Broken garage door spring? How to spot it and what to leave alone

How can I tell the spring has snapped?

Run through this quick check, from the house side of the garage if you can:

1. Did you hear a bang? People describe it as a gunshot or a heavy shelf falling, usually with nobody touching the door. Amarr notes a broken torsion spring can bang loudly while the broken pieces stay on the bar (Amarr).
2. Look at the coil. A sound spring is one tight, continuous coil. A broken one has a clear open space, as though a slice was cut out of it.
3. Watch what the opener does. It strains, lifts the door a few inches and stops, or reverses, or runs while the door hardly moves.
4. Look at the door itself. It may sit crooked, higher on one side, with a cable hanging slack at a bottom corner.
5. Remember the last close. A door that slammed down instead of settling softly is another sign.

You only need one of these. The split in the coil, on its own, settles it.

Which kind of spring does my door use?

Both are dangerous when they let go. An extension spring without a safety cable through its middle can whip across the garage, and Amarr warns that parts can fly. If one is hanging loose, don't reach in to tidy it up.

Why is running the opener a bad idea now?

The opener isn't a lifting machine. It guides a door that the springs have already balanced to feel almost weightless. Take a spring away and the opener is hauling the door's full weight, which is how gears strip, the top section bends where the opener arm attaches, and cables snap.

Lifting by hand carries the same risk from the other direction. Chamberlain warns that a door with weak or broken springs may fall rapidly and without warning (Chamberlain). That's enough weight to crush a hand, a foot or the hood of a car.

Leave the hardware alone, too. Garaga, a Canadian door maker, is blunt that torsion springs can be very dangerous (Garaga). Cables, drums and bottom brackets are all under the same load.

If the power is out after a storm and your car is inside, a broken spring rules out the manual release. Read garage door manual release for the checks to do before pulling that cord on any door.

One spring is gone but the door still runs. Can I keep using it?

No. A two-spring door shares its weight between both. When one breaks, the survivor is carrying a load it was never sized for, the door is out of balance and the opener is fighting it. That spring was installed the same day as the broken one and has done every cycle alongside it, so it's worn just as much and now overloaded on top. When it goes, nothing holds the door.

A door with one broken spring is a door with a broken spring. Stop using it and book the repair.

Why do springs fail in a salty, damp garage?

Every spring wears out eventually, because each open and close flexes the steel until it fatigues and cracks. What a coastal garage adds is corrosion, and corrosion speeds that wear up.

The door industry's technical sheet on spring life says rust reduces the effective area of the spring wire and its strength, and that corrosion pits can let fatigue cracks grow faster (DASMA TDS-190). The same sheet advises that doors near a saline coast, or in places with frequent precipitation, be kept closed where possible.

In Halifax that covers most garages: salt air near the harbour and the shore, road salt carried in on cars, and fog and wet spells that keep the inside of an unheated garage damp. A spring with rust along the coils, working a door that's stiff after a freeze-thaw night, is a likely candidate to snap.

How long springs normally last, and how to work out where yours are, is in how long do garage door springs last.

What happens on a spring repair visit?

A proper repair covers the whole counterbalance, not just the broken coil:

• Sizing the new spring to the door's weight, height and drum, so a heavier insulated door gets a stronger spring.
• Looking at both springs on a two-spring door, since they've worked the same cycles.
• Inspecting cables, drums and bottom brackets for damage from the shock of the break, and for salt corrosion.
• Balancing the door so it stays put when lifted halfway by hand.
• Testing the opener's safety reverse once the door is balanced again.

Garage doors are a 24/7 service. Until we arrive, leave the door as it is and keep everyone clear of it, then book garage door spring repair.

If the springs look intact and the door is stuck on an icy morning, the cause lies elsewhere; see garage door won't open in cold weather.