You could call a professional and spend a couple hundred dollars for the repair, in addition to the replacement parts. Or you could do it yourself. If you decide to go that route, you’ll first need to know that there are two types of garage door springs—extension and torsion.

Types of Garage Door Springs

Extension springs

Extension springs are located just above the door tracks that parallel the ceiling, perpendicular to the doors. At one end, they are attached to the rear track hanger; at the other, they attach to one or two pulleys that keep tension on the cables that raise and lower the door. There also should be a second set of safety cables that run through the center of the springs to keep them in place if the springs happen to break. Extension springs function by stretching, thereby keeping tension on the pulley and cables. The pulling weight of extension springs ranges from 50 to 440 pounds. They are also categorized as to their length, typically expressed in inches that equal half the height of the garage door. This type of spring is expected to last for about 10,000 cycles (one opening and closing equals a cycle); you can also buy extension springs with an extended life of up to 20,000 cycles.

Torsion springs

Torsion springs sit above and parallel to the doors. They are mounted in pairs onto a horizontal shaft that’s connected to a cable drum at either end; brackets at each end support the shaft, and a center bracket separates the pair of springs. Instead of stretching, torsion springs work by tension. They are installed under tension—wound up tightly on the shaft. When the garage door opens, the tension is gradually released, and the spring is unwound. When the door is closed, the springs are put back into tension again. Torsion springs generally have a longer service life than extension springs, averaging 15,000 to 20,000 cycles. Both types of springs are color-coded with a touch of paint at either end to indicate their pulling strength and their length, which should be matched to the weight and height of the garage door.

How to Replace an Extension Spring on a Garage Door

When a spring breaks or has lost its tension, it must be replaced, and while you’re at it, you might as well replace its partner spring on the other side of the door.

How to Replace a Torsion Spring on a Garage Door

Torsion spring replacement is technically more difficult than that of extension springs and can be dangerous. If you’re not confident in your abilities, call a professional.

Materials

A sturdy stepladder Work gloves

Tools

How to Replace a Garage Door Spring - 7How to Replace a Garage Door Spring - 92How to Replace a Garage Door Spring - 47How to Replace a Garage Door Spring - 78