Garage door spring repair and replacement
A broken spring is the most common garage door failure there is, and it is the one repair a homeowner should never attempt. We replace torsion and extension springs across Hamilton, Stoney Creek, Grimsby, Burlington and Niagara, same-day in most cases, with the spring matched to the door's actual weight and to a cycle rating you choose.
How to tell it is the spring
You can usually diagnose this from the driveway, without touching anything.
A visible gap in the coil
Look at the spring on the bar above the door. A torsion spring is a tight, continuous coil. If there is a two- to three-inch gap in the middle of it, that spring is broken. This is the single clearest sign there is.
The door lifts about six inches and stops
The opener pulls, the door rises a few inches, the opener gives up and reverses. With no counterbalance, the motor is trying to lift the whole door on its own and its force limit stops it. That is protection working, not a broken opener.
A bang like a gunshot from the garage
A torsion spring letting go is loud enough to wake a house, and people usually describe it as a gunshot or something falling off a shelf. If the door will not lift the next morning, that noise was the spring.
The door is suddenly enormously heavy
A balanced double door can be lifted by hand with moderate effort. If it now feels immovable, the springs are not carrying it any more. Do not keep trying: the weight is real and it is coming down.
Do not attempt this repair. A torsion spring holds enough energy to lift the entire door, and it releases all of it at once if it is unwound wrong. DASMA's own data sheet on spring identification says in its opening paragraph that it "should not be used by homeowners or maintenance personnel to replace garage door springs" and that replacement "should only be performed by a trained door systems technician."
If a spring is broken, do not operate the door at all, by hand or with the opener, until it is replaced.
Torsion or extension: which one you have
Both types are still in service across this area, and they fail differently.
| Torsion | Extension | |
|---|---|---|
| Where it sits | On a steel shaft above the door opening | Along the horizontal tracks, one on each side |
| How it works | Twists to store energy, winds cables onto drums | Stretches to store energy, pulls through a pulley |
| Failure signature | Loud bang, visible gap in the coil | Spring hangs slack, door sits crooked |
| Safety containment | Contained by the shaft it is mounted on | Needs a containment cable through the middle |
| Typical on | Most doors installed in the last 25 years | Older and lighter single doors |
If you have extension springs and there is no cable running through the middle of them, that is worth raising when you call. A containment cable is what stops a failed extension spring from becoming a projectile.
Springs are sized to the door, not to the opening
Two doors the same width can need completely different springs, because insulation, glazing, gauge of steel and even a repaint change the weight the spring has to carry. DASMA lists "applying a spring to the wrong door" as a real failure mode and notes that a spring which does not match the door's counterbalance requirement can shorten the life of the door assembly and the opener, and can create a safety problem with manual operation.
Source: DASMA Technical Data Sheet #190, Factors Affecting Spring Cycle Life (PDF), Installation Factors. Checked 31 August 2026.The same sheet warns that adding weight to a door after the fact, including paint, can push it past the manufacturer's specification for the springs already fitted. It is worth mentioning if your door has been repainted since it was installed.
You get to choose how long the next set lasts
Springs are rated in cycles, where one cycle is one full open and close. The springs commonly supplied on the market are rated at about 10,000 cycles. Higher-cycle springs are a stock item, not a special order, and the price difference is small next to the cost of a second service call.
What we replace, and why it is usually both
On a two-spring door we replace both springs even when only one has broken. They were installed the same day, they have taken the same number of cycles, and the second one is typically weeks or months behind the first. Replacing one means paying the call-out twice.
A spring job also includes the parts that wear alongside it: the bearings the shaft turns in, and the lift cables, which fray from the same fatigue that kills a spring. If the cables are sound we say so and leave them.
What it costs
We will not print a price here, because the honest number depends on the door's weight, whether it is one spring or two, the cycle rating you choose, and whether the cables and bearings need doing at the same time. You get a written price before any work starts, and it does not move afterwards unless something is found that changes the job, which you approve first.
What happens on the call
- The door gets weighed, in effect. With the counterbalance released, the technician can measure what the door actually weighs rather than guessing from its size.
- The old springs come off and the new ones are wound to the manufacturer's turn count. DASMA is specific that the number of turns should always follow the door manufacturer's instructions: too much torque overloads the rest of the counterbalance, too little leaves the door drifting down out of the open position.
- Cables and bearings are checked while the system is apart, because that is the only time it is cheap to do.
- The door is balance-tested. Opener disconnected, door lifted to about waist height, released. A correctly balanced door stays roughly where it is put.
- The opener is reconnected and the safety reversal is tested before we leave.