Why did my garage door make a loud bang in summer?

What that loud bang actually means

If your garage made a loud bang and now the door won't open (or opens crooked), you almost certainly broke a torsion spring. It's the single most common cause of that sound, and it's not subtle.

The bang is the spring releasing its stored energy the instant it snaps. People describe it as a gunshot, a firecracker, or something falling off a shelf. It's loud enough to wake the house.

Here's the good news: a broken spring doesn't mean your door is ruined. It's a routine wear part, and a good tech swaps it in under an hour.

Here's the part people get wrong: they hit the opener button to test it. Don't. If the spring is broken, the opener is now fighting the full weight of the door and you can cook the motor.

Summer gets blamed a lot, and it does play a role, but the real cause is age and use. The heat just picks the day.

The most likely causes, ranked

in most cases, that bang is a torsion spring. It's the long coiled spring mounted on a steel bar above the door opening. Look for a one to two inch gap where the coils separated.

If your door is older or a lighter single-car style, you might have extension springs instead. Those run alongside the horizontal tracks near the ceiling. A broken one hangs loose.

A snapped lift cable makes a similar bang and often leaves the door hanging crooked, with one side higher than the other. The cables are the steel wires running from the bottom corners up to the drums.

Less often, a brittle plastic roller cracks or a track bracket works loose from the framing. Those bangs are usually quieter and the door still moves, just roughly.

The pattern that tells you it's a spring: loud bang, then the door either won't move at all with the opener or feels impossibly heavy by hand.

Why summer triggers spring failures

Springs don't care what month it is. They care how many times they've been cycled. A standard spring is rated for about 10,000 open-close cycles, and every trip counts down that number.

So why do so many break in summer? Two reasons, both about temperature.

First, an uninsulated garage can swing from 70 degrees at dawn to over 110 by afternoon. Steel expands and contracts with those swings, and a spring near the end of its life fails during that stress.

Second, summer is when the door gets used most. Kids in and out, mowing, hauling gear to the car. More cycles in a short window pushes a tired spring over the edge.

If your garage bakes in the sun and has no insulation, you'll see faster spring wear than a neighbor with a conditioned garage. It's worth knowing when you're deciding on cycle rating for the replacement.

What to do right now

Start by leaving the door alone. If it's closed, keep it closed. If it's stuck partway, don't stand under it.

Walk into the garage and look at the spring above the door. A clean gap in the coils confirms a broken torsion spring. If the springs run along the tracks instead, check those.

Note how many springs you have (one or two) and whether they look the same age. This helps a tech quote you accurately over the phone.

Resist the urge to run the opener. One test cycle against a broken spring can be enough to damage the motor or bend a panel.

If you absolutely need a car out and the door is fully down with a totally dead spring, get two strong adults to lift it and clamp it open on the track. Otherwise, wait for the tech.

Then call a licensed garage door company. Ask for a same-day or next-day slot; most reputable outfits handle spring breaks quickly because they know the door is out of service.

• Keep the door closed if you can
• Confirm the broken spring visually
• Count your springs and note their size
• Don't run the opener
• Call a licensed pro

What it costs in 2026

A professional spring replacement runs $150–$500 for a typical two-car door with two springs done as a pair. That's the honest all-in range including parts, labor, and the trip.

The springs themselves aren't expensive. A single torsion spring costs $40 to $80. What you're paying for is the labor and the specialized (and genuinely dangerous) skill of winding tensioned steel safely.

If you have a two-spring setup and only replace one, you might see a quote closer to $250 to $350. But most techs will (rightly) push you to do both, since the second is the same age.

Higher-cycle springs, oversized or solid-wood doors, and adding new cables or rollers push you toward the top of the range or a little past it.

For torsion springs, the pro cost is money well spent.

• Single torsion spring (part only): $40 to $80
• Two-spring replacement with a pro: $150–$500
• Upgrade to 20,000+ cycle springs: add $50 to $120
• Add new lift cables during the job: $40 to $90
• Emergency or after-hours service: add $75 to $150

DIY vs calling a pro

This is one of the few repairs where I'll flatly tell a handy homeowner to step back. Torsion spring work sends people to the ER every year.

The danger is in the winding. A torsion spring gets wound with steel bars to an exact turn count. If a bar slips or you lose your grip, that bar or the spring becomes a projectile.

Extension springs are a notch less deadly but still carry serious force, especially if the safety cable is missing or degraded.

What you can safely do yourself: identify the broken part, count your springs, clear the area, and lube the rollers and hinges once the repair is done.

What you should leave to a licensed tech: any spring replacement, cable replacement, and rebalancing the door. The tools and the turn-count knowledge matter more than raw handiness here.

Can you wait to fix it?

A broken spring is low urgency for your safety only if you leave the door alone. The risk comes from using it, not from a closed door sitting there.

That said, you should get it fixed within a few days for practical reasons. A garage with a dead door means no vehicle access and, in most homes, a locked-out side entrance.

If you have two springs and only one broke, the door might still limp along on the survivor. Don't rely on that. The remaining spring is now overloaded and will fail soon, possibly while the door is up.

The real cost of waiting is escalation. Keep running the opener and you'll add a burned-out motor or a bent panel to the bill.

Bottom line: no emergency if you stop using the door, but book the repair this week.

Safety first, always

Garage door springs hold more stored energy than almost anything else in a typical home. Treat them with respect.

Never put your hands, a tool, or your face near a wound spring. A spring that looks intact can still be under full tension and let go if disturbed.

If you're using the manual release to disconnect the opener, only do it with the door fully closed. Pulling the release on a raised door with a broken spring drops the whole weight instantly.

Keep kids and pets clear of the door until the repair is done. A door off track or on a failing second spring is unpredictable.

When the tech is done, ask them to test the door's balance. A properly balanced door should hold in place when lifted halfway by hand.

How a pro actually fixes it

Knowing the process helps you spot a good tech from a bad one. Here's what a proper spring job looks like.

The tech releases any remaining tension safely, then unwinds and removes the old springs using winding bars. They'll measure the wire size, inside diameter, and length to match the correct replacement.

New springs go on the torsion bar and get wound to the exact turn count for your door's weight and height. Too few turns and the door won't stay up; too many and it flies open.

They should check and lube the cables, rollers, and bearings while they're in there, since those age alongside the springs.

Finally, they balance-test the door by hand and cycle it with the opener a few times. A quality tech won't leave until the door holds halfway and runs smooth.

If a tech quotes a spring swap without measuring the wire or asking about door weight, that's a red flag. The wrong spring size fails fast or wears the opener.