How to Fix Sagging Garage Door Binds

Close the sagging garage door. Skip to step eight if the door has an installed bracing kit.

Hook the end of a chalk line on one bottom corner of the door. Pull the chalk line at a diagonal to the door's top corner. Snap the chalk line to mark the door. Repeat the process to create a second diagonal line. Ensure the chalk line sits below the center locking bar to provide the best lines.

Push one end of a tape measure under one corner of the door. Pull the tape measure along the diagonal line to the top corner. Read the measurement of the first diagonal. Measure the length of the second diagonal using the same method. Place a pencil mark on the line with the longest diagonal measurement.

Hold one bracket of a garage door bracing kit against the inside face of the door with the larger center hole aligned with the chalk line. Mark the location of each bracket hole on the door with a pencil. Locate and mark all mounting brackets using the distances recommended by the bracing kit manufacturer.

Set the tip of an awl on one of the marked mounting holes. Strike the back of the awl forcefully to create a starting hole for a drill bit. Make a starting hole at each marked location. Secure a drill bit in a drill that matches the size specified in the bracing installation instructions. Drill a hole through the door at each awl hole. Drill slowly to avoid damaging the exterior surface of wood garage doors.

Have an assistant push a carriage bolt -- supplied with the bracing kit -- through a set of mounting holes. Slide the bracket over the carriage bolts. Thread a supplied hex nut on the end of each bolt. Turn each nut clockwise with an adjustable wrench. Install the remaining five brackets using the same method.

Slide one supplied tension rod or cable through the bottom set of mounting brackets. Secure the rod to the brackets using the method described in the bracing kit installation instructions. Secure the top tension rod or cable using the same method.

Subtract the shortest diagonal measurement from the longest diagonal measurement measured in step three. Divide the difference by two. Add the remainder to the shortest length. For example, a short measurement of 139.5 inches subtracted from a long measurement of 140 inches would leave a difference of 1/2 inch. Divided by two, the amount would equal 1/4 inch. Add 1/4 inch to 139.5 for a distance of 139.75.

Pull the tape measure along the shortest diagonal line. Turn the tension rod or cable turnbuckle clockwise with a flathead screwdriver until the tape measure reads the calculated distance. Open the garage door. Adjust the tension rod in short distances if the door binds in the tracks.