Buying and Installing Smoke Alarms

Fire and Emergency New Zealand

Buying and Installing Smoke Alarms

Buying a smoke alarm

Hard-wired or battery operated?

Wherever possible, we recommend hard-wired and interconnected smoke alarms are installed.

If your alarms cannot be hard-wired, we recommend long-life photoelectric smoke alarms that rely on long-life lithium batteries. Inbuilt long-life lithium batteries last as long as the smoke alarm so you don’t need to worry about replacing them every year – you simply replace the entire smoke alarm unit once every 10 years.

There are several specialised smoke alarms available for people who are deaf or hearing impaired. Find out more here.

Photoelectric vs. Ionisation?

Smoke alarms use either photoelectric or ionisation sensors to detect smoke. Some have both types of sensor (“dual” models).

Fire and Emergency New Zealand recommends long-life photoelectric smoke alarms.

Photoelectric smoke alarms are typically more effective at detecting slow smouldering fires, which burn for hours before bursting into flame. Ionisation smoke alarms are typically more effective at detecting fast flaming fires, which burn and spread quickly.

Unsure which type you have? Ionisation models require a tiny amount of radioactive material to make them work. You can identify one by the radiation symbol found on the plastic body.

The Residential Tenancy Act requires landlords to install and replace expired smoke alarms with long-life battery photoelectric smoke alarms. Further information can be found at:

Do not install a smoke alarm in your kitchen. Smoke and heat from cooking and the toaster can set off the alarm. Don’t install them in the bathroom, laundry or garage either. You can buy heat alarms for these areas.

How many do I need?

Smoke alarms cannot detect smoke through a closed door. Therefore, we recommend installing a smoke alarm in every bedroom, hallway and living area.

Please note: The New Zealand Building Code requires an approved smoke alarm to be fitted in every escape route (hallway) and within three metres of every sleeping space (bedroom) door.

Smoke alarm floor plan

Smoke alarms are available for purchase at most major supermarkets and hardware stores across New Zealand. Prices range from $6 - $75

Safe disposal of smoke alarms

When your smoke alarms fail, you can put them out in your normal rubbish disposal.

Further public advice is available at