By Michael Turner
False alarms are the most common frustration with home security systems. Understanding what happens when your alarm triggers accidentally — and how to prevent it — helps you get the most from your system without unnecessary stress or consequences.
What Triggers False Alarms
The most common causes of accidental alarm triggers are: pets activating PIR motion detectors, forgetting to disarm before the entry delay expires, low sensor batteries causing erratic readings, loose door or window sensors that trigger when the wind rattles the frame, and insects walking across camera motion sensors. Most false alarms have simple causes and simple fixes. See our common security mistakes guide.
What Happens with Self-Monitored Systems (Ring, Yale, SimpliSafe without monitoring)
Your phone receives an alert. The siren sounds. You check the live camera feed, confirm it is a false alarm, and disarm via the app. No emergency services are contacted. Your neighbours may hear the siren and knock to check. The main consequence is noise disruption and mild embarrassment. To stop the siren quickly: disarm via the app or enter your PIN at the keypad.
What Happens with Professionally Monitored Systems
When your alarm triggers, the monitoring centre attempts to contact you by phone. If you confirm it is a false alarm, no further action is taken. If you cannot be reached, the monitoring centre contacts your nominated keyholders. Police are only dispatched if the monitoring centre cannot verify the alarm is false — and even then, repeated false alarms can result in a caution or the property being listed as low-priority for police response. See our monitoring guide.
How to Reduce False Alarms
Use pet-immune PIR detectors (check the kg threshold matches your pet). Set entry and exit delays generously — 45–60 seconds is better than 20 seconds for busy households. Check sensor battery levels every 3 months. Secure loose sensors properly. Configure motion sensitivity in the app to medium rather than maximum. See also: alarm systems hub, PIR motion detector guide.
