Welcome to our website. Today we'll look at why the box lid of roller shutters can bow, and what to do once it has already happened. Let's start with the most common causes.

Why does the roller shutter box bow?

The roller shutter box houses the shaft onto which the shutter curtain is wound; the curtain itself is made up of slats. The box is fastened at its sides to end caps of the matching size. Those caps, in turn, are attached to the guide rails in which the curtain travels.

The most common causes of a bowed box lid:

• Installing the shutter system out of square. This happens when the surface the shutter is mounted to isn't set true to level. For example, the window opening has distorted geometry. One wall or the sill juts forward by a few centimetres, yet the shutter is set to be mounted onto the opening. Fastening the guide rails to such a surface can leave you with a slight skew, meaning one side sticks out further forward, and the box geometry ends up less than perfect. The same applies to setting the shutter system to level in height, when one side sits higher than the other. This can happen when the customer takes their reference from the floor level, for instance, but the floor is uneven. These skews may not be visible to the naked eye, yet they affect the whole structure. That is exactly why roller shutters for windows or garages need to be set using a spirit level. Better still, entrust the installation of your roller shutter to the professionals at Magnita, who have many years of experience.
• Mounting the box onto an uneven surface. This can occur when the surface above the window has irregularities or dips. The same goes for when one side protrudes forward by a few centimetres. It's a common situation in many Soviet-era buildings, where such details were given little attention. It can also happen after facade renovation work, when plaster was applied by eye. In this case the box will be skewed and its lid may sag. The installation advice here is similar to the previous point: you need to minimise surface variations and use a spirit level when mounting the shutter.
• The box screwed on without tension. This happens when gaps are left between the side caps and the front lid of the box. When fitting the box lid of a shutter, you need to give it maximum tension and try to seat it as tightly as possible.
• Mechanical damage (a bend) to the side cap during transport or shutter assembly.
• Damage to the box lid itself. Something heavy could have been placed on top during transport, bending the shutter's box lid.
• Damage from the end stops when opening. If the customer applies excessive force when raising the shutter and pushes it too hard upward, the stops will strike the lid and it can be damaged.
• As a result of cutting costs. Bowing of the box lid of a roller shutter is possible with an excessive width combined with a thin material. This is done to save money, because the box is expensive.

How do we prevent the box from bowing?

When customers buy large roller shutters for a garage from us, this problem usually doesn't arise with correct installation. But sometimes, as a safeguard, we reinforce the lower edge of the box lid by adding an extra stiffening rib. When choosing roller shutter gates, you can get further information from a manager on this point, namely whether your product will need the structure reinforced, so you can pick the best option.

There are two main methods of reinforcing the box to prevent bowing:

• Creating an additional stiffening rib in production. In this case our specialists take the box lid and, using a sheet bender, form an extra "step" that serves as an additional stiffening rib. Some of our dealers ask us right away to form a reinforced box for them if they know that customers will be buying large roller shutter gates from them. This is usually a small "step", made 10 or 20 mm wide.

• The second option is adding a metal angle bracket. We use an aluminium angle, usually fastened at the bottom of the shutter, which physically restricts access to the lower part of the structure. When reinforcing the box of a roller shutter, the angle is fastened on the inside of the box. This angle is inserted into the lock groove of the box lid along its entire length and riveted evenly all the way along. It doesn't affect the appearance of the finished shutter, yet it adds strength to the whole box and lets you correct the problem if it has already occurred. You can also do this yourself with a minimum of tools.

Both options are shown in the video we've prepared for you. You can watch it on the website or via the link to YouTube.

Is it worth reinforcing the shutter box?

I'd like to draw your attention to the fact that with correct shutter installation this problem shouldn't arise at all. That is precisely why we recommend our customers order the installation service from us or our dealers. Our representatives are located all over the country.

If you've decided to install the shutter yourself to save money, we advise you to set the entire structure using a spirit level.

You can also order the box reinforcement service in advance. It won't cost much, but this way you're guaranteed to get a straight, attractive roller shutter system that will serve for many years.

How to choose roller shutters or get a consultation?

1. Leave a request on the website and our manager will call you back.
2. You can pick ready-made products in our catalogue of finished products
3. You can create your own roller shutter in a custom colour using the roller shutter calculator
4. By phone: (067) 631-38-23, (095) 549-60-62