Most people don’t know how to measure garage door torsion springs properly. If you ever need to replace a broken garage door springs you will need specific information to correctly purchase a replacement. Unless you know the specific model, size and brand of garage door you will need to measure the broken torsion spring yourself. While most garage door dealers can measure broken torsion springs in the store, you may need to learn how to measure springs yourself if you don’t feel like bringing in the broken spring. Always have this information available when talking to a garage door professional. Improper spring measuring can lead to poor door performance or personal injury.
Length
Measuring the length of the spring is the easiest part of the process. Simply lay the torsion spring down on a table, combining the two pieces together. Do not measure the gap between coils where the spring has broken or the end cones. Lay a tape down at one end of the spring and measure coil to coil not including the cones. If you find yourself measuring a spring that is on the garage door and has tension on it measure the coil only and subtract 2-4 inches. Wound springs are under tension and stretch out.
Wire Size
Next, measure the thickness of the coil on the spring. The wire size can be measured easiest with a spring gauge. If you do not have a spring gauge available take a 10-count or 20-count measurement of the coil. Lay the tape on top of the spring, wedging the end of the tape in between the coil. Count 10 coils and record the length using inches. Once you have this measurement you can use the chart below to find your wire size. Always be as precise as possible when taking measurements. If you are unsure of yourself use a 20-coil count for greater accuracy.
Inside Diameter
Inside diameter is the measurement of the hollow inside part of a spring. Torsion springs come in a variety of widths, from 1 3/4 inches to 6 inches for commercial springs. Generally, larger inside diameter springs are used for commercial garage doors. Smaller diameters of 1 3/4, 2 inch, and 2 1/4 are used on residential garage doors.
Left Wound or Right Wound?
Holding the torsion spring vertically it is easy to see what wind of spring you have. The end of the torsion spring points in the direction of the wind. You can alternatively look at the color coding on the cones of the springs. Black paint means the spring is left wound while red paint means the spring is right wound. When you are inside your garage looking at the springs the right wound spring will be on the left side of the center plate, while the left wound spring with be mounted on the right side for standard lift garage doors. If you have special low headroom track the opposite holds true.
Spring Ordering Format
When ordering a garage door torsion spring always have these specifications available. A professional garage door dealer will have charts readily available if you provide coil counts instead of using a spring gauge measurement. If the inside diameter of the torsion spring(s) you have don’t match what is at the dealer, he or she can convert the spring to a diameter they have in stock. Doing so will increase or decrease the length of the spring. You can also request high cycle torsion springs if you plan on using your overhead door frequently.
- Quantity (single or pair)
- Wire Size (10 coil count)
- Length (inches)
- Inside Diameter (inches)
- Wind (R or L)
Example: (1) .218 x 25″ x 1.75″ RW
I write tutorials about garage door repair, installation and maintenance. With over a decade of experience in the overhead door industry I’ve learned a lot and I’d like to share my knowledge with you.