Why is my garage door bending in the middle when it opens?

A garage door that bows or folds in the middle as it rises is being pushed or pulled unevenly, or has a section that is too weak for the load. The usual causes are a missing or weak reinforcement on the top section, an opener arm pulling at the wrong point, a bent or loose hinge, worn rollers or bent track. Stop using the door and have a licensed garage door pro find which one it is.

What usually causes a door to bend

The opener is pulling on an unreinforced section. The opener pulls on a single point at the top of the door. Clopay's manual for its aluminum full-vision door says you must reinforce the top section of the door in order to provide a mounting point for the opener to be attached.^[1] Other makers' doors have their own requirements. If that reinforcement was never fitted, or has come loose, the top panel flexes every time the opener starts and the door appears to fold near the middle of its travel.

The opener rail is set at the wrong distance. The same manual says that, on that door, to prevent the top of the door from bending, the opener rail should be mounted no less than 2" and no greater than 5" from the face of the door with the door in the open position.^[1] A rail that is too close or too far changes the angle of the pull and bends the top of the door.

A hinge is bent or loose. The sections fold at their hinges. Clopay's maintenance steps list loose or bent hinges as something to check, with the instruction to "Straighten or replace bent hinges" for the technician.^[1] One failed hinge lets two sections twist against each other instead of moving together.

A roller is worn or has left its track. Broken wheels, bent shafts and worn bearings let one side of a section drag or tilt. The door then racks, with one side higher than the other, which looks like a bend through the middle.

The track is bent. Clopay's maintenance steps include checking for bent track and say, "If bent, call an authorized professional dealer".^[1] Track that has been bumped by a car or has loosened from the wall changes how the door travels.

A panel is cracked or has lost its stiffness. Thin steel, aluminium or old composite sections can crease where a dent or crack has weakened them. If one section is the problem, the sibling answers cover whether a single panel can be replaced and whether to replace one panel or the whole door.

The springs are out of balance. If the springs no longer match the door's weight, the opener does more of the lifting and the door strains. CPSC warns that a severely unbalanced garage door could unexpectedly crash to the floor possibly striking someone under the open door.^[2]

What you can safely do while you wait

You can look, but not fix. From a safe distance, watch the door move once and note where the bend appears: near the opener arm, at one side, or at a visible crack. Take a photo or short video. Check whether anything is rubbing, such as a stored item against the track.

Then stop using the opener. If the door has to be closed, close it and leave it. Keep people and cars out from under it while it is raised.

Why this is not a home repair

Several of the likely causes involve parts that are dangerous to touch. Clopay says that springs, cables, and bottom fixtures are under strong spring tension.^[1] Even a simple hinge swap has a rule behind it: Clopay's manual warns: No more than one hinge is to be removed from the door at any given time.^[1] Mounting the opener correctly, reinforcing a top section and straightening track all depend on knowing how the door is balanced.

CPSC adds that if doors are not "balanced," or if they bind or stick, they should be serviced by a professional.^[2] A door that flexes as it moves is showing one of those signs. For the safety checks a technician should include, see how often a garage door should be serviced and how to know if a garage door spring is broken.

What the repair involves and what it costs

The fix depends on the cause. A technician may add reinforcement to the top section, reset the opener rail, replace hinges or rollers, realign or replace track, replace a damaged section or, on an old door, recommend replacing the whole door. Each of these has a different price, so there is no single figure. Ask for a written quote that names the part being repaired, the parts used and the labour, and a second quote for replacing the section or door if the repair is large. For section pricing, see how much a single garage door section costs in Virginia.

When to call a licensed pro

Call before you use the door again. This is pro-only work because of the spring tension, the weight of the door and the way the opener loads it. In Virginia, if the work you are considering is valued at $1,000 or more, a valid Virginia Contractor's License is required for the license category in which the contractor is to work.^[3] Smaller repairs are still best left to a trained technician, and you can check any licence with the Department of Professional and Occupational Regulation before you agree to the job. Tell the pro where the bend appears, when it started and whether the door was recently hit, repaired or fitted with a new opener.

Loclis lists licensed local pros under garage doors, and there are more garage door answers. To get the door inspected, describe the problem once and local pros will quote it.