A zip screen is an outdoor blind system in which a zip strip is welded onto the edges of the fabric and locks into the aluminium rails at the sides. In a classic blind the fabric hangs only from the bottom bar; in a zip system it is fixed into the rail on both edges. That single structural difference completely changes how the system behaves in wind and where it can be used. In this article we look at how a zip screen works, what each fabric is for, and what matters for a correct installation.
At the centre of the system is the zip-and-rail lock. The zip strip, joined to both fabric edges by high-frequency welding, enters the channel inside the side rails and stays mechanically locked there. As the fabric descends the strip travels along the rail; as it retracts, the strip comes back out. That lock keeps the fabric taut at all times, stops it flapping in wind and leaves no gap at the edges. The billowing and the entry of rain and insects at the edges seen in classic blinds disappear in this system.
Wind resistance is a zip screen's clearest advantage. Because the fabric is fixed on both edges, the wind load does not concentrate at one point but spreads along the rail. That gives markedly higher resistance than a classic blind of the same size. Even so, a zip screen is a system with a flexible surface and must be retracted above a certain wind speed. On motorised models we therefore regard the wind sensor not as an optional accessory but as a safety component of the system.
Sun control is determined by the fabric choice. Micro-perforated screen fabrics have a value called the openness factor, expressing the proportion of holes in the fabric surface. Fabrics with a low openness factor block more sun and increase privacy, but make it harder to see out. Fabrics with a high openness factor preserve the view but shade less strongly. Your façade orientation and what you expect from the view determine which way you set that balance.
An important property of screen fabric is that it gives one-way vision. By day, because it is brighter outside than in, you can see out while the inside cannot be made out from outside. When you turn the lights on in the evening that balance reverses; with the inside lit and the outside dark, the direction of vision changes. If evening privacy matters, it is worth knowing from the start that screen fabric alone will not be enough.
Transparent crystal PVC fabric serves an entirely different purpose. It is a clear surface with no perforations; it blocks wind and rain completely while preserving the view almost undisturbed. It is the fabric most often chosen for closing a terrace in winter and for making outdoor areas at cafés and restaurants usable on cold days. Against that, it does not breathe; moisture can build up inside when enclosed, so ventilation must be planned.
Blackout fabric, by contrast, blocks light entirely. It is chosen where full privacy and darkness are needed - a terrace section facing a bedroom, for instance, or outdoor areas where a projector is used. Because the fabric passes no light, it cools the space beneath noticeably. Since it closes the view completely, it is usually used only on the section where it is needed, not across the whole façade.
Insect control is an often-overlooked advantage of the zip screen. Because the fabric locks into the rail on both edges and the bottom bar meets the floor, the edge gap seen in classic blinds does not occur. If the hole size in the screen fabric is small enough, flies and similar insects are kept out. For smaller creatures such as mosquitoes there are zip fabrics with a special insect-mesh weave; these let air through and largely preserve the view while blocking insect entry.
A zip screen should be thought of as the side enclosure of a system, not on its own. When a bioclimatic pergola, rolling roof or glass roof above comes together with zip screens at the sides, the outdoor space becomes a sheltered volume. In summer, screen fabric filters the sun and preserves natural ventilation; in winter, crystal PVC blocks the wind and, with an infrared heater, makes the area usable. Using different fabrics on the same façade by season is also possible.
The difference between motorised and manual is decided by how often you use it. A manual zip screen is economical for infrequent use and narrow sizes. The motorised model provides comfort at larger sizes and in daily use; moreover, wind, rain and sun sensors work only on motorised systems. If you plan to use sensors, the motorised model is essential; it can be run by remote control, wall button or mobile app.
Dimensional limits should also be kept in mind. As width grows, so do the wind load on the fabric and the tendency of the roller to deflect. Very wide openings are therefore solved with several modules rather than a single screen, with an intermediate post between them. On height, cassette size is the deciding factor; because the fabric winds into the cassette above, longer screens need a larger-diameter cassette.
The critical point in installation is fixing the side rails and the cassette to a sound structural element. The rail takes the wind load from the fabric and transfers it to the structure; a rail fixed to a weak point shifts over time and disturbs the grip of the zip lock. Anchoring must go into a reinforced concrete beam, a column, or the pergola's structural profile. It is also important that the rails are exactly aligned on the vertical axis; on a crooked rail the fabric drifts to one side.
Three points stand out in maintenance. When dirty, the fabric is cleaned with warm water and a pH-neutral soap using a soft brush and rinsed with plenty of water; pressure washing and bleach must not be used. Dust and sand collecting in the channel inside the side rails make the zip strip harder to move, so cleaning that part regularly extends system life. Not leaving the fabric retracted while wet for long periods is the most important rule.
The technical items to check when deciding are these: fabric type and openness factor, the weld quality of the zip strip to the fabric, the rail profile section and the depth of the zip channel, cassette diameter, motor brand and lifespan, whether a wind sensor is included, and where the anchoring will go. We suggest asking for these items in writing in the quotation.
In summary, a zip screen is a side enclosure solution that stays taut in wind thanks to its zipper edge lock, filters or fully blocks the sun depending on fabric choice, and keeps insects out because it leaves no edge gap. For the right result, the fabric type should be chosen for the façade orientation, the rails fixed to a sound structural element, and the wind sensor kept active. You can review our zip screen systems and we can determine the right fabric for your space together.
To settle on the right zip screen fabric and dimensions for your terrace, request a free site survey.
Frequently Asked Questions
Because the fabric locks into the rail on both edges, it is markedly more resistant than a classic blind. Even so it is a flexible surface and should retract automatically above a set speed via a wind sensor.
Yes, if blackout fabric is chosen. Screen fabric filters light and crystal PVC is transparent; if darkness is wanted, the fabric type must be chosen for that from the start.
Yes. Because the fabric locks into the rail on both edges, no gap forms. For small creatures such as mosquitoes, zip fabrics with a special insect-mesh weave can be used.
