Honeywell Glassbreak vs Window Sensors

We recommend that every security system include door sensors for every functional door leading into and out of the protected premises. Once the doors are protected, there are many different ways to protect the rest of the house.

While most criminals do break-in through a door, windows can also be used as a point of entry. Therefore, it is important that you enhance your security with extra perimeter protection beyond just the doors.

To protect your windows, you can use glass break detectors and/or window sensors. Window sensors work just like door sensors. In most cases, they consist of a magnet and a contact with an internal reed switch. When the window is closed, the magnet is close to the reed switch which causes the circuit to be seen as closed. If the window opens, the magnet gets pulled away from the contact, the circuit opens, and, if armed, an alarm is triggered. Therefore, window sensors will only cause an alarm if the actual window is opened. To protect against someone shattering your window and climbing into your home without opening the actual window frame, you can use glass break detectors.

Glass break detectors use an audio sensor, along with a special processor to detect the frequencies of glass being struck (low frequency) followed by the frequency of glass actually breaking (high frequency). Typically, a glass break sensor is mounted on the opposite wall or ceiling from one or more windows and if any window within range is shattered while the system is armed, the glass break will trigger the alarm.

Shock sensors are another type of glass break detector. Mounted directly to the glass being protected, shock sensors detect vibration, and can sound an alarm when glass has been struck, even before the glass is broken. These are less sophisticated than glass break detectors, are also less expensive, and are more prone to false alarms.

For full protection, you would need a window sensor on every window where it's possible to climb in from outside, in conjunction with a glass break detector in each room with windows or glass doors. With both devices installed, it would be nearly impossible for a burglar to break in without setting off the alarm, when armed.