Garage door extension springs are made specifically for a door height. For example, extension springs for 7' high garage doors generally cannot be used with 8' doors. When you use an extension spring with a taller door, the spring will have to stretch farther to allow the door to close. This affects the lift of the springs as well as how long the spring will last.

Because of the pulley system, the extension spring's stretch is 1/2 of the door height. A common stretch for an 7' high door is 25 X 42.

The 42 indicates that the difference between the spring length when the door is open and when it is closed is 48 inches. Two times 42 inches is 84 inches, which is 7 feet (the door height).

The other number indicated by the stretch of an extension spring is the spring length. In the example above, the 25 refers to a spring length of 25 inches when the spring is compressed.

Though there are often multiple spring lengths for a given door height, longer springs tend to be used on taller garage doors.

Extension springs are also designed to lift a certain amount of weight.

An 80-pound extension spring, for example, will lift 80 pounds.

Because of the pulley system, however, it only lifts 40 pounds of door weight. The extension spring on the other side of the door will lift another 40 pounds. Therefore, two 80-pound extension springs are used on a garage door that weighs 80 pounds.

Garage door extension springs are also color-coded. The lifts for extension springs follow these colors:

This pattern is repeated through all the lift categories. For example, a 90#, a 290#, a 390# and a 490# will all be painted light blue on one end.

All of our overhead door extension and torsion springs are proudly "made in the USA" and include a two year Extended warranty against premature failure

 Use the drop down list to choose the proper weight rated spring for your door

 Don't Know the weight of your door? Disconnect the springs and opener and Use a bathroom scale to weigh the door.