What Is a Driveway Alarm Used For and How It Works

Driveway alarms are devices that detect motion and are used to beef up home security. Learn the difference between different alarms and how they work.

Driveway alarms are wireless electronic devices that serve the purpose of notifying you whenever there’s movement on your driveway. Some alarms are designed to detect people, animals, cars or all three. The biggest benefit of using such an alarm is safety. You’ll instantly be notified when an unexpected visitor pulls on your driveway or someone is trying to trespass on your property.

However, not all home owners will benefit from having a driveway alarm system installed. If you have a small 2 to 6 cars driveway, which you can easily view from the house, there is no need to constantly check all the incoming traffic. A driveway alarm will be more useful to people with long driveways or small driveways that are not visible from inside the house.

How a Driveway Alarm Works

Driveway alarms consist of 2 main components: one transmitter and one receiver. The transmitter usually runs on batteries and it’s placed somewhere concealed, on the side of the driveway, at the entrance. The receiver is kept in your home, plugged into an electrical outlet. Depending on what brand and model your purchase, the receiver may come as a wireless option, in which case you can care it with you. Whenever the transmitter senses a moving object, it will send a signal to the receiver, which in turn will notify you by either a sound, led lighting or both.

Types of Driveway Alarms

Driveway alarms fall into two main categories:

  1. Wireless or hard wired – one is no better than the other and this is only a matter of personal preference.
  2. Detection type – thee are alarms that detect people (and animals), vehicles, and both. Therefore, before buying an alarm for your driveway, you need to think about what do you need it for: to know when people trespass or to get notified whenever a deer is wondering around your property?

Types of Sensors

There are several types of sensors used in driveway alarms. Here’s what you need to know about each type:

  • Infrared Driveway Sensors. These sensors are wireless and use heat to detect movement (people, animals or vehicles) by sending a signal whenever a warm object passes through the beam. The biggest advantage of infrared sensors is that they’re easy to install and are not expensive.
  • Magnetic Probe Driveway Sensor. These sensors are either hard wired or wireless and are used to detect metal objects only. Therefore, you will not get any false alarms due to animals or birds. One of the benefits of having a magnetic probe on your driveway is that the probe will be hidden from view once the installation is done. You also need to be prepared to spend more money on this type of sensor (over $100).
  • Rubber Hose Driveway Sensor. These sensors are enclosed in a soft rubber hose and are used to detect mostly vehicles. When a car passes over the hose, the hose is pushed down over the sensor, which in turns sends a signal to the receiver. You’ll get a notification is people or animals step on the actual hose. These sensor are inexpensive but you’ll need to replace the hose every once in a while, due to wear and tear.
  • Photo Beam Sensors. Driveway alarms that use photo beam sensors have two or more sensors. The sensors are placed at opposite ends and you only get a notification of movement when the beams from ALL sensors are broken at the same time. False alarms are virtually impossible since animals and birds cannot break all the beams at once. This is the best alarm system you can buy if you main concert is to detect people


Today’s driveway alarms include the latest technology and come with various features that make it really easy to detect objects or people. Here are two very popular features you should take into consideration before buying an alarm:

  1. Security Zones. A good driveway alarm system will allow you the possibility of adding additional sensors for different security zones – usually at least 4. For example, you could get 4 sensors and use the same receiver for different areas of your house (driveway, backyards, side of the house, etc…). Depending on where the sensors are located, the receiver will notify you when there’s movement and which sensor detected the movement. Some alarms have a different alarm tone for each zone. Other models use visual indicators by using a variation of led colors.
  2. Supervised Wireless Transmitters. This feature allows you to know when the sensor’s batteries run low. Supervised transmitters will send out two signals to the receiver: one for motion detection and one for low power in batteries. Without this feature you won’t know when batteries stop working.