A security hinge is a protective feature that prevents potential crime, such as theft or vandalism, by making it difficult to remove a door by tampering with the hinges. They may be used on exterior doors for security, as well as in secured facilities where containment within a building is necessary. In addition to providing protection from threats like vandalism, most also have a fire rating which indicates how long they should remain intact in high heat conditions. Hardware and home supply stores sell security hinges and accessories that can be used to convert existing hinges to make them safer.
One concern with hinges is that if hinge pins face out, it is possible to remove them and then take the door off. The security hinge can use several different features to make it either difficult to remove the hinge pins, or hard to take the door off by removing the hinge pins. Flanges and set screws can hold the pins in place, for instance, or stud screws can hold the two sides of the security hinge together even after the hinge pin is removed. Vandals may attempt to break in by tampering with the hinges, but they should resist long enough to deter them or allow someone to notice and call for assistance.
Installing security hinges can require removing existing hinges to place new ones, or retrofitting hinges to install a feature like a stud. One important consideration is that securing the door may also make it more difficult to work on in the future. The same features that prevent removal of the door when it is not desired can also make it hard when people need to work on it. For example, flanges on the pin will make it necessary to take the security hinge off entirely to remove a door. This could be a concern in the future if a door needs to be repainted or repaired.
When selecting security hinges, it is important to think about weight and fire resistance ratings. The security hinge should be heavy enough to handle the weight of the door as well as anticipated uses. Secured doors should ideally be heavy to make them difficult to break down and add fire resistance, and hinges may provide information on how much weight they can comfortably bear. Fire resistance ratings offer an estimate on how long hinges will hold up in a fire, and a fire department can provide specific advice on the best ratings for a given structure.