A broken roller shutter strap is one of the most common repairs, and you can replace it yourself with basic tools.
Strap-operated roller shutters use a woven fabric strap wound around a spring-loaded coiler inside the wall. Over time, the strap frays, stretches, or snaps entirely. When it goes, the shutter will not move.
This guide covers how to replace a broken roller shutter strap from start to finish. We go through measuring, removing the old strap, threading the new one, and adjusting the tension so the shutter operates smoothly.
Before you start: Strap replacement is a DIY-friendly job, but if your shutter is heavy, mounted high, or has a spring coiler under high tension, consider getting a professional. Fix My Shutters handles strap replacements across Sydney. Book a free assessment here.
Understanding the mechanism helps you replace the strap correctly. A roller shutter strap connects the shutter curtain to a spring-loaded coiler mounted inside the wall cavity or on the wall surface.
When you pull the strap, the curtain lowers. When you release it, the spring retracts the strap and raises the curtain.
The strap runs from the coiler, through a guide slot in the wall or window frame, up and over a pulley at the top of the pelmet, and attaches to the barrel. Every part of that path creates friction and wear.
Most straps in Australian homes are 14mm wide, though some older installations use 12mm. Using the wrong width means it will not seat properly in the coiler or guide slot.
Straps do not fail overnight. There are always warning signs before the strap snaps completely. Catching it early means a calm weekend job instead of a shutter stuck half-open on a Monday morning.
If your strap has snapped entirely, you will need to access the pelmet to retrieve the remaining piece from the barrel. This is still a manageable DIY job, it just takes a bit longer.
Everything on this list is available from your local hardware store. The replacement strap itself costs between $8 and $20 depending on length and width.
| Item | Purpose | Notes |
|---|---|---|
| Replacement strap (14mm or 12mm) | The new strap | Measure the old one first. Buy 30cm longer than you think you need. |
| Phillips head screwdriver | Remove pelmet cover and coiler plate | A drill with a screwdriver bit speeds things up |
| Scissors or sharp knife | Cut the strap to length | Clean cuts prevent fraying |
| Tape measure | Measure strap length | Measure from coiler to barrel attachment point |
| Step ladder | Reach the pelmet | Place on level ground and follow Safe Work Australia ladder guidelines |
| Cable tie or clamp | Hold spring tension during swap | Prevents the coiler spring unwinding on you |
| Pliers | Grip staples or stubborn fixings | Needle-nose works best in tight pelmets |
To calculate how much strap you need, multiply your window opening height by 2.2 and add 0.5 metres. A standard window up to 2.4 metres high needs roughly five metres of strap. Always round up and buy an extra half metre rather than ending up short mid-job.
Safety note: The strap coiler contains a wound spring under tension. If you release it without controlling it, the spring can unwind violently. Always clamp or cable-tie the coiler drum before disconnecting the old strap.
This process takes 30 to 60 minutes depending on how accessible your coiler and pelmet are. If you have done it before, you can knock it out in 20 minutes.
Pull the strap to lower the shutter curtain all the way down. This releases the spring tension in the coiler and makes the swap safer. If the strap has already snapped, you will need to open the pelmet and lower the shutter by hand.
The coiler is usually inside a small plastic or metal housing on the interior wall. Remove the screws holding the cover plate. You will see the coiler drum with the strap wound around it.
Use a cable tie or small clamp to lock the coiler drum in place. This stops the spring from unwinding when you detach the old strap. Skip this step at your own risk. If the spring does unwind unexpectedly, do not try to grab it. Let it spin out, then reset the spring tension from scratch.
Start at the top. Thread the new strap over the pulley and attach it to the barrel using the same method as the old one.
If it was stapled, use a new staple. If screwed, reuse the existing screw and plate. Make sure the strap sits centred on the barrel so it feeds straight down to the coiler without rubbing against the pelmet sides.
Feed the strap down through the guide slot in the wall. Remove the cable tie from the coiler, then carefully wind the new strap onto the drum. Make sure it sits flat and does not overlap itself.
Wind the coiler drum a few extra turns to add spring tension. The right amount of tension will retract the strap and raise the shutter smoothly without slamming it up.
Too little tension and the shutter will not fully retract. Too much and it will bang into the pelmet. Start with three or four extra turns and adjust from there. Getting the tension right on the first try is rare, so expect to fine-tune it.
Raise and lower the shutter five or six times. Check that the strap winds evenly on the coiler and the shutter moves smoothly through its full range. Once you are happy, reattach the coiler cover and pelmet cover.
Even with a clean install, new straps can behave unexpectedly in the first few uses. Here are the most common issues and how to fix them.
| Problem | Likely Cause | Fix |
|---|---|---|
| Strap does not retract fully | Not enough spring tension | Remove the coiler cover and add 2-3 extra winds to the drum |
| Shutter slams up into the pelmet | Too much spring tension | Unwind the coiler drum by one or two turns |
| Strap twists or bunches on the coiler | Strap not sitting flat on the drum | Unwind and re-seat the strap so it lays flat across the full width of the drum |
| Shutter stops short of full close | Strap is too short | Measure again using the formula (height x 2.2 + 0.5m) and replace with a longer strap |
| Rough or jerky operation | Guide slot friction or damaged pulley | Sand any rough edges on the guide slot and check the pulley spins freely |
| Squeaking noise during operation | Dry pulley or guide slot | Apply a small amount of silicone lubricant to the pulley and guide slot edges |
| Strap slips off the coiler drum | Wrong strap width or worn drum | Check the strap width matches the coiler. If the drum groove is worn smooth, the coiler needs replacing. |
If the shutter keeps jamming or the strap keeps slipping off the coiler, the problem may be a shutter that will not go up for reasons beyond the strap itself. Worn pulleys, a fatigued spring, or a bent barrel can all cause recurring problems.
Most replacement straps sold in Australia are woven polyester. It is the better choice for almost every installation.
If your existing strap is nylon and keeps stretching, switching to polyester on the replacement is a worthwhile upgrade. The strap should be the same width as the original regardless of material.
Strap replacement is one of the easier roller shutter jobs. But there are situations where calling a professional saves you time and avoids damage.
| Factor | DIY | Professional |
|---|---|---|
| Cost | $8-$20 for the strap | $80-$150 including parts and labour |
| Time | 30-60 minutes | 15-20 minutes |
| Risk | Spring can unwind if not clamped | Handled safely with proper tools |
| Access | Fine if coiler is at ground level | Better for high or awkward installations |
| Diagnosis | You might miss worn pulleys or guides | Full inspection included |
If you are in Parramatta, Penrith, or anywhere across the Sydney metro area, Fix My Shutters can replace your strap and inspect the full mechanism in one visit.
A quality polyester replacement strap should last 10 to 15 years with normal use. Heavy daily cycling, coastal salt air, or a rough guide slot can shorten that to five years or less.
If your strap keeps failing prematurely, the guide slot or pulley might be the real problem. A technician can check for underlying issues that keep eating through straps.
Not on most Australian installations. The strap attaches to the barrel inside the pelmet, so you need to remove the pelmet cover to disconnect the old strap and attach the new one. Some older external-pulley systems from the 1990s are the rare exception, where the strap loops over an exposed pulley outside the pelmet.
A quality polyester strap typically lasts 10 to 15 years with normal use. Factors that shorten its life include daily heavy cycling, salt air in coastal areas, a rough guide slot, and pulling the strap at an angle rather than straight down. Nylon straps tend to stretch and degrade faster, especially in direct sunlight.
Most manual roller shutters in Australian homes use a 14mm wide strap. Some older installations use 12mm. Measure the width of your existing strap before buying a replacement, or check the markings on the coiler housing. Using the wrong width means the strap will not sit properly in the coiler drum or guide slot, and it will wear out faster.
Multiply your window opening height by 2.2, then add 0.5 metres. For a standard 2.4-metre window, that works out to roughly 5.8 metres. Always round up. Buying a strap that is too short means starting the job again, while a strap that is too long just needs trimming.
Expect to pay between $80 and $150 including parts and labour. The strap itself is only $8 to $20, so most of the cost is labour and the callout fee. A professional will also inspect the full mechanism for worn pulleys, a fatigued spring, or barrel damage, which can save you a repeat visit down the track.
If your shutter is in good condition, motor conversions typically start from $600 per opening and reuse your existing curtain and barrel. It makes sense for hard-to-reach shutters or if you want remote control. For most ground-level windows, a new strap is the more practical and affordable option.
The strap is probably the wrong width for your coiler drum, or it was not wound flat during installation. Remove the coiler cover and check that the strap sits evenly across the drum without overlapping. If the coiler itself is worn or cracked, it may need replacing.
Motorised roller shutters do not use straps. They are driven by a tubular motor inside the barrel, controlled by a wall switch or remote. If your motorised shutter is not moving, the issue is with the motor, remote, or power supply, not a strap. See our guide on how to reset a roller shutter motor as a first step.
Not usually. The coiler spring and drum outlast several straps in most cases. Replace the coiler only if the spring has lost tension and will not hold the shutter up after winding, the drum is cracked or warped, or the strap keeps slipping off even when wound correctly. A worn coiler will show the same symptoms no matter how many new straps you fit.
The coiler drum will spin rapidly and the loose spring end can whip around inside the housing. It is unlikely to cause serious injury on a residential shutter, but it can give you a sharp sting and will definitely startle you. The bigger problem is that you then need to re-tension the spring from zero, which adds 15 to 20 minutes to the job. This is why clamping the drum before you start is worth the 30 seconds it takes.
Replacing a roller shutter strap is a practical DIY job that most people can handle in under an hour. Measure your old strap, buy the right width, clamp that spring, and take your time threading the new one.
If the job is more involved than you expected, or your shutter has other issues besides the strap, call Fix My Shutters on 0452 536 233. We have been repairing roller shutters across Sydney for over 15 years, and strap replacements are one of our most common jobs.
Many of the issues covered in this guide can be fixed at home with the right tools and a bit of patience. If the problem is beyond a quick DIY repair, or you would rather have it done properly the first time, we offer professional roller shutter repairs in Sydney. With 15+ years of experience and same-day emergency service, we have fixed every type of roller shutter problem across the city.
Whether you are in Blacktown, Liverpool, Narellan or Macarthur, we can usually have a technician on site within 24 hours. Visit our Sydney roller shutter repair page for full details on the suburbs we service, or get in touch directly for a quote.
Related guides: How to Set Limits on a Roller Shutter · How to Open a Roller Shutter Without Electricity · Signs Your Roller Shutter Spring Needs Replacing
