Every commercial building in Toronto has them, and almost nobody looks at them until one stops working. The horizontal bar across an exit door — a panic bar, or more properly an exit device — is the piece of hardware that lets a room full of people get out under pressure without anyone needing to know how a lock works. When it fails, it tends to fail in one of two directions: the door will not open when it should, or it will not stay shut when it should. Both are serious, and they have very different causes.

What the bar is actually doing

An exit device replaces the normal latch and handle with a mechanism that retracts the latch when anything presses on the bar. There is no thinking involved and no knob to turn, which is the entire point. Push, and the door opens.

Underneath that simple idea sit a few different arrangements, and knowing which one is on your door explains most of its problems.

Rim devices

The latch sits on the surface of the door and catches a strike mounted on the frame. These are the most common on single storefront and back-of-house doors, and the easiest to service. When they go wrong, it is usually the strike that has shifted or the latch that is no longer being fully retracted.

Mortise devices

The lock body is buried inside the edge of the door. Heavier, quieter, and generally found on main entrances where appearance matters. Repairs take longer because the door often has to come off to get at the mechanism.

Vertical rod devices

Rods run up and down inside or alongside the door to latch at the head and the sill. These are what you find on double doors with no centre post. They are also the most trouble-prone, because the rods go out of adjustment as the door settles and the top latch stops reaching its strike.

The failures that come up again and again

The door does not latch after it closes

Someone pushes the door shut and it swings back open an inch. On a vertical rod device this almost always means the rods need adjustment — the top latch is not travelling far enough to engage. On a rim device it is usually the strike, which has worked loose or been knocked by a cart. Either way, an exit door that does not latch is an unlocked building, and it stays that way until someone notices.

The bar has to be hit hard

A bar that needs a shove rather than a push has friction somewhere — a dragging latch, a bent rod, a door that has dropped and is binding on the frame. This matters more than it sounds. The whole premise of the device is that it works for a person who is panicking, in the dark, possibly being pushed from behind. A bar that an able-bodied adult has to lean on is already failing.

The bar rattles or sits crooked

Mounting screws back out over years of impact. Once the chassis has play in it, the alignment between the bar and the latch drifts and the whole thing wears faster. Catching this early is a tightening job. Leaving it turns it into a replacement.

The dogging has been left on, or has stopped working

Many devices can be dogged — held with the latch retracted so the door pushes open freely, which is how a shop keeps its back door easy during a delivery. That is fine while the building is occupied and staff know about it. It is a problem when someone dogs a door and forgets, and the building is left unsecured overnight. Fire-rated exit devices cannot be dogged at all; if one on a rated door appears to be held open, something is wrong and it needs commercial door repair attention rather than a workaround.

The door has been forced

After a break-in attempt, exit devices often look intact and are not. The latch may be bent, the strike pulled, the frame spread at the lock edge. The door closes, so it gets left — and then it fails on a day when it matters. Anything that has taken a pry bar deserves a proper look, which is what burglary repair work is for.

What gets written up on an inspection

Exit hardware sits where fire safety, building code and accessibility all overlap, so it gets looked at. The items that come up most often are not exotic:

• Anything added to the door that needs a second action to get out. A padlock, a chain, a deadbolt thumb turn, a slide bolt added by a well-meaning employee. Exit means one motion, in the direction of travel.
• A door that does not fully close and latch on its own. On a fire-rated opening this is a straightforward failure.
• Obstruction on the exit side. Stock stacked against the door, a mat that catches under it, a pallet parked in the swing path.
• Signage and visibility where it is required.
• A device fighting its closer. If the closer cannot drive the latch home, the door is left unlatched, and the pairing needs sorting out rather than one half of it being replaced.

None of these need a specialist to spot. A walk-through with someone willing to actually push each bar will find most of them.

What to do between service visits

Exit devices respond well to being left alone and badly to being lubricated with the wrong thing. A few habits that help:

1. Push every exit bar in the building once a month and note anything that needs more than light pressure.
2. Watch each door close on its own from fully open and confirm the latch engages without help.
3. Check the exterior side for pry marks, especially on back doors facing a laneway.
4. Keep the exit path clear, and make it someone’s job rather than everyone’s.
5. Do not spray heavy grease into the mechanism. It collects grit and makes the problem worse in a year.

If a door fails any of this, it should be treated as urgent rather than scheduled. A jammed exit on a Friday afternoon is a reason to call for emergency door repairs, not a Monday ticket.

Frequently asked questions

Can I lock an exit door from the outside?

Usually yes — most devices accept an outside trim with a cylinder so staff can get back in, while the inside stays free-exit at all times. What is not acceptable is anything that restricts getting out from the inside.

Is a chain through the bars ever allowed?

No, not while the building is occupied. It is the single most common serious finding on an exit door, and it is the one with the worst consequences when it goes wrong.

Why does the top latch on our double doors keep missing?

Vertical rods need periodic adjustment as the door and frame move. If it has started missing repeatedly after being set, look at whether the door has dropped on its hinges or the frame has shifted, because the rods will keep going out until that is addressed.

The bar is noisy. Does that matter?

Noise on its own is not a fault, but a new rattle or a clunk that was not there before usually means something has loosened. Worth a look before it becomes a seized mechanism.