How to fix a roller shutter: the 7 most common faults and their fixes

What you need

• PZ2 Phillips and flat screwdrivers
• Tape measure and torch
• Needle-nose pliers
• 3-step ladder
• Vacuum cleaner or brush
• Silicone spray (Wolfpack or WD-40 Specialist Silicone, 5-8 euros)
• 14 or 22 mm shutter strap or 4.5 or 6 mm cord (Gaviota, Micel, 3-9 euros)
• Strap or cord winder, flush or surface-mounted (Gaviota, Pujol, 8-14 euros)
• Set of 2 or 3 shutter hanger straps (Gaviota, 3-5 euros)
• Loose PVC or aluminium slats of the same size (39, 45 or 50 mm, 2-6 euros per metre at Leroy Merlin or Bricodepot)
• Shutter stops and slat end caps (1-3 euros)

Step by step

1. 1

   Lower the shutter as far as it will go

   Do not force it. If it stops at half height, leave it there. If the strap is broken, push the slats down from the top by hand so the curtain drops under its own weight.

2. 2

   Open the inspection cover on the box

   Remove the screws or unclip the front cover of the box, just above the window. Vacuum out the sand and dust. With the torch, look at the axle, the pulley, the hanger straps and the top edge of the curtain.

3. 3

   Check the strap and the pulley

   If the strap is broken or frayed, replace it following our strap guide. If it is intact but slack, the fault is the winder. If the pulley is cracked or the axle moves to one side, note the axle size (octagonal, 40 or 60 mm) to order the part.

4. 4

   Check the hanger straps and the first slat

   The hanger straps are the small plates that join the axle to the top slat. If one is broken or bent, the curtain hangs crooked. They are replaced by unhooking them from the axle and the slat; they come in sets of 2 or 3 and cost under 5 euros.

5. 5

   Look at the guides and the slats

   With the shutter at half height, shine the torch into the side guides. A twisted slat or an end cap that has come out blocks the curtain. Push the slat back into place from inside the box and refit the cap. If a slat is broken, take it out through the box and slide in a new one of the same size.

6. 6

   Clean and lubricate with silicone

   Vacuum the guides, wipe with a damp cloth and apply a short squirt of silicone spray in each guide. No oil or grease.

7. 7

   Test before closing

   Run the shutter up and down three times with the box open. It should go up straight, without jerking, and the strap should retract on its own. If all is well, close the cover without overtightening the screws.

How to fix a roller shutter by symptom: diagnosis in 10 minutes

Before buying anything, lower the shutter as far as it will go and open the inspection cover on the box. What you see inside almost always settles the diagnosis. On strap shutters, check whether the strap is still wound on the pulley and whether the axle turns freely; on motorised shutters, find the motor cable and check that the axle tube has not shifted to one side.

Fault 1, broken strap or cord: the strap hangs from the winder or has disappeared into the box. It is the most common and the cheapest to fix; the step by step is in how to replace a roller shutter strap. Fault 2, worn-out winder spring: the shutter goes up, but the strap does not retract and hangs slack on the wall. Replace the winder with a new one of the same size, 8-12 euros and 15 minutes.

Fault 3, jammed shutter: it will not go up or down, or does so in jerks. Causes range from a slat twisted in the guide to a broken pulley or sand in the guides; we go into detail in my roller shutter will not go up. Fault 4, dropped shutter: the slats have come out of the guide on one side and the curtain hangs crooked. Almost always because the straps joining the axle to the first slat have broken, or because the stops are missing; see roller shutter dropped or off its track.

• Fault 5, broken or cracked slats: replaced one by one from the box, without taking the curtain down, with slats of the same size (PVC or aluminium).
• Fault 6, shutter that drops on its own: the brake on the winder is worn or the spring has no tension; on cord shutters, the cleat or the knot.
• Fault 7, motor not responding: remote batteries, limit switch out of adjustment, thermal cut-out after continuous use, or a dead capacitor.

Common mistakes when fixing roller shutters

Mistake number one is pulling harder. If the shutter will not go up and you give it a yank, the strap snaps, the slat that was twisted breaks and the repair goes from 50 to 120 euros. When a shutter sticks, you open the box and look, you never force it.

The second is buying parts without measuring. 14 mm straps on shutters that take 22 mm, 39 mm slats where 50 mm ones go, surface-mounted winders where the recess is for a flush-fitting one. Measure with a tape and take the old part to the ferretería (hardware shop) or Leroy Merlin. And the third is lubricating with grease or cooking oil: on the coast it attracts sand and salt and within weeks forms a paste that scratches the slats and jams the guides. If anything is needed, silicone spray, and not much.

On motorised shutters we see one specific mistake: taking the motor out thinking it has burnt out when only the thermal cut-out has tripped. Tubular motors stop after 4-6 minutes of continuous use and start working again on their own after 10-20 minutes. If you have just run the shutter up and down several times, wait before touching anything.

When to call a professional and what it costs

It makes sense to call when the fault involves the axle, the pulleys, the bearings or the motor, when the curtain weighs more than 25 kilos (foam-filled aluminium shutters over 2.5 metres), or when the box is external and the work has to be done from the facade. Also when it is a holiday home and the shutter has been stuck for months: there are usually several faults at once.

Our fixed prices for roller shutter repair, including call-out and materials: strap replacement 35-60 euros, cord and winder 40-70 euros, dropped or jammed shutter 50-120 euros, replacing 1-3 slats 50-100 euros, axle or pulley replacement 80-150 euros and motorisation with the motor included 180-320 euros. The full table is in how much it costs to repair a roller shutter and the service in roller shutter repair.

Send a photo of the open box by WhatsApp and we give you the price before setting off. We arrive in 20-45 minutes in Valencia, Alicante, Torrevieja and Benidorm; we have local pages for Valencia, Alicante, Torrevieja and Benidorm.

Maintenance on the coast: sand, salt and sun

Roller shutters in Torrevieja, Benidorm, Dénia or the Malvarrosa work in the worst possible environment: fine sand that gets into the guides, salt that corrodes galvanised steel axles and pulleys, and sun that dries out straps and makes PVC brittle. A shutter repair on the seafront comes round again every 3-5 years if no maintenance is done.

Three things that extend its life: vacuum the guides and the bottom of the box every spring, wash aluminium slats with fresh water and neutral soap (never with ammonia cleaners, which attack the lacquer) and check that the end caps on the slats are in place. In homes closed up for the winter, leave the shutters fully down: that way the curtain is not at half height with the strap exposed and the slats do not bang in the easterly wind.

When it is better to motorise than to repair

If the shutter is foam-filled aluminium, more than 2 metres wide and you have already replaced the strap twice, the problem is the weight: no standard strap or winder copes well with 30 kilos. Motorising it with a 20-30 Nm tubular motor costs 180-320 euros with the motor included, takes 2-3 hours with no building work (it only needs a nearby socket) and puts an end to straps for good. It is the option we recommend most for living rooms in holiday homes and for older people.