Guide to smoke alarms: installation, maintenance, testing and laws

man changing smoke alarm battery


Posted March 26, 2024

The best smoke alarms save lives. Learn how to check that your smoke alarms are all working effectively when changing your clocks back as daylight saving time, plus how to maintain your smoke alarms to ensure their effectiveness.

According to the Country Fire Authority (CFA), there are 3,000 house fires in Victoria each year – most of which could be prevented by taking the necessary safety precautions. Smoke alarm checks are vital to saving lives should a fire occur in the home.

The CFA advises that linking the task of changing your clocks for daylight saving time (DST) with checking smoke alarms is the best way for all homeowners, landlords and renters to keep on top of this important safety home maintenance task.

Qualified professionals can install new smoke alarm units, test smoke detectors, replace faulty batteries, inspect battery-operated or hard-wired smoke alarms, fix damaged hard-wired smoke alarms, and assess smoke alarm locations.

Smoke alarms and fire safety guide

What are the leading causes of house fires?

The CFA reports that 15 per cent of fire-related fatalities and serious injuries have occurred from kitchen fires. Leaving your cooking unattended is a leading cause of house fires. Electrical faults in kitchen appliances and keeping flammable items like paper towels or curtains near stoves or other sources of heat can also start kitchen fires. Built-up grease and fat around the stove and range hood can help a kitchen fire travel up into your roof and across the rest of your house.

Lithium-ion battery fires are also on the rise, with more than 450 fires across Australia being linked to lithium-ion batteries over the past 18 months. Many cordless appliances and electronics now use rechargeable lithium-ion batteries, which can potentially catch fire if the battery is damaged, overcharged, or exposed to extreme heat sources.

Powerboards are another house fire culprit. They should only be used as a temporary solution rather than a permanent fixture, and should never have more than one device per outlet plugged in. Using double adapters, 'daisy-chaining' extra powerboards or plugging in high-powered appliances like heaters can cause a powerboard to overheat.

Heating appliances should be kept well away from flammable items like bedding, curtains and clothing. Always turn off portable heaters when you go to sleep or leave the house. Keep any heating appliances regularly maintained to reduce the risk of an electrical fault.

Finally, barbecues are another common cause of household fires. Make sure you carry out a thorough safety check before you fire up your grill or barbeque.


man testing smoke alarm

You should regularly clean and test smoke alarms. Image: RACV

What are the laws on smoke alarms?

Victorian law states that houses built before 1 August 1997 only require standalone, battery-powered smoke alarms.

All homes, units, flats and townhouses built after 1 August 1997 must have smoke alarms installed that comply with Australian Standards AS3786 and are connected to 240 volt mains power. Smoke alarms must also have a backup battery installed in case of a power outage.

The minimum legal smoke alarm requirement is that you have smoke alarms located between each bedroom area and the remainder of the home. This means that, for most homes, a smoke alarm must be placed in the hallway outside bedrooms.

All new homes, and those undergoing significant renovation, after 1 May 2014 must also use interconnected smoke alarms if there is a need for multiple smoke alarms.

Smoke alarms and rental properties

For rental agreements entered into after 29 March 2021, rental providers must ensure that smoke alarms are correctly installed and in working order. They must ensure that smoke alarms are tested at least once every 12 months, and have their batteries replaced as required. Smoke alarms that are not working are considered an urgent repair.

Landlords must ensure their property meets the legal standards for house safety, so annual smoke alarm checks should be conducted in rental properties. A Smoke Alarm Safety Check can be added to a Rental Property Inspection. The check includes an assessment of all smoke alarms' positioning, sound and safety, plus smoke spray tests and battery replacement if required.

What are interconnected smoke alarms?

Interconnected smoke alarms ensure that every smoke alarm in the house activates as soon as one smoke alarm senses smoke. This alerts household members in different parts of the home to the potential danger.

The CFA reports that studies show 85 percent of children do not wake to the sound of a smoke alarm. Interconnected smoke alarms ensure that the alarm in or near the parents' bedroom will also sound if the alarm in the child's bedroom activates. This is just one example of how important it is to have interconnected smoke alarms.

Although the law states that only homes built or significantly renovated after May 2014 require interconnected alarms, the CFA recommends that all smoke alarms should be interconnected.

Wireless interconnected smoke alarms use wireless radio frequency (RF) transmissions to connect to each other, much like paired Bluetooth devices. Some wireless smoke alarms even connect to a mobile phone app, which lets you know when and where the smoke alarm has been activated and allows you to remotely silence the alarm if you just burnt your toast.


man installing smoke alarm

Only qualified professionals should install smoke alarms. Image: RACV

Where should smoke alarms be installed?

The CFA recommends installing a smoke alarm on each level of your house, with one smoke alarm in each bedroom and living area. Installing smoke alarms in hallways and stairs between floors increases the likelihood that a fire will be detected quickly.

The CFA reports that most fatal fires start in the lounge room or bedroom, with most fatal fires starting between the sleeping hours of 8pm and 8am. When a fire starts, you may have less than three minutes to wake up and get out of the house - but when you're asleep, you lose your sense of smell and are unable to sense smoke. Recent research also shows that a hallway smoke alarm may not activate if a fire starts in the bedroom in time to allow people to get out. That's why the CFA recommends installing smoke alarms inside bedrooms too.

Follow the manufacturer's instructions when installing smoke alarms. Here are the general installation recommendations:

  • Smoke alarms installed on the ceiling should be located in the centre of the ceiling. It needs to be located at least 300mm from any cornice or wall.
  • If the smoke alarm is installed on the wall, it should be located 300-500mm from the ceiling.
  • If installed on a sloping or cathedral ceiling, the smoke alarm needs to be located 500-1500mm from the highest point.

What are the best smoke alarms?

The CFA recommends installing new smoke alarms with a lithium battery that has a 10-year lifespan for the highest level of security.

These new alarms also ensure you’re not interrupted every year with a beeping smoke alarm that needs a battery change.


person pressing smoke alarm test button

Press the smoke alarm's test button monthly - it should beep to indicate that the alarm is working. Image: Getty

How to check and maintain smoke alarms

Only working smoke alarms save lives.

The CFA reports that only 45 per cent of properties attended by fire services had smoke alarms. Of those smoke alarms, 31 per cent were not working.

Here's how to keep your smoke alarms well-maintained.

Regularly clean all smoke alarms

Dust build-up, dead insects, and other substances can prevent smoke alarms from working effectively. Once a month, dust your smoke alarms with a vacuum cleaner brush to keep them clean and clear of debris.

Test the smoke alarm each month

The CFA recommends testing every smoke alarm in your home each month. Simply press the smoke alarm's test button to make sure it beeps. If the smoke alarm doesn't beep, or sounds laboured, then its battery may need changing.

Replace the smoke alarm battery

The CFA recommends that all smoke alarms in the home should be powered by a 10-year lithium battery. Every 10 years, the battery (and backup battery, if you have a hard-wired smoke alarm) should be replaced.

If you have a 9-volt battery in your smoke alarm, the battery will need replacing every year.

If you’re unsure of testing or replacing your smoke alarm batteries yourself, you can get a qualified professional to assist.

Replace the smoke alarm unit every 10 years

Smoke alarm units should be replaced every 10 years by a licensed electrician.

If you aren't sure whether it's been 10 years, check the use-by date: most smoke alarms have one printed on them.

The unit should also be changed if the unit is yellowing, if it still continually chirps or beeps after a battery change, or if it keeps activating for no reason.


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RACV Trades is a trading name of RACV's trade partner, Club Home Response Pty Ltd (Victorian registered domestic building practitioner number CDB-U 100178). All works are performed or arranged by Club Home Response Pty Ltd. trading as RACV Trades.