When a garage door slams down unexpectedly, it often means something is wrong with the spring tension. Springs control the force used to lift and lower the door. If that tension is off, even slightly, the door won’t move the way it should. It may shut too quickly, jerk during closing, or feel heavier than normal. We often get calls about loud noises or doors that crash down with a bang. That kind of movement isn’t just annoying—it can be dangerous. The faster a door drops, the higher the risk of property damage or injury. In this post, we’ll explain how spring tension works, what signs to look for, and how the issue develops. We’ll also go over how proper balance keeps everything working safely.

Understanding What Spring Tension Does

Spring tension keeps your garage door balanced. That is to say, it makes sure the weight of the door is evenly supported. When springs have the correct tension, the door lifts and lowers smoothly. If the tension is too tight, the door might shoot up on its own. However, if the tension is too loose, it becomes heavy and slams when closing.

Torsion springs, usually mounted above the door, twist to build energy. Extension springs stretch to create tension. In both cases, their job is to carry the weight of the door and control movement. When tension is off, the opener has to work harder. As a result, the system strains more and wears out faster. We often see early motor burnout in openers when spring issues are ignored.

The role of tension is crucial. Without the right settings, the entire door can become unstable. If you’ve noticed fast, jerky movements or slamming sounds, it’s time to look closely at the springs. You can learn more about proper setup by reviewing the general info on garage door service in Ottawa.

Signs Your Spring Tension Is Too Low

Most doors are designed to close gently. But when tension is too low, the door loses resistance. That means it falls too quickly when closing. You might hear a loud bang or feel a strong vibration as it lands. That isn’t just noisy. It’s unsafe. It puts pressure on panels, tracks, and other parts.

One clear sign is if your door feels extremely heavy when lifted manually. That often means the springs are no longer helping as they should. Another clue is if the opener reverses after trying to close the door. Some openers have a safety response that stops movement if it senses too much force.

You may also notice a cable loose or slack on one side. That usually happens when one spring does more work than the other. The imbalance causes the door to twist, tilt, or jam halfway. A hard slam is just the most visible symptom. Internal damage can build up quietly behind the scenes.

Once the tension becomes that far off, minor adjustments won’t fix the problem. A professional should check the full system. To get started, we suggest visiting the page on garage door service experts in Ottawa for further steps.

Risks That Come With a Slamming Garage Door

Doors that slam shut wear out parts faster. The force from each drop damages rollers, hinges, and brackets. That added stress bends tracks out of shape and shortens the life of the opener. Worse, it creates a safety hazard. Pets and kids are especially at risk near a door that shuts too quickly.

If you park close to the door, a sudden slam could leave a dent in your vehicle. Likewise, tools and items stored nearby may get knocked over or damaged. We’ve seen cases where panels split or frames crack after just a few hard closings.

There’s also the issue of alignment. A door that drops with too much speed may no longer sit properly at the bottom. That allows cold air, water, or pests to sneak in. Once the seal is uneven, weather exposure begins to affect the garage interior. Drafts and dampness cause other issues over time.

For this reason, spring tension isn’t just a comfort feature. It’s critical for safety and structural care. If you’re dealing with this problem, don’t wait until more things break. Use our garage door repair contact form and we’ll help arrange a reliable inspection.

What Causes Spring Tension to Shift

Several things can lead to incorrect spring tension. Sometimes the springs were never calibrated correctly when installed. Other times, they simply weaken over the years. Spring metal loses its shape after many cycles. That is to say, tension slowly fades with use. You may not notice until movement becomes extreme.

Temperature changes also play a role. Cold weather causes springs to contract. During an Ottawa winter, we often see doors start to misbehave due to shrinking tension. In contrast, summer heat might soften the spring response. These small seasonal changes build up, especially if maintenance hasn’t been done in years.

Another reason is accidental adjustment. Some homeowners try to adjust spring screws without proper tools. Even a small turn can throw off balance. We’ve seen cases where one spring gets tightened more than the other. That uneven pull throws the entire system out of sync.

In short, time, weather, and unplanned tweaks all affect spring tension. Even if the door still works, signs like slamming mean the balance is off. Regular maintenance prevents these issues before they grow worse.

Why Garage Door Balance Matters

Balance keeps everything running without strain. A well-balanced door can be lifted with one hand. That’s how we check the spring tension. If the door feels uneven or slams shut when released halfway, the springs are not doing their job.

Balance is not only about convenience. When it’s right, the opener doesn’t have to push or pull with too much force. That keeps gears from wearing down and motors from overheating. It also prevents the cable system from jerking or snapping.

Think of balance like a seesaw. Springs on both sides must carry equal weight. If one is too loose or tight, the load shifts. That uneven pressure leads to wobbly movement and loud slams. If left unchecked, the door may fall out of track or become stuck entirely.

We always stress the importance of testing door weight and movement every few months. A quick lift test tells us a lot. If your door feels off, slams, or needs a full arm workout to move, let’s check the system.

Steps You Can Take Before Calling

Some basic checks can help narrow down the issue. First, close the garage door and disconnect the opener using the manual release. Try lifting the door halfway by hand. If it drops quickly or pulls back up, the springs need attention.

Next, listen during operation. Scraping, thudding, or banging sounds are warning signs. Inspect the cables along the sides. If they seem uneven or twisted, there could be tension imbalance. Also, look at the spring itself. Any signs of gaps or elongation mean it’s wearing out.

Never try to adjust a spring without training. These parts are under a lot of force and can snap. What you can do is reduce use until it’s fixed. Avoid letting the door close on its own. Lower it slowly and gently by hand if needed.

Keeping the area around your garage door clear is helpful too. That way, nothing gets damaged during a rough close. If the problem seems worse in cold months, note the patterns. Temperature shifts may be part of the cause.

FAQ

What causes a garage door to slam shut suddenly?
Incorrect spring tension is the most common reason. It causes the door to lose balance and drop too fast.

Can I adjust garage door springs myself?
No. Springs hold high tension and can cause injury. Always let a trained technician handle adjustments or replacements.

Why does my garage door feel heavier than usual?
That often means the springs are too loose or broken. The opener alone cannot support the full weight.

Is a slamming door dangerous for kids or pets?
Yes. A fast-closing door can cause serious harm. Keep children and animals away until repairs are made.

How often should garage door springs be checked?
Every year is ideal, especially in areas with cold winters. Small tune-ups prevent major problems later.

Ready to schedule a spring tension check?
Use our contact form to book garage door service in Ottawa and we’ll help restore safe and smooth movement.