Short answer: for almost every modern Brisbane home, wireless beats hardwired — faster to install, cleaner finish, no destroyed plaster, easier to expand later, and the battery and signal reliability of current-gen Ajax wireless is on par with anything cabled. The exceptions are: large commercial sites where 24/7 mains-powered devices are mandated, sites with severe RF interference (e.g. industrial environments next to heavy machinery), or projects where the alarm cable can ride along with active CCTV cabling work happening anyway. Mr Secured installs both, but 95%+ of our 2026 residential jobs are wireless Ajax.
What’s the actual difference?
Hardwired alarms run a dedicated low-voltage cable from each sensor (door reed, motion detector, glass break) back to a central control panel. Power and signal both travel down the cable. The panel sits in a cupboard or garage, hardwired to mains with a backup battery. Adding a sensor means pulling new cable through walls or ceilings.
Wireless alarms use battery-powered sensors that radio back to a central hub via an encrypted wireless protocol (Ajax Jeweller, on the 868 MHz band in Australia). Sensors run 5-7 years on a single battery. The hub plugs into mains plus ethernet plus an internal 4G SIM, with its own backup battery. Adding a sensor means peeling off the back, sticking it on the wall, and pairing it through the app — no cable, no patching, no plaster damage.
What changes between the two
| Dimension | Hardwired | Wireless (Ajax) |
|---|---|---|
| Install time (typical 4-bed house) | 2-3 days, with cable runs through ceilings/walls | 1 day, no cabling work |
| Patching/painting required | Yes — usually $300-$800 in painter callbacks | None |
| Cost (typical 4-bed house, 8 sensors) | $4,500-$7,000 | $3,500-$5,000 |
| Sensor battery life | N/A — mains-powered through cable | 5-7 years on standard sensors, 4-5 on motion + camera sensors |
| Adding new sensors later | Cable run + repatching, $200-$400 per sensor | Stick + pair, $80-$150 per sensor |
| Hub failure mode | Loses comms; sensors dead until panel replaced | Loses comms; sensors keep recording locally and re-sync when hub returns |
| Tamper detection | Cable-cut detection on each loop | Per-device tamper switch + RF jamming detection |
| Lightning / surge risk | Higher — every cable is a path for surge | Lower — only the hub is on mains |
| App control / phone alerts | Most retrofit kits, varies | Native, modern, supports up to 50 user phones |
| Reliability over 7 years | Excellent if cabling installed clean; bad if cabling chafes against beams | Excellent — Ajax has industrial-grade RF design |
Where wireless used to lose, and why it doesn’t anymore
The old objections to wireless alarms — and why they no longer apply to Ajax-class systems:
“Batteries die at the wrong moment.” Old wireless alarms used 9V or AA batteries that lasted 12-18 months. Ajax uses CR123A or AA batteries spec’d for 5-7 years, and the system reports each sensor’s exact battery percentage daily through the app. You replace batteries when the app tells you to — not after the alarm has failed silently.
“Wireless can be jammed.” Ajax detects RF jamming (a continuous noise on the alarm band) within seconds and triggers the alarm in jammed state. Real-world residential jamming is vanishingly rare in Brisbane.
Get a fixed-price wireless alarm quote: mrsecured.com.au/contact or call 0490 130 339. See the full Ajax range.
