Whilst battery powered smoke alarms* are easy for homeowners to DIY install, there are certain situations where they are not permitted by law and a hard wired smoke alarm must be used. Prior to installing any type of smoke alarm, it is important to understand their differences and when each can be used.
What is a hard wired smoke alarm?
A hard wired smoke alarm is an alarm which is hard wired to a domestic dwelling’s 240 volt electricity supply. As electrical wiring is necessary, hard wired smoke alarms cannot be DIY installed and should always be installed by a trade qualified Electrician. Hard wired smoke alarms have an internal battery back-up which allows for continuous power supply should the household mains electricity be temporarily disrupted (i.e. power black-out during a thunder storm). When there is more than one, hard wired smoke alarms must be interconnected to each other – this can be achieved in two ways – either by running physical cabling in the ceiling space in-between each alarm, or wirelessly using a radio frequency (RF) transmitter.
When must I install a hard wired smoke alarm?
There are 3 situations in Queensland when it is a statutory requirement for 240 volt hard wired smoke alarms to be installed.
1) If you are constructing a new home
If you are constructing a new home then hard wired smoke alarms are required as part of the building approval process – Queensland’s Building Regulations 2021 (part 4) and the National Construction Code (NCC 2019 volume 2 part 3.7.5) detail minimum necessary building standards, including those for fire safety and smoke alarms.
Queensland’s Building Regulations 2021 state that when constructing a new home, the smoke alarms must be hardwired to the domestic dwelling’s electricity supply; and must be interconnected to every other smoke alarm installed in the dwelling.
2) If you are performing a substantial renovation
Division 5A (section 104RBA) of the QLD Fire and Emergency Services Act 1990 states that hard wired smoke alarms must be installed when a substantial renovation is being performed to an existing dwelling.
A ‘substantial renovation’ is defined as building work carried out under a building development approval, or the total building works equaling 50 per cent of the dwelling over three years.
3) If you are replacing an existing hard wired smoke alarm
Division 5A (section 104RC) of the QLD Fire and Emergency Services Act 1990 states that if the smoke alarm being replaced was hardwired to the domestic dwelling’s electricity supply, the replacement smoke alarm must also be hardwired to the dwelling’s electricity supply. A smoke alarm must be replaced if it fails to operate or is older than 10 years from manufacture date (manufacture date is printed on the rear of the alarm).
What if I don’t need to replace my existing hard wired smoke alarms? Can I leave them in place and install additional battery powered alarms in all the required locations and be compliant?
This is a common question. Provided the existing hard wired smoke alarms work and their manufacture date is less than 10 years they do not need to be replaced.
Battery powered interconnected photoelectric smoke alarms can then be installed in all prescribed locations as required by QLD law. The position of the Queensland Fire and Emergency Services (QFES) is that the existing hard wired smoke alarms are then considered to be extra additional alarms, and do not need to be interconnected to the newly installed battery powered smoke alarms. Compliance is achieved.
Replacing and installing new hard wired smoke alarms
Red smoke alarms are a 100% Australian owned company that manufacture quality 240 volt hard wired smoke alarms for those people that do need to replace or install hard wired smoke alarms. Aside from the 10 year product warranty, what makes the Red hard wired smoke alarm so good is that it comes in two versions depending on the preferred type of battery back-up. The Red hard wired smoke alarm (model R240RC) comes with an in-built rechargeable 10 year lithium battery (never needs replacing) whereas the Red hard wired smoke alarm (model R240) has a user replaceable 9 volt back-up battery. The choice is yours.
Another great feature of Red hard wired smoke detectors is how they can be interconnected with one another. There are two options. First, each Red hard wired smoke detector can be physically interconnected by having an electrician run cabling from alarm to alarm in your ceiling space. If this is too cost prohibitive and/or difficult to do, the second option is to interconnect the hard wired smoke alarms using wireless radio frequency (RF) technology. This is achieved by installing a small Red hard wired base beneath each hard wired smoke alarm. The base acts as an RF transmitter and allows the hard wired smoke alarms to become interconnected and ‘talk’ to one another without the need to run physical cabling from alarm to alarm. An added benefit of the Red hard wired base is that it also allows the Red hard wired smoke alarm to talk to not only other Red hard wired smoke alarms, but also to the Red remote control and other Red battery powered smoke alarms and Red heat alarms – extremely versatile.
Summary
This article has demonstrated the 3 criteria where hard wired smoke alarms must be installed as per QLD legislation. In all other scenarios it is acceptable to use battery powered smoke alarms to achieve compliance.
Before purchasing new replacement smoke alarms for your home be sure to check if your existing smoke alarms are hard wired, or not. Doing this may save complications later, if for example you purchased battery powered smoke alarms, only to discover that what you really needed are hard wired smoke alarms.
* A ‘battery powered’ smoke alarm is a smoke alarm powered by a non-removable 10-year battery compliant with Australian Standard 3786:2014.
Referenced legislation:
QLD Building Regulations 2021 (part 4)
National Construction Code (NCC) 2019 volume 2 part 3.7.5