How Does a Glass Break Detector Work?

Door and window sensors sound an alarm when someone opens a door or window to your home. But if a burglar were to break into your home by smashing a window—instead of forcing it open—the window sensor wouldn’t trigger.

Glass break detectors complement door and window sensors by monitoring sound or vibration. When they detect the frequency or shock waves associated with glass shattering, they sound an alarm. These devices are great additions to home security because they can remain armed all the time, unlike motion detectors, which must be turned off when you or your family are at home.

Here’s a closer look at the technology that makes these window break alarms work.

Protect your property
Sign up for our weekly newsletter to get the latest deals, home security tips, and in-depth reviews.

By signing up, you agree to our Terms and Conditions and Privacy Policy.

The science behind glass break sensors

Glass break detectors are ideal to use in rooms with large windows and sliding doors. The detector is a small device you attach on or near your windows. Like a motion sensor, the range is limited, so you’ll likely want multiple glass break detectors for your home.

There are two main types of glass break alarms. The first type features shock sensors, which monitor for the vibrations of breaking glass. These are generally mounted directly on the windows they’re monitoring. It’s worth noting that these types of detectors can sometimes set off false alarms, as a door slamming could mimic the same vibrations of glass breaking.

If you’re worried about false alarms, you can opt for a glass break detector that relies on acoustic sensors instead. A small microphone listens for the specific frequencies of breaking glass. If a burglar were to break through a window, the detector would pick up on the high-pitched shattering sound to trip the alarm.

Adjusting device sensitivity

When considering glass break detectors, many people worry about triggering false alarms if they accidentally break a glass plate or are watching an action movie. Potential false alarms are why you should test and adjust sensitivity levels when you first install your glass break detectors.

The testing process will differ depending on the detector you purchase, but most have a “test” button. When testing, you’ll clap your hands loudly near your windows. You can also play a video of glass sounds for greater accuracy.

Even after testing, there’s always the chance of a false alarm, so you may want to avoid placing glass break detectors in the kitchen or near your television, where other shattering noises are likely to be loudest.

Wondering what home security companies offer glass break detectors? Check out the packages offered by our top home security company picks to find out.


Compare the best home security systems

Brand
Best for
Lowest monitoring price
Starter equipment price
Contract required
Installation
Smart home compatibilityIcon Tooltip  Dark
Learn more
Read review
Best overall$599.00
Icon Yes  LightNo *
ProAmazon, Google,
Z-Wave
Budget pick$245.00
Icon Yes  LightNo
DIYAmazon, Google
Most experienced $0.00
Icon No  LightYes
ProAmazon, Google,
Z-Wave
Best customer experienceQuote required
Icon Yes  LightNo *
DIYAmazon,
Google
High-end DIY pick$129.00
Icon Yes  LightNo
DIYAmazon, Google,
Z-Wave

Info current as of post date. Offers and availability may vary by location and are subject to change.
Full ADT disclaimer

Celeste Tholen
Written by
Celeste Tholen
Celeste has dedicated her decade-long career to reporting and reviews that help people make well-informed decisions. She oversees editorial strategy and production for SafeWise, with a goal to help everyone find the information they need to make their homes and lives safer. Prior to SafeWise, she worked as an editor and reporter for KSL and Deseret News. She holds a Bachelor's degree in Journalism. In her free time, she volunteers at the local botanical garden and writers for the community newspaper.

Recent Articles

watching camera feed on tablet
Best Wireless Security Systems
Wireless home security systems are more popular than ever. They’re easy to install and hard...
security system being installed on wall
Best DIY Home Security Systems of 2022
DIY install home security systems are cost-efficient, effective, and easy to install. See which DIY...
Neighbourhood homes in the United Kingdom
The Best Home Alarm Systems in the UK
Find the right alarm system to protect your UK home. SafeWise recommends security systems for...
safewise's best home security systems
10 Best Home Security Systems of 2022
After hundreds of hours of tests and research, plus a combined 50+ years of experience,...