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Door Sensors: How They Work and Why You Need Them for Home Security

Apr 13, 2023|

As homeowners, protecting your property and loved ones is always top of mind. The threat of burglary, break-in, and home invasion can leave you questioning your home’s security. Installing door sensors can help ease those fears and make you feel more secure in your home.

Door sensors secure entry points, including doors and windows. They alert you to attempts to enter your home through doors or windows and, paired with alarms, can scare off would-be invaders before they ever step foot on your property.

In this guide, we’ll discuss everything you need to know about sensor technology, including:

  • What door sensors and window sensors are
  • How sensors work
  • What features to look for
  • The advantages of window sensors and door alarm sensors
  • How long sensors last
  • How much sensors and installation cost
Woman looking at the door and window sensor installed in her home.

What are door sensors?

Door sensors attach to your home’s entry points, including your front door, back door, garage door, and windows. When installed, these sensors notify you when someone enters your home or tampers with your entry points.

When a security alarm is not engaged, the sensors notify you of a door opening or closing. When your security alarm is engaged, any intrusion will trigger an audible or silent alarm, depending on your preferences.

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How door sensors work

Three are three distinct types of door and window sensors: magnetic contact sensors or reed switch sensors, motion sensors, and glass break sensors. Each one functions a little differently.

Magnetic contact sensors

Magnetic contact sensors, sometimes called reed switch sensors, consist of two halves: one half is installed on the door or window, and the other half is installed on its frame. Sensors are carefully aligned to create a closed electric circuit. When the magnet is disengaged—such as when someone opens the door—it interrupts the magnetic sensor circuit and signals an entry notification, such as a beep or chime. When paired with a home security system, the broken circuit sets off your alarm system until you enter a safe code on the system panel.

Motion sensors

Motion sensors leverage infrared technology to detect signs of movement. They trigger your notification or alarm upon detecting door or window movement. Motion sensors can also trigger an alarm if they sense tampering with window frames or doors.

Glass break sensors

Glass break sensors detect the sound of breaking glass and trigger an alarm. Many glass break sensors can detect glass breakage from 20 to 25 feet, meaning you’ll only need one for every average-sized room.

Door sensor.

Common features of door sensors

Door sensors come with a wide variety of features that make them incredibly valuable in protecting your home.

  • Alarm systems. When you integrate sensors into your alarm system, you can activate and deactivate them through your alarm’s keypad.
  • Integration with home automation. By integrating your sensors with your smart devices (such as Google Assistant or Amazon Alexa), you can check the status of entryways at any time. You can also set up your smart devices to smart lights on when your door opens.
  • Wireless connectivity. Once connected to your Wi-Fi, your system can send your phone notifications whenever your door opens or closes.
  • Long battery life. Door sensors have an average battery life of one to five years, so you can install them and leave them to do their job.
  • Adjustable sensitivity. Something as simple as a wandering animal can trigger your door sensors and window sensors if they’re too sensitive. Most sensors let you adjust sensitivity levels to reduce false alarms and detect only serious threats.

Benefits of door sensors

Why should you add door sensors to your home’s security system? Let’s look at how this simple technology can enhance your personal security.

Enhanced security and protection

Home invasions and burglaries are top concerns for many homeowners. Door sensors offer an added layer of protection by providing an early warning whenever someone tries to access your home without permission.

Having sensors in place can also help discourage property damage. For example, motion sensors can alert you to activity on and around your property and trigger alarms or flashing lights to scare off trespassers.

Convenience and ease of use

Door sensors are incredibly easy to use. Once installed, you’ll receive notifications of all entry activity impacting your home, giving you peace of mind that the only people in your home are those you invited.

While DIY sensor installation kits exist, surface-mounted sensors can be tricky to properly line up. Professional installation ensures everything is installed correctly, securing your home from day one. Vivint offers professional installation for all door and window sensors.

Integration with other security systems

Door sensors and window sensors integrate seamlessly with other home security technology. Adding door sensors to systems with security cameras and motion detectors provides comprehensive security to protect every corner of your property.

When adding door and window sensors to smart home systems, you’ll want sensors that can connect to Wi-Fi networks. You can remotely monitor Wi-Fi-compatible sensors via smartphone apps and configure them to send phone notifications every time someone enters or exits your property.

Check out Vivint’s security sensor options to see how door and window sensors fit into your home’s security picture.

Personalization and customization

Your property has unique security needs, and door sensors are easily customizable to fit those needs. You can adjust sensitivity levels, choose what kind of alarm you want, and connect sensors with your smart home devices. You can also choose where to install sensors, focusing security on the areas in your home that feel most vulnerable.

Peace of mind

We’ve all had that terrifying moment when a sound wakes us up in the middle of the night — was that someone entering my home or the wind blowing the screen door? Door and window sensors can give you peace of mind throughout your day and night. When your entry sensors are engaged, you can rest assured knowing your home is safe and secure.

Man adjusting his door sensor.

Door sensor FAQ

This section will answer a few frequently asked questions about door alarms and sensors, including their operation and price points.

What is the average lifespan of door sensors?

Door and window sensors last an average of 10 years before needing replacement. Batteries for sensors require replacement every one to five years. Of course, the lifespan of door sensors also depends on various factors, including the type of sensor, product quality, and usage rate.

Do door sensors need Wi-Fi?

Basic sensors do not require Wi-Fi; most door sensors use a short-range RF signal to communicate with the alarm system panel.

You will need Wi-Fi to take advantage of advanced smart sensor features like remote monitoring. You can control Wi-Fi-enabled entry sensors using smart home devices and smartphone apps, giving you access to your home’s security information at all times, no matter where you are.

How much do door sensors cost?

The answer to this question largely depends on the features you want and the size of your home. Basic door alarm sensors without smart features like remote access cost between $20 to $50 for a multipack. For more complex systems that utilize smart door technology and wireless door sensors for multiple entryways, you’ll pay upwards of a few hundred dollars to put a sensor on each door.

Discover the leading home security system solutions from Vivint

Burglar alarm and sensor technology, including door and window alarm sensors, have come a long way in the past few years. These sensors have prevented countless home invasions and helped many people feel safer in their homes.

Call Vivint today at 855.822.1220 to learn more about our best door & window sensors or talk to a security expert about your specific needs.

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