Garage door cables look simple — a length of galvanized aircraft wire on each side, looped around a drum at the top of the door — but they do the heaviest lifting in the whole system. When one fails, the other is usually close behind. A snapped cable while the door is moving is a common garage door emergency we handle daily across Ottawa.
Signs of a cable problem
- Door hangs visibly crooked — one side higher than the other
- Loud snap or pop from the garage, then the door becomes hard to lift
- Cable visibly frayed, broken, or hanging loose
- Cable came off the drum (the spool at the top corner of the door)
- Door grinds, scrapes, or stops mid-travel
- Visible kink or stretched section in the cable
Stop using the door immediately if you see a broken or frayed cable. A door with a failed cable can drop without warning — it's one of the most common causes of garage door injuries. Disconnect the opener (red rope) and call us.
Why we recommend replacing cables in pairs
Both cables on your door are the same age, made the same week, exposed to the same Ottawa winters, and rated for the same number of cycles. When one snaps, the other has usually used up much of its useful life. Replacing only the broken cable often means a second service call within months — that's why we generally recommend doing both at once and quote it that way.
How a cable repair works
- Secure the doorWe lock the door in place with vise grips on the tracks before any work starts.
- Release spring tensionCables can only be replaced safely with the springs at zero tension. This is the step that hurts DIYers.
- Replace both cablesHeavy-duty galvanized aircraft cable, sized to your door's weight. We use 7×19 stranded cable rated well above your door's load.
- Re-balance and re-tensionSprings are wound back to spec and tested. A properly balanced door should stay open at half-height on its own.
- Cycle test and clean upFull open/close cycles, hinge and roller lubrication, and we haul away the old cables.
Real cable work — before & after
How long should cables last?
A quality 7×19 galvanized cable on a residential door should last 10–15 years under normal use (3–5 cycles per day). They fail earlier when: the door is unbalanced and the cable is doing the spring's job too; the cable rubs against a bracket or pulley; or salt and humidity from winter slush rust the strands from the inside. Annual lubrication of the drum and pulleys roughly doubles cable life.