The door drops like a stone because the counterbalance system has failed. A torsion or extension spring has snapped, or a lift cable has parted, and the door’s full weight — 150 to 300 pounds on a typical residential panel — is now running on gravity alone.
Do not try to catch it. Do not stand under it to pull the emergency release. Clear the opening, keep kids and pets out of the garage, and call a repair company that carries residential springs and cables on the truck.
What just happened inside the system
Most residential doors use one of two counterbalance designs. Torsion springs sit on a steel shaft above the opening, wound tight. Extension springs run parallel to the horizontal tracks, stretched out. Both store enough energy to lift the door. When a spring breaks, that energy releases in a fraction of a second. The door accelerates down and hits the floor with the force of a falling safe.
A cable failure produces the same result. The cable drums on a torsion system, or the pulley forks on an extension system, lose their wrap. The door skews, one side drops faster, and the panels bind in the tracks. You will often hear a loud bang — the spring snapping or the cable whipping — followed by the crash.
Why the opener could not stop it
The operator is not a brake. It is a motor and a drive gear (or chain/belt) rated to move a balanced door. When the counterbalance disappears, the door becomes a dead weight that exceeds the opener’s lifting capacity by three or four times. The safety reversal system — photo eyes and force sensing — only works while the door is moving under the opener’s control. A free-fall is faster than the logic board can react.
Pulling the red emergency cord while the door is moving adds slack to a system that already has none. The door will still fall. The only difference is you are now standing closer to it.
Make-safe steps you can take right now
1. Block the opening. If the door is fully down, leave it there. If it stopped partway, do not reach under it. Place a 2×4 or a stepladder on its side across the threshold so no one walks or drives into the gap. 2. Disable the opener. Unplug the power head from the ceiling outlet. If the outlet is not accessible, flip the breaker labeled “garage” or “opener.” 3. Do not disconnect the arm. The curved door arm connecting the trolley to the top panel is the only thing keeping the door from sliding the rest of the way down if it is stuck halfway. Leave it pinned. 4. Secure the door if it is fully closed. A C-clamp or locking pliers on the vertical track, just below the bottom roller, prevents the door from being lifted by wind or by someone pulling the release cord from outside. 5. Call a company that stocks residential springs and cables. Same-day service is standard in Metro Vancouver when the truck carries the parts. Ask what they carry before you book.
What the repair actually involves
A broken torsion spring means replacing both springs on the shaft. They are sold in matched pairs rated for cycle life — 10,000, 25,000, or 50,000 cycles. Installing a single new spring against an old one unbalances the shaft and shortens the life of the new unit. The technician unwinds the remaining spring, removes the shaft, swaps the springs, re-centres the bearing plates, and winds to the door’s specific turn count. Cable replacement follows the same logic: both sides, new drums if the grooves are worn, and the bottom brackets inspected for cracking.
Extension spring doors get a pair of new springs, new safety cables threaded through the centre of each spring, and new pulley forks if the bearings are gritty. Safety cables are not optional. They catch the spring when it breaks so it cannot whip across the garage or through a windshield.
Both repairs take one to two hours on a standard 7-foot or 8-foot residential door. High-lift or vertical-lift track conversions take longer because the spring sizing changes.
What you will see on the invoice
- Two springs (torsion) or two springs plus safety cables (extension)
- Labour for removal, installation, winding, and balance test
- Hardware: cones, cables, drums, or pulleys only if the originals are damaged
- No charge for the service call if the repair is approved
A flat-rate quote is presented before any wrench turns. The door is tested through a full open-close cycle, the opener force and limits are reset, and the photo eyes are verified. You get a two-year workmanship warranty on the repair.
How to keep it from happening again
Springs fail on cycle count, not calendar years. A 10,000-cycle spring on a door used four times a day lasts about seven years. The same spring on a door used twice a day lasts fourteen. You cannot see the fatigue from the outside.
What you can do:
- Lubricate the coils twice a year with a non-sticky garage door spray. Dry coils rub, heat up, and snap sooner.
- Watch the gap. A torsion spring with a visible gap between coils is already broken. An extension spring with a stretched-out hook is near the end.
- Listen. A loud “twang” or a door that suddenly feels heavy on the way up is a spring losing torque.
- Schedule replacement before failure. If the springs are original to the house and you have no receipt showing a swap, they are on borrowed time.
When to call
The door is on the floor and will not rise. The door is crooked in the tracks. You heard a bang like a gunshot from the garage. The opener runs but the door does not move. Any of these means the counterbalance is gone. Up and Down Garage Doors carries residential torsion and extension springs, lift cables, drums, and pulleys on every truck. Call 778-873-7282 or email info@upanddowngaragedoors.ca for a same-day flat-rate quote.