Choosing A Hinge
There are a few factors that should be considered when choosing which type of hinge should be used, including the weight of the door, the frequency of use and the environment. Obviously, the correct choice of hinge depends on the application.
Interior doors usually have two hinges, while heavier exterior doors usually have three.
Concealed hinges are used when the design mandates that the hinge not be visible. A knuckle hinge is the exact opposite of a concealed hinge, in that it is intended to be seen and admired.
High-use doors, such as employee entrances and main entrances, might require heavy weight, ball bearing hinges in a finish that can endure the weather and elements. Bearings offer the highest levels of durability and ease of operation.
Medium-use doors, such as trash removal or receiving doors, might require a medium weight, standard 5-knuckle hinge in a durable finish.
Light-duty doors, such as emergency exit doors, may require three or even four hinges.
To help ensure the door provides trouble free operation, the height, width and weight of the door should be considered when choosing the type of hinge and the number of hinges.