Individual door alarms are simple to install yourself should you wish not to spend thousands of dollars on a full-service home security system. Once you understand the principles behind alarms and how they're triggered, you see that any dynamic device (doors, windows, cabinets, what have you) may be fitted with an alarm. It just so happens that doors tend to protect the majority of things--our families included--that we most seek to protect.

For about 10 dollars, you can buy a stand-alone door alarm that's simple to put together. The average device consists of nothing more than a lithium battery, a spring-driven latch, a small magnet, and a buzzer. The latch is lined up opposite the magnet on the door and entryway respectively so that a circuit is formed. Whenever that door is opened, the disruption triggers a relay (part of your buzzer), which in turn sounds the alarm or summons the cops.

Alternatives to the Door Alarm

Rather than cobble together your own ad hoc door alarm system, it may be easier to buy a package of 10 or 12 separate alarms to place all along your home's perimeter. That way, if there are doors that don't need securing, you can skip over them and devote attention to those that do. Internal doors, for instance, are less likely to need alarms than those that connect your home or office with the outside world, since those are the ones burglars are likely to breach when forcing their way inside.

You may, on the other hand, determine that windows offer thieves the greatest temptation. Luckily, you can just as simply install basic home alarms systems in your window panes and panels. Once you've secured the premises with entry alarms, you can begin browsing motion detectors to find the models that offer you top-of-the-line protection.