It usually happens at night, and it does not sound like a garage door. It sounds like someone fired a rifle inside the house. People come down the stairs expecting to find a window gone and instead find the garage exactly as they left it, except the door will not budge and there is a coiled steel spring above it that is now in two pieces.

Then they look up and see the other spring, sitting there intact, looking entirely fine. And when the technician says both are getting replaced, a reasonable person hears the oldest upsell in the trade.

It is a fair suspicion. Here is the actual reason, and the cases where we don't do it.

Springs are not rated in years. They are rated in cycles.

A torsion spring is the part that does the real work in a garage door. The opener does not lift the door — a half-horsepower motor cannot lift 150 to 400 pounds of steel, and was never designed to. The spring lifts the door. The opener just decides when.

The spring stores energy by twisting. Wind it up and it holds enough torque to raise a double door with one hand; that is the whole point, and it is also why it is the one part on the door you should never take a wrench to.

What matters here is how spring life is measured. Not in years, and not in miles. In cycles — one cycle being one trip up and one trip down. A standard builder-grade spring is rated at 10,000 cycles. Better ones come in 15,000, 25,000 and 50,000.

That number is not a warranty. It is a fatigue estimate. Every time the spring winds and unwinds, the steel flexes, and each flex spends a small, permanent, unrecoverable fraction of the spring's life. Nothing about it is reversible. A spring does not wear out the way a tire does, gradually and visibly. It accumulates fatigue invisibly and then fails all at once.

Do the division and the surprise disappears

Count how many times your garage door opens on a normal day. Out to work, back at lunch, out again, home. A second car doing the same. Someone taking the bins out.

  • Four cycles a day against a 10,000-cycle spring is a little under seven years.
  • Six cycles a day is four and a half.
  • A household where the garage is the front door — which, in most of these neighbourhoods, it is — can clear eight, and that is a three-year part.

People are always startled by this, because a garage door feels like a permanent part of the house, like a wall. It is not. It is the largest moving appliance you own, and it has a consumable in it.

Why the survivor is not the good one

Here is the part that answers the upsell question directly.

On a two-spring door, both springs were manufactured in the same batch, installed on the same afternoon, and have turned exactly the same number of times ever since. They share the load evenly. They have identical fatigue histories.

So when one lets go, the other is not the healthy one. It is the one that happened to have a slightly less unlucky grain of steel. It is at the same point in its life, and it is statistically overdue rather than reliable. In the field the second one typically follows within weeks to a few months.

The practical version: replacing the survivor now costs the spring. Replacing it in February costs the spring, plus a second call-out, plus another evening of a car locked in a garage. It is the same reasoning as replacing both headlight bulbs when one goes, except the failed part weighs enough to matter and the second visit is not a five-minute job.

When we don't replace both

Not every door gets this recommendation, and if a technician gives it to you without looking, that is worth pushing back on.

  • One spring was already replaced recently. Mismatched paint, clean winding cones, a date scrawled on the shaft in marker — there are usually tells. If the survivor genuinely has a few thousand cycles on it, it stays.
  • The door is a single-spring system. Plenty of lighter single-car doors run one spring by design. There is no second one to argue about.
  • The springs are visibly different. Different wire gauge, different length, different colour coding on the cones — that door has been worked on before and the pair are not a pair.

What actually moves the price

We are not going to print a number here, because the honest answer is that it depends on the door and anyone quoting you a figure before seeing it is guessing. But you can work out roughly where your job sits:

  • Door weight and size. A 16-foot insulated double door needs more spring than a single uninsulated one, and heavier springs cost more.
  • One spring or two. Obvious, but it is the biggest single factor.
  • Cycle rating. A 25,000-cycle spring is a modest amount more than a 10,000 and lasts materially longer. On a busy door it is the only genuinely good upgrade on this list.
  • What else the failure took with it. A snapped spring can whip a cable off its drum, chew the drum, or bend the shaft. Sometimes that is a five-minute extra, sometimes it is the bigger half of the job.
  • High-lift or a converted ceiling. Non-standard geometry means non-standard parts.

What not to buy while you are at it

This is the part of the visit where the trade has a reputation, so:

  • You do not need a new door. A snapped spring says nothing about the condition of the door. The panels can be twenty years old and perfectly serviceable.
  • You do not need a new opener. If the opener struggled before the spring broke, that was the spring losing tension, not the motor dying. Get the balance right first, then judge the opener.
  • You do not need the biggest spring available. A spring that is too strong for the door is not a stronger door; it is a door that creeps upward on its own and fights the opener's safety reversal. The right spring is the one matched to the weight.

The upgrade that is actually worth the money is the cycle rating, and it is the least exciting item on the invoice.

The short version

Both springs are the same age, have done the same work, and are the same distance from failing. Replacing the one that broke and leaving its twin is not thrift, it is a deposit on a second call-out.

It is also, we should admit, a spring and an hour — which is a perfectly ordinary repair, and terrible news for anyone hoping to sell you a door.

Garage Door Doctor’Z · (833) 991-3899 · doctorzgaragedoor.com
CSLB C61/D28 · Lic. 1138150 · Serving the Sacramento Valley since 2018.