3 Common Types of Window Alarm Sensors
Secure your windows to keep intruders out
Protecting your property isn’t just about locking and arming the front door. You can also provide a layer of security and control through window alarm sensors. These sensors can work within a smart home system or on their own as a lower-budget alternative to the cost of a home security system.
Generally, there are three types of window alarm sensors: contact, glass break, and motion. Knowing which one is right for your home isn’t always obvious. Explore each option below to figure out what will provide the most peace of mind.
1. Contact Sensors
Chances are you’ve come into contact with a contact sensor (pun intended). They’re the country’s most common type of window alarm sensor. These sensors come with two parts: a magnet that affixes to a window frame and the trigger, which is placed on the window’s sash so that the two connect when the window is closed.
If the window is opened while armed, the trigger sensor breaks contact with the magnet, which sets off an alarm. Contact sensors are easy to install and can also be hardwired through walls by a professional. Many of today’s smart home systems come with small, battery-powered contact sensors that most DIYers can set up themselves.
Due to the nature of their design, contact sensors won’t pick up on glass breaking if someone tries to enter through a window. Their price point also varies, from affordable to expensive, depending on the brand and product you choose and whether it’s part of a larger home security system or not.
| Pros | Cons |
|---|---|
| Easy to install, modern design | Won’t be triggered by glass break |
| Connects to smart home technology | Window locks may provide similar security |
2. Glass Break Sensors
In some homes, an intruder is more likely to smash the glass of a window than try to slide it open. These are the instances when glass break sensors will provide better security. They’re great for securing basement windows, garage windows, and anywhere else that residents are less likely to be around. They’re also a great option for any windows that don’t open at all.
Glass break sensors are designed to attach to the glass of a window so that whenever the glass surface breaks, or even vibrates, an alarm is triggered. There are also glass break sensors that are attuned specifically to sound, which trigger the alarm at a certain decibel level.
These sensors are small in size, but they can be seen from the outside of a window, so they may also be effective in warding off intruders from the start. Many security systems include glass break sensors, or you can purchase a kit separately.
| Pros | Cons |
|---|---|
| Visible deterrent to intruders | Won’t detect a window being opened |
| Connects to smart home technology | Ineffective on an unlocked window |
3. Motion Sensors
Motion sensors detect movement in a room or space and can be positioned to focus on a window or set of windows. That way, an alarm will sound if anyone approaches the window or attempts to open or break it. The best part is they still maintain their security if a window is left open or unlocked. This is a great option if you’re reluctant to make any changes to the windows themselves since no drilling is necessary, and nothing needs to be placed anywhere on the window.
Most types of home security systems come with motion sensors, whether it's a DIY smart home kit or installed by a local alarm systems pro. Their alarm can trigger lights, sound, a notification to your smartphone, or all three.
| Pros | Cons |
|---|---|
| Connects to smart home technology | Pets could trigger a false alarm |
| Secures open and unlocked windows | Weather can affect accuracy |
How to Choose the Best Window Alarm Sensor
There are a few key considerations to make when choosing your window alarm sensors. The type of windows you’re concerned about, your comfort level with the installation process, and how you’ll be monitoring the system, whether through a smartphone app or a larger home security system.
If you’re looking for a sensor to monitor a basement window or casement window, glass break sensors could be the right option. Or, for a ground-floor bedroom, a motion sensor might do the trick. You may end up requiring a few types of sensors for various windows of your home, which is still a relatively easy route, given the affordability of window alarm sensors.
Frequently Asked Questions
The best window alarm sensor depends on the type of window you’re concerned about since different types of sensors will work best in different scenarios. Many homes are equipped with contact sensors, which trigger an alarm when a window is opened, and each part of the sensor breaks contact with the other. But there are other options, too, like a glass break sensor or motion sensor, which both work well for windows that are in low-traffic areas.
Contact sensors come in two parts. A magnet is affixed to your window frame, and the trigger is attached to the window itself. Modern designs can be extremely minimal and compact in design so that they are nearly unnoticeable to residents and visitors alike. Glass break sensors are usually affixed to the window’s glass and are highly visible, which can create a deterrent for would-be intruders.