Download the PDF file: Smoke Alarm Legislation

Regulation 76B of the Regulations under the Development Act, 1993 requires that smoke alarms complying with Australian Standard 3786 be fitted to all “Class 1 and 2 buildings.” (Compliance with Australian Standard 3786 will be shown on the smoke alarm packaging.)

“Class 1 and 2 buildings” means:

  • Any single dwelling including detached houses or attached houses such as row houses, terrace houses, town houses, villa units, etc.
  • A boarding house, guest house, hostel or the like with a total floor area not exceeding 300m2 and in which not more than 12 persons would ordinarily be resident. Note: Larger buildings of these types will require a commercial type fire alarm system.
  • Any building containing two or more sole-occupancy units each being a separate dwelling (i.e. flats, motel units, apartments and the like) where the building is not required to be fitted with a commercial type fire alarm system. The Building Code of Australia also requires domestic smoke alarms complying with Australian Standard 3786 in Class 3 and 4 buildings.
  • Class 3 building means a residential building, other than a Class 1 or 2 building, which is a common place of long term or transient living for a number of unrelated persons (maximum 20 persons 2 storeys or less). Example: boarding-house, hostel, backpackers’ accommodation or residential part of a hotel, motel, school or detention centre.
  • Class 4 means a dwelling in a building not purpose built for accommodation. Example: A flat over a shop.

Building Approval On Or After 1 January 1995

Since 1 January 1995, smoke alarms have been required in all new homes in South Australia. These alarms must be hard-wired to the 240 volt mains power supply unless the dwelling is not connected to such a supply.

They should also be fitted with a back-up battery to provide power in case of a mains power supply failure.

In dwellings not connected to mains power, smoke alarms powered by 10 year life, non-replaceable, non-removable, permanently connected batteries may be installed.

Existing Buildings

As a minimum requirement all homes where building approval was granted before 1 January 1995 are required to be fitted with a smoke alarm powered by a replaceable battery subject to the following change of ownership conditions.

Change of ownership on or after 1 February 1998 From 1 February 1998, if there is a change of ownership of the land on which any building covered by this legislation is built, the new owner must, within 6 months of title transfer, install smoke alarms either:

  • hard-wired to the 240 volt household power supply (unless the dwelling is not connected to such a supply); or
  • powered by 10 year life, non-replaceable, non-removable, permanently connected batteries.

Home owners were required to comply with the smoke alarm legislation for existing buildings by 1 January 2000.

Interconnection Of Alarms

  • From 1 May 2014, smoke alarms have been required to be interconnected in all new class 1 dwellings, within sole-occupancy units of class 2 and 3 buildings and in class 4 parts of buildings. (Class 4 is a single dwelling in an office building, retail building, storage building, manufacturing building or public building.)
  • In existing buildings (i.e. those approved before 1 May 2014) any extension or addition (approved from 1 May 2014) which requires more than one smoke alarm must have those alarms interconnected however there is not a requirement to interconnect to alarms in the existing building.
  • Smoke alarms in subsequent extensions will be required to interconnect to any alarms in extensions approved after 1 May 2014.

How Many Smoke Alarms And Where?

The Development Regulations require that one or more smoke alarms must be installed in every dwelling in locations that will provide reasonable warning to occupants of sleeping areas so that they may safely evacuate in the event of a fire.

For detailed and specific information about smoke alarms please see our Home Fire Safety Fact Sheet “Smoke Alarms”.

For further advice:


Phone: (08) 8204 3611

Country Callers: 1300 737 637

Want more information on which is the right smoke alarm for your home?

Look at our Smoke Alarm Quick Guide Fact Sheet