Butt Hinges

The common rule is one hinge for every 30 inches of door height or part of it: two on a door up to 5 ft, three over 5 ft up to 7 ft 6 in, and four up to 10 ft. Wide and heavy doors may need more. The door and hinge makers' guidance for your opening decides.

On a door that swings out, with its hinge pins on the outside. A non-removable pin (NRP) is held by a set screw or similar part that cannot be reached while the door is closed, which deters removing the pin to lift the door off from the outside. It is a deterrent, not a substitute for the opening's security hardware.

Only hinges that meet the door's listing. Hinge makers rule out brass on fire doors because of its low melting point, so fire doors hang on steel or stainless steel hinges. NFPA 80 covers fire door assemblies. The opening's listing, the door's size and rating, the code that applies and the hinge maker's tables decide the hinge material, size, gauge and number, and a standard weight hinge is limited to smaller rated doors than a heavy weight one. Check the product page before you order.

It carries wires through the hinge from the frame into the door, to power an electrified lock or exit device. The wire count has to match what the hardware needs. See exit control locks and electric strikes, which mount in the frame and need no hinge wiring. For doors hung on pivots instead, see pivot hinges.