [Maximum Demand Hub](https://scaleset.com.au/calculator/max-demand)
- [AS/NZS 3000 Table C1 Calculator](https://scaleset.com.au/calculator/c1)
- [AS/NZS 3000 Table C2 Calculator](https://scaleset.com.au/calculator/c2)
- [Cable Size Calculator](https://scaleset.com.au/calculator/cable-selection)
- [Switchboard Sizing Calculator](https://scaleset.com.au/calculator/switchboard-sizing)
- [Voltage Drop Calculator](https://scaleset.com.au/calculator/voltage-drop)
- [Conduit Sizing Calculator](https://scaleset.com.au/calculator/conduit-sizing)
- [Design Guides](https://scaleset.com.au/design-guide)
- [Calculation Verification](https://scaleset.com.au/verification)

## About this page

Methods built and reviewed by Wisam Tozah (CPEng, NER, MIEAust), Sydney, Australia. How the methods are tested and reviewed: https://scaleset.com.au/verification. ScaleSet is a design aid: your inputs and results are not reviewed or certified, and responsibility for the design stays with the engineer who issues it. Profile: https://scaleset.com.au/creator.

Usage: this page may be read, indexed, retrieved and cited, including as grounding for an AI answer, with attribution to ScaleSet and a link to https://scaleset.com.au/calculator/c3. Reproducing it, training a model on it, or using it to build a derivative or competing site is not licensed. Terms: https://scaleset.com.au/terms. Machine-readable policy: https://scaleset.com.au/ai-usage-policy.json

Site index for assistants: https://scaleset.com.au/llms.txt — full content: https://scaleset.com.au/llms-full.txt