Energy efficient home design

Water heater requirements

South Australia has water heater requirements that may affect the type of water heater you can install in a home. The requirements may also affect the water efficiency of showers serviced by the water heater. The requirements are designed to improve the energy efficiency of homes and to lower greenhouse gas emissions.

The requirements mean that for most homes:

  • low greenhouse gas emission (low emission) water heaters must be installed, such as high efficiency gas, solar or electric heat pump water heaters
  • shower outlets connected to the installed water heater must have a water efficient shower head or flow restrictor.

The requirements apply to installing new water heaters or replacing old water heaters. Working water heaters do not need to be replaced.

South Australia’s water heater installation requirements have been in place since 2008 and were last reviewed and updated in 2014. The review was informed by technical research and economic modelling, as well as consultation with a range of stakeholders. See the final report: Review of South Australia's Water Heater Installation Requirements (611.5 KB PDF).

For more information about the review, please email

Installing a water heater

Only licensed plumbing contractors or registered plumbing workers can install water heaters. You can check that your installer has a license to do plumbing work using the licensing public register.

The plumber must provide the household and the Office of the Technical Regulator with an electronic Certificate of Compliance (eCOC) for the installation.

Installing an eligible solar or electric heat pump water heater entitles you to small-scale technology certificates (STCs). See Assistance with purchase costs for more information. The number of STCs a system is entitled to create depends on its installation and geographic location. South Australia falls into geographic zones 3 and 4.

Find out which water heater can be installed

Work through the decision maker below to find out which water heater can be installed at a home under the requirements. Visit the Australian Government’s YourHome website if you’d like to know more about different types of water heaters – including electrical, gas and solar hot water systems – and how they work.

If you are repairing an existing water heater, replacing a single faulty component in an existing solar or heat pump water heater, or replacing a water heater under warranty, these requirements don’t apply.

Building classifications

Class 1A: Single detached dwelling or two or more attached dwellings separated by a fire-resistant wall, including a maisonette, row house, townhouse, and single-storey flats or units.

Class 1B: Boarding/guest house or hostel not exceeding 300m2 with no more than 12 residents.

Class 2: Multi-storey building containing two or more sole-occupancy units, where each is a separate dwelling.

The Office of the Technical Regulator may grant exemptions from the requirements on a case-by-case basis where extreme technical difficulties are shown.

Low emission water heaters

Type of water heaterRequirements

Solar - electric boosted


Electric heat pump

You can install a water heater that meets either of these zone requirements anywhere in the state:

220 litres or less rated hot water delivery:

220 litres and less than 400 litres rated hot water delivery:

  • 27 STCs or more for Zone 3
  • 26 STCs or more for Zone 4

400 litres or more and less than 700 litres rated hot water delivery:

  • 38 STCs or more for Zone 3
  • 36 STCs or more for Zone 4

Gas instantaneous or storage - bottled or mains

Must have an energy rating of at least 5 stars.


A gas water heater installed entirely within a fully enclosed roof space, room or attached garage of an established home must have an energy rating of 3 stars or more. This option is not available for water heaters installed as part of building work that requires development approval.

Solar - gas boosted

Eligible for 1 or more STC.

Solar - wood boosted

Any water heater can be installed.

Wood combustion

Any water heater can be installed.

How to determine if an electric boosted solar or heat pump water heater meets the requirements

Find out the number of STCs for a particular brand and model in zones 3 and 4 by:

Check the table above to find out the minimum number of STCs a water heater needs, based on tank volume, in Zone 3 and in Zone 4. You can then compare the water heater's STCs for Zone 3 and for Zone 4 with the minimum requirements. Only one of the two zone requirements needs to be met, ie either the Zone 3 or the Zone 4 requirement. It doesn’t matter which zone the water heater is installed in.


Question: does a 300-litre electric heat pump water heater that is eligible for 26 STCs in Zone 3 and 26 STCs in Zone 4 meet the requirements in this table?

Answer: while the electric heat pump water heater does not meet the Zone 3 requirement (27 STCs or more) it does meet the Zone 4 requirement (26 STCs or more) and can be installed anywhere in the state.

Water flow rate requirements

When installing a new or replacement water heater in a home, any shower outlets connected to the water heater must have a flow rate of nine litres per minute or less. This means you may also need to install water efficient shower heads or flow restrictors that have no less than a three star rating under the water efficiency labelling and standards (WELS) scheme.

If the shower outlets already have three star rated shower heads, no change is needed.

Most new water heaters are compatible with water efficient shower heads, but check with the manufacturer if you are unsure.

Gravity fed water heaters meet the water flow rate requirements, meaning water efficient shower heads or flow restrictor don’t need to be installed.

These water flow rate requirements do not apply if your water heater installation is exempt from the water heater requirements.

Electric storage water heaters supplied by photovoltaic solar

The National Construction Code Volume Three - Plumbing Code of Australia sets energy performance requirements for water heaters in new Class 1 or Class 10 Buildings. The NCC lists several water heater types that are 'deemed to satisfy' these performance requirements, however, Electric Resistive Storage (ERS) water heaters are not included.

Recently, a range of products have been released that use on-site renewable energy — for example, solar photovoltaics (PV) — to supply some or all of the energy for ERS water heaters.

There are two broad types of systems available; those that supply on-site PV energy directly to an electric resistive water heater and those that divert excess on-site PV from being exported to the grid to an electric resistive water heater.

A Verification Method (72.3 KB PDF) has been prepared to demonstrate compliance of these systems with Performance Requirement BP2.8(b) of the NCC Volume 3. If you are considering one of these systems for your new home, seek confirmation from your installer that the system complies with this verification method.

Plumbing contractors who install electric resistive water heaters on new homes supplied by PV panels must certify compliance with this verification method on the plumbing Certificate of Compliance (CoC) which is provided to the property owner and the Office of the Technical Regulator. To include this information on the plumbing CoC, simply click on the 'on-site renewables' box located below the 'heated water energy source' category.

Detailed technical requirements

Details of the requirements for new homes, alterations and additions are in the National Construction Code Volume Three - Plumbing Code of Australia.

Details of requirements for established homes are in the South Australian water heater installation requirements (54.4 KB PDF).

Further assistance

Plumbers can contact the plumbers' water heater information line on 1300 883 019 (Monday to Friday 9.00 am to 5.00 pm) for assistance.

Householders can ask their licensed plumber or building contractor for assistance with code requirements or contact the Energy Advisory Service for more information.

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Page last updated 4 April 2019

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