Home Security Sensors 101: Understanding the Different Types and How They Work

September 9, 2025 by Anas Mustafa

It is easy to picture home security in terms of alarm sirens and video cameras, but the lesser-known heroes behind the scenes are the sensors. It is these discrete pieces of equipment that are most likely to notice something fishy occurring, whether it is a window opening when there shouldn’t be anyone inside or someone walking down the hallway at 2 a.m. when everyone is asleep.

Without sensors, your alarm system is just a loudspeaker with good intentions. A security sensor functions as the eyes and ears of the system. It watches day and night for signs of a break-in or trouble, issuing an alarm signal before you even realize anything is amiss.

Sensors also provide customization and control that help homeowners feel secure. You can define the exact zones to monitor and at what time, like arming the doors and windows when you’re home having fun, or all the motion detectors when your house is vacant.

There are also sensors that monitor the changes in the surroundings, such as smoke, carbon dioxide, or even water, to offer an added layer of protection. Thus, sensors are what make smart home security modern, responsive, and customizable.

What are the main security sensor types, and how do they work?

No truly exhaustive security system is ever complete without sensors. However, there are many different security sensor types available, all with their own functions, and thus different strengths and weaknesses.

To obtain optimal security, you need security sensors that are tailored to your requirements. Below, we will discuss the main security sensor types and how each works:

1. Motion sensors

Motion detectors are a key part of any modern home security system, using technology like passive infrared (PIR) or microwave radar to detect movement. They look for heat or changes in motion and relay an alarm if something odd is found, like a person walking down a hallway or into a room. Most systems allow you to adjust sensitivity so that false alarms from pets or environmental factors are avoided.

Paired with a monitored system, these detectors will notify you, and the monitoring station, if there is someone in your house when there should not be. They are ideal for common spaces, points of entry, and rooms you want to secure when you are not home or when you are asleep.

2. Glass break sensors

Glass break sensors fill a significant gap by detecting the sound of shattering glass, a method frequently used by intruders to bypass conventional door or window sensors. Glass break sensors use internal microphones to listen for the specific sound patterns of impact and shattering glass, thus reducing false alarms.

These sensors can cover an entire room with multiple windows, making it a cost-effective solution for open spaces with plenty of glass, like sunrooms or living rooms. The system sends a signal to a monitoring centre when triggered, and it can immediately notify you or dispatch help depending on the severity of the situation.

3. Temperature sensors

A temperature sensor protects your home from environmental hazards, like frozen pipes, HVAC malfunctions, or mould-growing conditions. They continuously monitor for unusual temperature changes, such as when the air around plumbing becomes too cold or excessively hot in areas like attics or basements. When the readings exceed a reasonable threshold, the sensor will alert you before something disastrous occurs.

The sensors are especially useful in parts of the home that are less frequently utilized yet still vulnerable to costly issues, such as crawlspaces, utility rooms, and around large appliances.

4. Flood sensors

Flood sensors will recognize water leaks or water accumulation before they can damage your property. They are fitted around water heaters, sump pumps, washing machines, sinks, toilets or in basements. The sensors detect water on the floor and send an alert immediately.

This early warning allows you to respond quickly—shutting off a valve or calling for service—before the issue escalates and leads to flooding, appliance destruction, or mould. If connected to a monitored alarm system, the monitoring centre will contact you to let you know and if they can’t reach you they will contact your emergency contacts.

5. Door and window sensors

Door and window sensors use a magnetic contact setup to record when an entry point is opened. Both the magnet and the sensor are set when your door or window is closed. When they separate, the system records it as a possible intrusion and sends an alert. These sensors enable you to monitor forced and unauthorized entry or exit, whether an intruder is attempting to get inside or a child is trying to sneak out.

The installation of this type of security sensor is usually focused on ground-floor and easy-to-reach openings, and the system can be programmed to contact the monitoring station after it is triggered.

6. Smoke and heat detectors

Smoke and heat detectors are your home’s early warning system for fire. Smoke detectors use photoelectric or ionization technology to sense smoke particles in the air, and heat sensors to sense extremely high or rapid increases in temperature.

These sensors are generally installed in sets throughout a house to provide complete coverage. Heat sensors are especially useful in the laundry room, garage, or kitchen, where smoke may be present without there being a fire.

If connected to a professional monitoring service, these sensors can have emergency responders dispatched even when you are not home.

7. Carbon monoxide detectors

Carbon monoxide (CO) detectors protect you from one of the most lethal home dangers: a toxic gas that is odourless and colourless. CO can be the product of malfunctioning gas stoves, furnaces, fireplaces, or other fuel-burning appliances. These security sensors employ electrochemical functions to detect CO levels and trigger a loud alarm if the gas is at hazardous levels.

When linked to a monitored system, they also alert your monitoring centre who then dispatch emergency responders if required. It is important to install them near sleeping areas and gas appliances. Regular testing ensures they are operational when required.

Contact Canadian Security Professionals for High-Quality Security Sensors

All the security sensor types mentioned above are essential for your home security setup if you want to make it as effective as possible and ensure maximum safety for your home and its occupants. Canadian Security Professionals can help provide such devices at an affordable cost.

We offer comprehensive home security system packages that include many different security sensors, including wireless door sensors, motion sensors, glass break sensors, and more. Our security packages are highly customizable, so they can be easily tailored to fit the needs of your family and home.

We also offer several other solutions to extend the security of your home to an even higher degree, such as video monitoring services, home automation systems, and various smart systems.

With our products and services, your family, home, and belongings will be safeguarded to the max. Whether you need to go out for a few hours or a few weeks, you can be certain that no suspicious activity will happen on your property without you knowing about it the moment it occurs.

For more information about our security sensor options or to learn more about other home security measures we have to offer, call Canadian Security Professionals at 1-877-494-9911 or contact us here.