Garage Door Hinges, #1 to #10

What the number on a hinge means

Every hinge on a sectional door has a number pressed into the leaf: #1, #2, #3 and so on. The number tells you which joint it belongs on, counting up from the bottom. #1 hinges sit on the joint between the bottom section and the second section; #2 on the next joint up; #3 above that. On a four-section door the top section carries an adjustable top bracket instead of a hinge. Taller commercial doors run up to #5, #6 or higher, and the heavy 11-gauge range goes to #10.

The reason the number matters is the roller. The end hinges on each joint carry a roller stem through a tube on the hinge, and the tube sits a little farther from the door face on each higher number. That offset is what lets a flat door follow a curved track: as the door goes around the radius, each section leans back slightly more than the one below it, and the stepped rollers keep every wheel centred in the track. Swap a #1 and a #3 and the rollers bind at the curve, the door jerks, and the hinge leaf eventually tears out of the panel.

End hinges and centre hinges

Each joint has two end hinges (one each side, with the roller tube) and one or more centre hinges in the middle of the door with no tube. Centre hinges are all #1 regardless of joint because they do not carry a roller; they just hold the sections together. Wide doors have two or three centre hinges per joint. A 16' door with three centre hinges on three joints is nine centre hinges plus six end hinges plus two top brackets: seventeen pieces of hardware doing the bending.

14 gauge or 11 gauge

The gauge is the thickness of the steel: 14 gauge is about .075", 11 gauge about .120". On a residential door in Surrey or Langley the standard 14-gauge hinge is right. On a commercial door, a tall strata parkade door, or a heavy insulated or full-view aluminium door, the thicker hinge is the difference between hardware that lasts and hardware that cracks at the knuckle. Mixing the two on one door is a problem because the hole patterns and roller tubes differ.

How hinges fail

• Cracked knuckle. The rolled part of the hinge splits along the pin. Common on #1 end hinges, which carry the most sideways load at the curve. Shows as a click or clunk at the same point in every cycle.
• Elongated bolt holes. The hinge is fine but the panel skin around it has stretched or torn. On thin-skin steel doors this is the usual failure. The repair is a wide-body hinge, a backing plate or, on an old door, a strut behind the hinge line.
• Seized pin. Rust in the knuckle so the hinge does not pivot and the panel joint cracks open at the curve instead. Classic in damp garages; a drop of oil on each pin twice a year prevents it (see the lubrication guide).
• Wrong number fitted. A previous repair with whatever hinge was on hand. The tell is a roller that rides hard against the outer wall of the track on one section only.

Which hinges are safe to replace yourself

Centre hinges and end hinges on joints #2 and up are ordinary hardware. Close the door, unplug the opener, clamp the track above a roller so the door cannot move, remove one hinge at a time, and bolt the new one in the same holes with the same number. The bottom bracket is a different matter: it carries the cable, and the cable carries the spring tension. A bottom bracket, or the #1 end hinge directly above it on some doors, must not be loosened with the spring wound. That is the line: anything attached to the cable is our job; everything above it you can do with a socket set if you want to.

Replacing hinges on wood doors

Wood doors in older Vancouver and Richmond houses are a different animal. The hinge screws pull out of soft, wet wood, and the fix is longer screws into sound timber, or through-bolts with a backing plate across the joint like the slotted plate in the photo below. If the stiles are rotten the hinge will not hold whatever you bolt it to, which is when panel replacement or a new door comes into the conversation.