Door Alarms

Door alarms are part of almost all security systems. Combined with window alarms, they protect the perimeter of your home from intrusion. Whether your system is armed or disarmed, door alarms let you know every time an exterior door opens.

Door alarms are basic to virtually every type and configuration of residential alarm system. They are designed to activate the alarm if someone opens an exterior door while the system is armed or activated. Most systems are equipped with a siren or other alarm that is heard inside and outside the house.

Like most sensors in your alarm system, sensors in door alarms are almost invisible. Some door alarms are hard wired to a system, while others are individually connected wirelessly to a single alarm. This flexibility is helpful if you are considering a simple security system for an apartment, for example.

Most door alarms are installed by placing a small magnet or piece of metal in the edge of the door and in the doorframe. When the homeowner activates the perimeter sensors, the sensors create a magnetic field. If someone opens the door and disturbs the magnetic field, the sensors set off the alarm.

Most security systems are designed to allow the homeowner to protect the perimeter of the home while allowing movement inside. Even systems with several types of interior motion or sound sensors offer the option of activating only the perimeter sensors. Knowing that the residents and their neighbors will be notified by door alarms offers a greater feeling of safety to many homeowners.

Door alarms generally make some type of sound if someone opens a door when your perimeter sensors are deactivated/disarmed. Most systems make an electronic beeping sound. Notification when someone opens a door serves several purposes:

  • You know someone has just entered the house and you can call to that person to identify him or her.
  • If you have young children, you know if a child opens an exterior door and possibly leaves the house.
  • If you have pets, you know you need to find out where the pet is when a door is opened.
  • If someone in the family has been outdoors for some reason, you know when they return.
  • If someone leaves a door open, you know it.
  • If someone opens a door without authorization, you can use the control panel to find out which door is open, notify the police (with the panic button) and safely leave the house by another door until police arrive.

When planning your alarm system, you should include door alarms on every exterior door in the house, including a door that opens from the garage or that opens above a basement. There are many reasons to leave a garage open, allowing access to the house. Even a door that seems inaccessible, such as a door from a porch or deck with no external access, can be vulnerable.

Many doors today include large glass panels – French doors, etched or stained glass panels – that make your home vulnerable to intrusion. These doors clearly need door alarms. Other types of doors can be opened by professionals, as well. Even steel security doors are vulnerable with the right combination of knowledge and equipment.

Even if a thief should gain access to your home and possessions through a window, he will activate the alarm when he opens a door to leave or remove your property. This is why door alarms are basic equipment in every residential security alarm system. When you secure the doors, you are well along the way to protecting the house and its contents.