Health and Safety

Taking care with materials, equipment and work procedures and dealing with hazards.

Smoke alarms

People who are sleeping do not smell smoke and are unlikely to wake up during a fire. The most effective way to ensure house occupants wake up and get to safety is to install smoke alarms.

On this page:

  • legal requirements
  • how many alarms?
  • where to locate alarms
  • maintenance
  • smoke alarms for the hearing impaired.

Legal requirements

Smoke alarms are a requirement under New Zealand Building Code clause F7 Warning systems. This applies to new homes and all existing homes undergoing building work.

Acceptable Solution F7/AS1 requires Type 1 smoke alarms, which must have:

  • a hush button to silence the alarm for at least 60 seconds  
  • a test button
  • a sound level that complies with NZS 4514:2021 Interconnected smoke alarms for houses – not less than 75 dBA at the sleeping position and not more than 100 dBA at 1.8 m height. (The standard can be downloaded for free.)

On floors with bedrooms the smoke alarms must be located either in every sleeping space or within 3.0 m of every sleeping space door. In this case, the smoke alarms must be audible to sleeping occupants on the other side of the closed doors.

In multi-storey homes there must be at least one smoke alarm on each level, however having an alarm in each sleeping space is considered preferable.

Although there are several types of alarms that can be used to comply with Building Code requirements, Fire and Emergency New Zealand recommends hard-wired alarms or photoelectric alarms with batteries that last up to 10 years. Installing or replacing a hard-wired alarm must be done by a licensed electrician.

With interconnected alarms, when one smoke alarm detects fire smoke, all alarms will sound. Some models connect wirelessly. Interconnected smoke alarms are not a Building Code requirement yet, but this is going to be adopted as the minimum fire safety system in household units in November 2023 with a 12-month transition period ending in November 2024. The amended acceptable solutions will cite NZS 4514: 2021 Interconnected smoke alarms for houses for their installation.

Some of the key points of the standard include:

  • The alarms must be in all bedrooms, living spaces, hallways and landings, and on each level of a multi-level home.
  • Where a kitchen is separated from living spaces and hallways by closable doors, an alarm suitable for kitchens (which may be a heat alarm) must be installed in the kitchen.
  • Where they are required, alarms must be mounted within 10 m of each other in any direction.
  • The alarms can be hard-wired or operated with a long-life (minimum 10-year) sealed and non-removable battery. Where hard wired they must be tested and certified by a licensed electrical worker.
  • The interconnection between the alarms can be wired or wireless and hard-wired alarms can be incorporated into a security system.

Under the Residential Tenancies (Smoke Alarms and Insulation) Regulations 2016 all rental homes must have smoke alarms:

  • The alarms must be either hard wired or photoelectric battery alarms with a battery life of at least 8 years.
  • If alarms have a battery, it is the tenant’s responsibility to replace the battery when it is worn out.
  • There must be at least one smoke alarm installed in the sleeping space or within 3 metres of the entrance to the sleeping space.
  • There must be an alarm on each floor where there is a habitable space however having an alarm within each sleeping space is preferable.

How many alarms?

Fire and Emergency New Zealand recommends installing an alarm in each sleeping and living space and interconnecting them – a sensible approach to ensure full compliance with F7/AS1. New alarms are available that are smaller and more discreet with longer battery life than the older models.

Where to locate alarms

Alarms should ideally be installed on the ceiling, at least 200 mm from a wall or a ceiling beam to avoid dead air space. With sloping ceilings the alarm should be 200–500 mm from the apex.

An alternative (but not preferred) position is high on a wall, at least 100 mm from the ceiling and 600 mm from corners to avoid dead air pockets.

To reduce the risk of false alarms or faults, do not install:

  • in a kitchen, garage or bathroom
  • near a heat source such as a heat pump or solid fuel burner
  • in damp or draughty areas.

Smoke alarms are a legal requirement in all sleepouts.

Separated sleeping areas 
Separated sleeping areas

At least two smoke alarms are needed where there are two sleeping areas separated by the living area.

Placement of smoke alarms 
Placement of smoke alarms

At the very least, a smoke alarm should be placed between the sleeping area and living areas.

More than one storey 
More than one storey

Where a house has more than one storey there should be at least one smoke alarm on each level.


Vacuum over smoke alarms to avoid dust build-up, and test with the test button monthly. The smoke detection element can be tested annually with an incense stick. Battery alarms should be replaced every 10 years.

Smoke alarms for the hearing impaired

Significant numbers of people, especially among those over 70, have some form of hearing loss. Smoke alarms that warn purely through a high-pitched sound may not be enough for them, especially overnight when people take out their hearing aids. A specialised smoke alarm system may be required with an extra-loud and/or lower-pitch alarm sound, flashing strobe lights or vibrating under-pillow devices.



Updated: 27 July 2023