In the coming days, Google's modular Nest Secure alarm system will gain a new ability. The microphone inside the Nest Guard keypad, which was previously used only for the Assistant functionality, will start pulling double-duty to detect for the sound of glass being broken on windows and doors. The idea is that even if your Nest Detect sensors aren't disturbed by a broken window, the Guard may still be able to alert you to a break in.

To turn on glass break detection, you'll have to go inside the Nest app to turn it on as it'll be set to off by default. Here are the steps to turn it on:

  1. Open the Nest app and tap on the Settings icon on the home screen.
  2. Tap SecuritySecurity levels.
  3. Choose Away and Guarding or Home and Guarding.
  4. Tap Glass break detection.
  5. Turn on Glass break detection then set the amount of time you want before the alarm goes off.

To turn on Glass break detection for both security levels, you just need to go back to step 2 and activate for the other mode in the same way. This feature is already enabled on some systems. Here's what it looks like.


Google recommends that the Nest Guard be placed within 15 feet of any windows or doors you want monitored, ideally with no obstructions in between (e.g. walls or heavy curtains). In addition, it recommends turning on glass break detection only during quiet times, like when the house is empty or when everyone's sleeping, to improve accuracy. The Nest Detect sensors cannot be used to detect for breaking glass as they don't come equipped with microphones.

Google assures Nest Secure owners of their privacy by claiming that any audio that's recorded by the Nest Guard's microphone is locally processed and not sent to any of the company's cloud servers for analysis. You will also be prompted to enable the microphone in a separate step if you were not previously using it for Assistant. Should you experience any difficulty getting glass break detection to work, Google has prepared a list of troubleshooting steps on its support site.

Developer: Nest Labs Inc.
Price: Free
  • Source:
  • Google Support (1),
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