How long do commercial garage doors last?

A commercial garage door lasts as many open and close cycles as its parts can take, not a set number of years. The door sections or steel curtain usually outlast several sets of springs, cables, rollers and operator parts. So the useful question is how many times a day your door runs and which part will wear out first. A door that runs 10 times a day can go many years between spring jobs. The same door at a busy dock running 60 times a day can need springs within a year on a standard spring.

Why a commercial door's life is counted in cycles

The industry test for door life counts cycles. The standard test method, ANSI/DASMA 109, defines one cycle as the door moving from closed to fully open and back to closed. It runs the whole door system, frame and anchors included, until it reaches a set number of cycles or fails, and failure "may involve any component of the door system." That is the point for a building owner: the door is only as long-lived as the part that gives out first.

The spring is usually that part. DASMA's sheet on factors affecting spring cycle life notes that spring cycle life may not match door cycle life. A spring has its own rating, and when it reaches it, the door stops even if every panel is sound.

How to work out your door's life from its daily use

Divide the part's cycle rating by the cycles your door runs in a day. That gives the number of working days the part should last.

• Count a normal day. Some commercial operators show a cycle count in their settings. If yours does not, count the openings on one busy shift and multiply by the shifts you run.
• Find the spring rating. A technician can read it from the spring size and the door weight, or from the paperwork left at installation.
• Do the division. A 10,000 cycle spring at 20 cycles a day lasts about 500 working days. At 60 cycles a day it lasts about 170 working days. A spring rated for five times as many cycles stretches each of those five times.
• Count working days, not calendar days. A dock that runs six days a week uses its springs faster than an office door that runs five.

Doors that run all day are often fitted with longer springs made for more cycles. See our guide to high-cycle garage door springs for how those ratings work.

Which parts wear out first on a commercial door

• Springs. They carry the door's weight on every cycle and break from metal fatigue. A broken spring leaves the door too heavy to lift.
• Cables and drums. On a sectional door, the cables lift the door from the bottom corners. Fraying near the bottom bracket is the warning sign.
• Rollers and bearings. Worn rollers get loud and rough, and a worn bearing in a rolling door's headplate bracket makes a grinding noise.
• The operator. Limit switches, drive chains, belts, gears and brakes wear with use. An operator that strains to lift the door is often carrying a spring problem as well.
• Safety devices. Photo eyes and edge sensors take hits from carts and forklifts and should be tested often.
• Weather seals and the bottom bar. They wear from contact with the floor and from trucks backing into the opening.
• Slats and end locks on rolling steel doors. A bent slat or a loose end lock makes the curtain bind in its guides.

What shortens a commercial door's life

DASMA's spring cycle life sheet lists the most common reasons a spring fails early, and most of them apply to the whole door:

• The wrong spring for the door. A spring that does not match the door's counterbalance needs can shorten the life of both the door and the operator.
• The wrong number of turns. Too much tension puts extra force on the other counterbalance parts. Too little lets the door drift down from the open position.
• A door heavier than it was built for. Paint, signs, insulation or added hardware raise the weight past the spring's design. DASMA warns against adding weight to a garage door.
• Doors left open in harsh weather. A door that stands open for long stretches leaves its springs exposed to heat, cold and moisture. DASMA advises keeping doors closed where possible in extreme climates.
• Corrosive air. Cleaning chemicals that contain chlorine, as in wash bays, can corrode springs and lead to early failure.
• Skipped maintenance. Springs and the counterbalance should be lubricated and serviced as the door maker's instructions say.

Hits from forklifts and trucks are the other big cause. A bent guide or a dented section makes every later cycle harder on the springs and the operator.

What your staff can check between service visits

DASMA publishes a checklist for building maintenance supervisors, its recommended rolling door maintenance practices. It says staff should never adjust the spring tension wheel, and it lists signs that mean a call for service:

• The door will not stay in the open position and has to be propped.
• Opening it by hand takes more than 35 pounds on a hand chain or 25 pounds on a crank.
• The tension wheel or tension shaft turns while the door runs.
• A bearing looks or sounds worn.
• The electric operator sounds like it is straining. The sheet says to check electric doors this way every quarter.

The same sheet says to test the door's sensing devices at least weekly, at both ends of the sensing edge. Small faults found this way cost far less than a door that stops with a truck at the dock. For a fuller schedule, see how to prevent commercial door downtime.

Repair the part or replace the door?

Most commercial doors are worth repairing when the trouble is a spring, cable, roller, bearing or operator part. Those parts are made to be replaced, and a new door does not fix a worn spring. Replacing the door starts to make sense when:

• Several sections or many slats are bent, cracked or rusted through.
• The guides or the frame have been hit so often that the door will not stay aligned.
• Parts for the door are no longer made.
• The business has changed and the door no longer fits the job, such as a dock that now needs a faster or better insulated door.

Our commercial garage door installation page covers what a replacement involves.

Questions about commercial garage door life

How often should you replace a commercial garage door?

There is no fixed schedule. Replace the parts as they reach their cycle life, and replace the door when the sections, the curtain or the frame are past repair. A well-kept door outlives several sets of springs.

How long do commercial garage door springs last?

As long as their cycle rating allows at your door's daily use. Divide the rating by your daily cycles to get working days. A busy dock door on standard springs can need new ones within a year.

Is it worth repairing an old commercial door operator?

Often, if parts are still made and its safety devices work. An old operator may lack the monitored safety devices newer ones carry, so it is worth having it checked before you spend on it. See commercial garage door operators.

What does it cost to replace a commercial garage door?

It depends on the size, the door type, the insulation, the operator and the opening. Read what drives commercial garage door cost, then get a quote for your own building.

How G Brothers helps

G Brothers repairs and installs commercial garage doors, including rolling steel, sectional, high-cycle and fire-rated doors, for warehouses, storefronts and loading docks across Denver, Lakewood and the metro. We work on every brand and every operator type, carry stock on the truck for most repairs, dispatch 24/7 when a door cannot wait and can send a certificate of insurance, usually within 24 hours. See commercial spring repair, commercial maintenance plans and commercial garage door repair, call (720) 421-6489, or contact us to have your door looked at.

Sources

• DASMA, ANSI/DASMA 109: Standard Method for Testing Garage Doors, Determination of Life Cycling Performance
• DASMA, TDS 190: Factors Affecting Spring Cycle Life
• DASMA, TDS 270: Recommended Rolling Door Maintenance Practices for Building Maintenance Supervisors
• DASMA, TDS 176: Adding Weight to a Garage Door Assembly