Garage Door Springs Explained: Types, Lifespan and What to Do When One Breaks

Ask most people what lifts their garage door and they will point at the motor. The motor is doing a fraction of the work. A sectional door can weigh as much as a couple of adults, and the reason a small electric opener on the ceiling can raise it, or a person can heave it up by hand when the power goes off, is that a spring is carrying nearly all of that weight the whole time. When the spring is right, the door feels almost weightless. When it is tired, everything downstream of it starts to suffer, and when it breaks, the door becomes a very heavy object with nothing holding it up.

What the springs do

A garage door spring is a counterbalance. It is wound or stretched to store roughly the same amount of energy as the door's weight, so that as the door comes down the spring loads up, and as it goes up the spring pays that energy back. The opener's job is to overcome friction and control speed, not to do the lifting. That is why a door with a healthy spring can be stopped halfway by hand and will sit there, and why a door with a weak one will drift down or need the motor to strain against it.

Torsion versus extension springs

Two designs do the same job in different ways. A torsion spring is a tightly wound coil that sits on a steel shaft across the top of the doorway, usually on the inside wall above the opening. As the door closes, cables on each side unwind from drums at the ends of the shaft and twist the spring tighter; opening lets it unwind and pull the cables in. A roller door works on the same principle with the spring hidden inside the drum the curtain rolls around. Extension springs are long, thin springs that run parallel to the horizontal tracks on each side of the door and stretch as it closes, pulling back through a pulley arrangement as it opens. They are the older system and are still found on tilt doors and some sectional doors from decades past.

• Torsion springs are the standard on new sectional and roller doors. They lift the door more evenly, wear more slowly, and stay contained on their shaft when they break.
• Extension springs are cheaper and need less headroom, which is why older brick-and-tile homes with tilt doors often have them. They wear faster and must have a safety cable threaded through them, because a snapped extension spring can fly across the garage.
• Torsion springs come as a single spring or a pair, depending on door weight. Heavier and wider doors get two, so that one breaking still leaves the door partly held.

Working out which spring you have

Stand inside with the door closed and look above the opening. A steel bar across the top with a coiled spring on it means torsion. Springs running along the tracks on either side, above the door when it is open, mean extension. A roller door with no visible spring at all has its torsion spring inside the drum. If you need the spring's specification for a replacement, the wire thickness, the inside diameter, the length and the winding direction all matter and all have to match the door's weight, which is why replacement springs are sized to the door rather than picked from a shelf. A heavier spring is not an upgrade: it will throw the door out of balance and fight the opener in the other direction. Match the original, or have the door weighed and the spring sized to it.

How long garage door springs last

Springs are rated in cycles, one cycle being a full open and close, rather than in years. A standard residential spring is commonly built for around ten thousand cycles, and higher-cycle springs are available at extra cost for doors that work hard. For a household that uses the door four to six times a day, ten thousand cycles works out to somewhere between about seven and twelve years; a busy family with several drivers can get there in five. Conditions matter too. Around Perth, salt near the ocean rusts a spring's surface and gives cracks somewhere to start, a hot garage bakes the lubricant off the coils, and a door that was never balanced properly overloads the spring on every cycle.

Signs a spring is on its way out

A spring rarely goes from perfect to broken without warning. The door gets heavier to lift by hand and the opener starts to sound as if it is working harder, slowing near the top or stopping short. The door may open a few inches and stop, or come down faster than it used to and hit the floor with a thud. Visually, a torsion spring that is failing often shows a gap between the coils that was not there before, or a bend in the shaft, and both springs of a pair can look slightly different in their pitch. Rust pitting on the coils is a sign the wire is thinning. Any of these is a reason to book a check rather than wait, because the next stage is a bang.

What to do when a spring breaks

The break itself is usually unmistakeable: a loud crack from the garage, often at night, with nobody near the door. Afterwards a torsion spring shows an obvious gap of a few centimetres somewhere along its length, and the door will not lift more than a little way, or the opener will strain and stop. From this point the door is dead weight held only by the cables and the opener's trolley. Do not keep pressing the remote, because the motor is now trying to lift the whole door and will strip its gears or burn out. Do not try to lift the door by hand unless you have to, and never with anyone underneath it. Leave it closed if it is closed. If it is stuck open, the manual release guide explains how to lower it safely with two people, and our broken spring or cable checklist covers what to look at before we arrive.

On a door with two torsion springs, a good technician will nearly always recommend replacing both at once. They were fitted together, they have done the same number of cycles, and the second one is close behind the first; replacing it now saves a second call-out and keeps the door balanced with a matched pair. The lifting cables should be checked at the same time, because a snapping spring often kinks or frays them, and a cable that then lets go is its own problem, which the cable repair page explains.

What replacement costs depend on

Spring replacement is one of the most common repairs we do, and the price moves with a handful of things: whether the door has one spring or two, torsion or extension, a sectional or a roller door, the size and weight of the door and therefore the spring it needs, whether the cables and drums need replacing at the same time, and whether the job is at a normal hour or outside them. A standard spring on a single sectional door in a suburban garage sits at the simpler end; a wide double door with a pair of high-cycle springs, new cables and a re-balance is a bigger job. The spring replacement cost guide walks through each of those factors, and the spring repair page for Perth explains how a visit runs. There is no call-out fee and the price is agreed with you before we touch the door. Most spring replacements are done the day they are booked.

Why spring replacement is not a DIY job

This is the one garage door repair where the warnings are not a sales tactic. A torsion spring at full tension stores enough energy to lift a door weighing as much as two grown adults, and that energy is released through a cone held by two set-screws and two winding bars. Get the bar seating wrong, use a screwdriver instead of a bar, or let go at the wrong moment, and the spring unwinds in a fraction of a second through whatever is in the way: hands, forearms, faces. Extension springs are marginally safer to handle but are the ones that fly across a garage when released badly. Then there is the sizing: a spring that is close but not right will leave the door out of balance, and the opener will pay for that every day until it fails.

The right tools are a proper pair of winding bars that fit the cone, a way to lock the shaft, clamps to hold the door down, and a set of springs sized to the door's actual weight. The technique is a matter of doing it many times. That is what you are paying for when you call: a spring that matches, tensioned so the door balances, with the cables and drums checked and the opener's limits reset afterwards. We take spring calls at any time of day or night, because a door that will not open at six in the morning is not something you can leave until business hours.

For the safety side of any powered door, Product Safety Australia publishes recalls and warnings, and if a spring job goes wrong after you have paid for it, WA Consumer Protection sets out what a tradesperson owes you.