

Dead air space is invisible, but it can stop smoke alarms from doing their job. Identifying the best position for placing smoke alarms is crucial for safety, as well as complying with legislation.
Have you heard of dead air space?
Many people don’t know how to spot it, or how to stop it from interfering with smoke alarms.
Dead air space is an unventilated space where air doesn’t circulate. It often occurs where corners meet, like in the apex of a cathedral ceiling, in between exposed floor joists in the ceiling or where the ceiling meets the wall. Air can get trapped here in pockets, so that no new air flows in or out of the space.
What does this mean for smoke alarms?
When a room fills with smoke, the smoke won’t penetrate dead air spaces because the trapped air and lack of circulation keeps the smoke out of that pocket. The smoke will just roll along the path of least resistance, past the dead air space.
If a smoke alarm happens to be mounted in a dead air space, it won’t detect smoke properly because a pocket of air is keeping the smoke away from the alarm’s sensors. The room could be filling with smoke while the smoke detector is effectively trapped in a protective bubble of dead air, preventing it from doing its job!
Smoke alarm placement is complicated – for a reason!
Since most fire fatalities occur when people are sleeping, it’s crucial that smoke alarms are placed to alert people to the presence of smoke with plenty of time to wake up and get out of the building.
The location of smoke alarms can have a significant impact on their performance and ultimately on the safety of the occupants in case of a fire.
Regulations around the number, type and placement of smoke alarms are very specific. It can be frustrating for property owners, but the regulations have been designed that way for good reasons! There are a lot of factors when it comes to safety.
One of the considerations for smoke alarm placement is the avoidance of dead air space. You can’t see dead air space, but a properly trained technician can pick the best placement for smoke alarms to ensure maximum performance in an emergency.
It’s not simple to place smoke alarms correctly, but it’s important to get it right.
The rules for the installation of smoke alarms depend on the building’s use, its size and its layout. The legislation requirements in each state provide a detailed guide, but every building is a little different.
Dead air space is one of the many considerations that an expert technician will take into account when choosing the right positions for smoke alarms in accordance with the guidelines in the legislation.
There’s an art to meeting all the legislative requirements and identifying the best locations for smoke alarms based on the features of the individual building. That’s why it’s important to get somebody with the right expertise to install smoke alarms and perform regular inspections.
A simple solution
Detector Inspector’s trained technicians have expertise in state specific legislation, smoke alarm technology and safety issues. You can rest assured they know what they’re doing!
During an initial smoke alarm safety service
- Our technician might identify that a hardwired smoke alarm is located in a dead air space.
- We send out a quote and seek approval to reposition the alarm.
- If approved, a qualified electrician will be booked to reposition it.
Then Detector Inspector maintains compliance year after year as the legislation changes. Our customisable, automated service system means there’s virtually no admin and no hassle for property managers, owners or tenants.
Enrol your properties in our smoke alarm safety program and never worry about compliance again.
Dead air space can be deadly. It’s not worth the risk!
Before 2019, The Building Code of Australia recommended repositioning any smoke alarm mounted in dead air space, so if the property was built prior to 2019 we’re still able to issue a certificate of compliance if the owner chooses not to go ahead. However, for properties built since 2019, it has become mandatory.
To be safe, we strongly recommend repositioning all smoke alarms to get them clear of dead air space. This will help ensure that all smoke alarms are operating properly and detecting smoke efficiently in case of an emergency.
If the worst happens and a smoke alarm fails to operate when occupants are sleeping, it might be too late.
Plus, there could be liability issues if damage or death occurs from a fire where the owner was informed about dead air space and chose not to reposition a smoke alarm.
For peace of mind on complicated issues like smoke alarm placement, put your properties in the hands of a provider with the right expertise.