Determined thieves may lift the door off its tracks. Insert screws along the upper track of the door. Leave enough room for the door to slide, but not enough space to lift the door out. Drill a hole and insert a nail through the inside frame and part way through the metal doorframe. You can remove the nail, but a burglar cannot.
Casement windows provide good security.
Make sure the cranking mechanism works properly and that there is no excess play between window and frame. To add more security, remove the operator handle and store in a convenient place. Lights Lights should be kept on at exterior doors every evening from dusk to dawn to improve visibility of your house so that your neighbors and passing officers can keep an eye on it. Make your house and address visible to emergency vehicles should you have an emergency at your home. A photoelectric switch at the front of the house switches the lights on automatically at dusk.