Garage Door Springs & Cables

How the Counterbalance System Actually Works

Your opener is weaker than you think — most residential units pull with roughly the force needed to lift a few dozen pounds. The door itself weighs 150-400 pounds. The difference is made up by the counterbalance system: springs that store energy when the door closes and release it as the door opens, so at every point in its travel the door is nearly weightless. When the system is balanced, you can lift the door with one hand and it will hover halfway without drifting. That hover is the whole idea, and everything in this hub follows from it.

Two spring designs do this work. A torsion spring mounts on a shaft above the door and twists as the door closes; cables wound on drums at the shaft's ends connect that twist to the door's bottom corners. Extension springs mount alongside the horizontal tracks and stretch instead, pulling through pulleys and cables. Both systems end at the same place — the bottom brackets, where the cables attach — and both depend on every part being sized to the door's actual weight. A spring that is one size off doesn't fail dramatically; it just makes the door heavy or light, works the opener harder, and dies young.

Torsion vs. Extension Springs

Torsion systems are the modern standard for good reasons: they balance the door from the center shaft, so both sides lift evenly; they contain their energy on the shaft when they break, instead of snapping back along the track; and they typically outlast extension springs. When a torsion spring breaks, you'll often find it in two pieces with a visible gap in the coil — and the door simply refuses to open, because half (or all) of its lift is gone.

Extension springs are common on older and lighter single doors. They must run with safety containment cables threaded through them — if you can see extension springs without a cable through the middle, that missing cable is a genuine hazard to correct at the next service. Extension springs also stretch and fatigue unevenly, which is why a door on old extension springs often rises crooked in its last year. Converting an extension setup to torsion is possible on most doors ($300-$500) and is worth discussing when the door is heavy, the springs are failing repeatedly, or the tracks have room for the shaft hardware.

For the full side-by-side — cost, lifespan, safety and the conversion math — read our torsion vs extension springs guide.

Cycle Life: The Number That Decides When Yours Breaks

Springs don't wear out by calendar — they wear out by count. One cycle is one open plus one close, and a standard spring is engineered for about 10,000 of them. Do the household math: a family that uses the garage as its front door might run 4-6 cycles a day, which spends a standard spring in five to seven years. A household at 8+ cycles a day can spend one in three and a half. This is why two identical houses on the same street can have springs that fail a decade apart.

Our guide on how long garage door springs last covers the full picture — the signs a spring is in its final season (rust blooms, visible stretch, a door growing heavier and louder), and the high-cycle upgrade that changes the math: springs rated 25,000-50,000 cycles cost $50-$150 more installed and can triple the interval between replacements. For a high-use household, the upgrade isn't an upsell; it's the difference between a repair and a subscription. When you get a spring quote, ask for the cycle rating in writing — a company that sized the spring to your door knows the number offhand.

Why Springs Are Replaced in Pairs and Sized to the Door

Most double doors run two torsion springs, and when one breaks, the survivor is the same age, has run the same cycles, and is statistically in its final stretch. Replacing only the broken one saves perhaps $80 today and buys a second service call — often within the year — for the other. Replacing the matched pair resets the whole system: both springs share the load evenly, balance is exact, and the labor overlaps almost completely. This is one of the few 'while you're in there' recommendations in home repair that survives scrutiny.

Sizing matters as much as pairing. The correct spring is chosen from the door's weight — a technician weighs the door or works from its make, size, and construction — and expressed in wire gauge, inside diameter, and length. An undersized spring leaves the door heavy: the opener strains, gears wear, and the spring itself overworks and fails early. An oversized spring makes the door hot — it wants to fly up and won't stay down — which is hard on every hinge and roller. If a previous replacement was sized by eyeball, an early second failure is usually the receipt. For the full pricing picture, our spring replacement cost guide breaks down what each configuration costs and why.

What Spring and Cable Work Costs

Pricing in this system is standardized enough to publish. These ranges come from 2026 national data (Angi / HomeAdvisor) and match the quotes we write daily; the full umbrella view, covering every job on the site, lives in our garage door costs & pricing hub, and the complete repair breakdown is in the 2026 garage door repair cost guide.

Job	Typical Cost	Notes
Single torsion spring	$120-$250	Standard single or light double door
Torsion spring pair	$200-$350	Recommended — matched age and balance
Extension spring pair	$120-$280	Includes safety containment cables
Cable replacement (pair)	$80-$185	Often paired with spring work
High-cycle spring upgrade	+$50-$150	25,000-50,000 cycle rating
Extension-to-torsion conversion	$300-$500	Full system change

What's inside those numbers: the spring itself is often a $60-ish part; the rest is the skilled labor of handling stored energy safely, plus balancing, cable and drum inspection, and the safety tests that close every job. Compare quotes on the installed total and the cycle rating — the two numbers that determine what you actually bought.

The Safety Case: Why This System Is Professional-Only

Every hub on this site is happy to explain DIY checks — except this one, and the reason is physics. A wound torsion spring holds enough energy to lift a several-hundred-pound door; released carelessly, it releases that energy into whatever is holding the winding bar. Spring and cable work accounts for a disproportionate share of garage door injuries precisely because the parts look simple: a coil, a cable, a few bolts. The procedures that make it safe — proper winding bars, vise-grip discipline, never standing in the bar's path, taking tension off before touching cable hardware — are technique, not caution theater.

So the honest division of labor: you do the watching (the quarterly ten-second cable check in our troubleshooting hub catches fraying in the cheap stage), and a technician does the touching. A professional spring visit also covers what a spring-only swap misses: bearing plates that grind, drums that slip, cables at their fray point, and a final balance test proving the door hovers where it should. If your door has made its loud bang, keep it closed, keep the opener off, and call (210) 964-8892 — spring replacement is $120-$350 and is normally completed the same day, with the door balanced and safety-tested before we leave.

Cables: The Quiet Half of the System

Cables get half the attention and cause a memorable share of the drama. Each cable runs from the door's bottom bracket up to its drum, winding and unwinding with every cycle. They fail by fraying — individual strands breaking over months, usually where the cable bends around the drum or rubs at the bottom bracket — and by rust, especially in humid climates and coastal air. A frayed cable still works, right up to the cycle where it doesn't, and when it lets go, that side of the door drops until the other cable or the track catches it: the classic crooked-door photograph.

The defenses are cheap. Look at your cables quarterly with the door closed: strands sticking out like frayed rope, rust color bleeding through, or one cable hanging looser than its twin are all early warnings, and replacement at that stage is a calm $80-$185 appointment. Never touch a frayed cable — it is still carrying spring load — and don't run the door 'one more time' to test it. Cable work is also why spring jobs inspect the whole lifting path: a new spring winding a frayed cable onto a worn drum is a repair with the cause left in. Our cable replacement service page covers what a proper cable visit includes.

Springs in Our Service Climates: Rust, Humidity and Cold

The same spring lives a different life in San Diego than in Worcester. Salt air along the coast works on bare steel year-round, and a spring that would run a full decade inland can show rust blooms in half that time near the water — which is why galvanized and coated springs earn their modest premium in coastal zip codes. In the humid Southeast and Gulf side of Texas, summer moisture plus a hot garage accelerates the same corrosion chemistry, and springs there tend to announce their final season with visible rust at the coils' contact points.

Cold climates attack from the other direction: steel loses a measure of its toughness in deep cold, and the January failure spike every garage door company knows is partly metallurgy and partly math — doors get used harder in the holidays, lubricants thicken, and a spring already at 9,800 of its 10,000 cycles picks the coldest morning to finish the count. The practical takeaways travel well across all ten of our states: keep springs lightly oiled (a garage-door lubricant, never grease, which collects grit), treat rust blooms as a scheduling signal rather than a cosmetic flaw, and if your spring is visibly aged heading into winter, a planned replacement in the calm season beats an emergency call in the peak one — same spring, same price band, better calendar.

Services: Garage Door Springs & Cables

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