What Is a Garage Door Torsion Spring?
A torsion spring is a tightly-wound coil of high-tensile steel mounted on a metal shaft directly above your garage door opening. When you close the door, the spring winds up and stores energy. When you open the door, that stored energy unwinds and does the work of lifting — making a 200-lb door feel like it weighs almost nothing to your opener motor.
Without a functioning torsion spring, your opener motor would be trying to lift the full dead weight of the door — which is why openers strain and sometimes burn out when a spring breaks. The opener is designed to move a balanced door, not to be a crane.
Torsion vs. Extension Springs — Which Do You Have?
🌀 Torsion Springs
- Horizontal bar above the door
- 1 spring (single door) or 2 springs (double)
- Wind around a central shaft
- Standard in most homes built after 1990
- Safer, longer lifespan, smoother operation
- More expensive to replace ($150–$350)
📐 Extension Springs
- Run along the sides of the door tracks
- Stretch horizontally as door closes
- Common in older homes and low-clearance garages
- Less expensive but less safe without safety cables
- Replace as a matched pair ($120–$220)
How to Measure Your Torsion Spring
If you need to order a replacement or describe your spring to a technician, you'll need four measurements. Never attempt to remove the spring to measure it — measure while it's in place with the door closed and spring fully wound.
| Measurement | How to Find It | Example |
|---|---|---|
| Wire diameter | Measure 10 coils, divide by 10 (use calipers) | 0.225" common for double door |
| Inside diameter | Measure the inside of the coil | 2" standard, 1.75" for lighter doors |
| Overall length | End to end of the entire spring | 24"–36" typical |
| Wind direction | Right-wound: coils go right at near end. Left-wound: opposite. | Double doors use one of each |
Torsion Spring Cycle Life — How Long Will Yours Last?
| Spring Rating | Cycles | Est. Lifespan (4 opens/day) | Cost Difference |
|---|---|---|---|
| Standard | 10,000 | ~7 years | Base price |
| High-cycle Recommended | 25,000 | ~17 years | +$50–$100 |
| Extended high-cycle | 50,000 | ~34 years | +$100–$175 |
⚠️ Why Torsion Spring Replacement Is Not a DIY Job
Torsion springs store enormous energy — a standard residential spring stores 200–400 ft-lbs of torque. When winding or unwinding a spring, the winding bars are under this full load. A bar that slips fires across the garage at lethal velocity. Professional technicians use proper hardened steel winding bars (not screwdrivers or rebar) and specific winding sequences built up over years of practice. The $150–$350 repair cost is worth every dollar for this job.