Your home is equipped with a security alarm to sound when an intruder gets in. Don't you want your house's biggest door to have one, too? Adding an alarm to your garage door is a several-step project, but well worth the trouble.
You will need an electric drill, a screwdriver, a pencil, a stud finder, and some drywall anchors.
First you have to clean off a section of wall where you want to attach the door sensor main unit system. Then locate a stud that is close to the highest point of the garage door frame- use the stud finder. (If you can't find a stud, you can use the drywall anchors.)
Hole up the main unit sensor up to the door, level it, and mark off where the top is. Then screw it in. (you'll have to drill the holes first, preferable into the stud)
Next, you have to decide where to put the magnetic switch- door jamb and door locations, making contact such that when the door is shut they are touching and when it's open they come apart.
Attach the magnetic switches, and attach the wires to the door sensor already installed. If you need help with these processes, you might want to call in a garage door services person.
Now your garage door alarm is ready to use. Padlocking is all well and good, but expensive items in the garage, or using the garage as another part of your home calls for a bit tighter security.