By Kent · Lock Depot Staff Writer

A door that has been rehung three times does not have a hinge problem. It has a load problem. The screws pull, the door drops, the top corner drags, somebody blames the closer and replaces it, and six months later the same work order comes back with a new date.

School entrances do this. Hospital corridors, restaurant kitchens, retail back-of-house doors, all of them, because they get hit hundreds of times a day by people with their hands full. At some point the answer is not another set of butt hinges. It is a continuous hinge, and we stock the Ives 700 and 702 pin and barrel continuous hinges in US32D satin stainless steel.

Why the frame edge gives up first

Three butt hinges carry the entire weight of that door on three short strips of frame and a handful of screws. Every swing loads those same points. The top hinge takes the worst of it because the door hangs off it, and that is why the top screws back out first and why the door leans toward the strike.

A continuous hinge runs the full height of the door and spreads that weight down the whole edge. There is no point for the load to concentrate on, so there is nothing to pull out.

Sometimes these are called geared hinges and sometimes pin and barrel, depending on how the leaves are joined. The 700-US32D-83 and its siblings are the pin and barrel type in stainless steel, right for a wet kitchen doorway or a wiped-down corridor.

Choosing a continuous hinge for a high traffic commercial door

The step up in price is real money, and the install is a different job from swapping three hinges. Be honest about whether the opening earns it.

It earns it when:

• The door is high cycle: a main entrance, a busy corridor, a kitchen door on the line.
• The door is heavy. Thick metal, glazing, a fire-rated core, applied hardware.
• It has a history of sag and you have already fixed it once.
• The frame edge is chewed up, so fresh screws have nothing clean to bite.
• Failure is disruptive: an ER corridor, a school entrance at arrival, a door on an egress path.

It does not earn it on a quiet office door that is behaving. Cycles and weight are the reason, not that it is the better part.

The security dividend

A continuous hinge also takes the exposed knuckles and individual pins off the edge of an out-swinging door. Real benefit on an exterior opening, but a bonus, not the reason you are buying.

The honest fork: sometimes a better butt hinge is the fix

Go look at the frame edge. If the mortises are intact, the metal is sound, and the hinges are just worn or squealing, you probably do not need a continuous hinge. A plain-bearing hinge on a heavy or high-cycle door is a slow-motion failure, and a common cause of the sag people call us about. Swapping to a heavy-duty ball-bearing hinge can fix that opening for a fraction of the cost. The long version: the ball-bearing hinge fix for a sagging commercial door.

Now the other branch. If the frame edge is already torn, if somebody has drilled and plugged it once, if the mortises have been welded or filled, fresh butt hinges are going into damaged material. Go continuous.

One more check while you are standing there. If the door swings back hard into a wall or a bollard, the hinge side absorbs that impact every time, and no hinge fixes an over-swing. An overhead stop catches the door before it over-swings and takes that shock off the hinge side.

What we stock

Both forks, from Ives:

Part	What it is	Where it belongs
700-US32D-85	Pin and barrel continuous hinge, satin stainless steel	Heavy or high-cycle door, damaged frame edge
700-US32D-120	Pin and barrel continuous hinge, satin stainless steel	Same, taller opening
702-US32D-83	Pin and barrel continuous hinge, satin stainless steel	Same family, different configuration
5BB1-3-5x3-5-600	Five-knuckle ball bearing full mortise, primed for paint steel	Heavy or high-cycle door, sound frame
5BB1-3-5x3-5-633	Five-knuckle ball bearing full mortise, satin brass plated	Same, where the opening is brass
3PB1-3-5x3-5-600	Three-knuckle plain bearing full mortise, primed for paint steel	Light, low-cycle interior door
3PB1-3-5x3-5-633	Three-knuckle plain bearing full mortise, satin brass plated	Same, brass opening

The difference between the two butt hinges is what sits between the knuckles. The 3PB1 is plain bearing: metal turning on metal, fine for a light door used a few times an hour. The 5BB1 carries the door on bearings, which is what belongs under weight and cycles. If someone put 3PB1 hinges on that door, you have found your culprit.

Getting the length right

These come in several lengths, and the number at the end of the part number is what changes between them. The hinge has to suit the door height. Measure the actual door, top to bottom, and call us with that measurement. Do not read it off the drawing. The door in the frame is often not the nominal size on the plan, especially if it has been cut down for carpet or a new threshold.

The retrofit reality check

Going from butt hinges to a continuous hinge is not a swap. Both edges get prepped for a full-height hinge, and if the frame edge is already damaged, that gets addressed first. Hanging a continuous hinge on torn material wastes the part.

Expect the door to come off and go back on with different clearances. That changes how the closer arm sits and how the latch meets the strike, so plan on adjusting both. Schedule it as a door job with the opening out of service, not a Tuesday afternoon item on a maintenance list.

Confirm this before you order

• Door height, measured on the door that is hanging there now.
• Door weight and material, and whether it has glazing or applied hardware.
• Frame material and the honest condition of the frame edge.
• Whether the opening is fire rated. That narrows what is legal on it.
• Whether there is a closer, and whether it is set too aggressively.
• The finish it has to match.

Common questions

Will a continuous hinge stop my door from sagging?

Yes, if the sag comes from load concentrating at the hinge points, which is the usual cause. The hinge carries the door along its whole edge instead of at three spots. It will not fix a bent frame, a door that was never square, or a floor that has moved.

Can I install one without taking the door off?

No. The door comes off. Both edges get prepped, frame damage gets repaired first, and the door goes back with clearances that will likely need the closer and strike adjusted.

How do I know which length to order?

Measure the door height and call us with the number. Several lengths are stocked and we will confirm the right one. Guessing from the door schedule is how the wrong part ends up on the truck.

Is a ball-bearing butt hinge good enough instead?

Often, yes. If the frame edge is sound and the old hinges are worn or plain bearing on a door that needed better, a set of 5BB1 ball-bearing hinges is the cheaper and faster fix. If the frame has already been repaired once, go continuous.

Does a continuous hinge help security?

It removes the row of exposed knuckles and individual pins along the edge of an out-swinging door. Useful on an exterior opening, but buy it for the load, not the lock line.

What finish should I order?

Match what is already on the opening. The continuous hinges we stock are US32D satin stainless steel. The butt hinges come primed for paint or satin brass plated. Tell us what the rest of the hardware is.