Is a shade sail waterproof and winter-proof?
what a sail can do in rain and in winter
A shade sail can be waterproof, but none is winter-proof. Our sails made of Agora and olefin are water-repellent: normal rain beads off, but water gets through in lasting or heavy rain. If you want to sit dry underneath even in the rain, choose the waterproof Cover version. Before winter, every sail is taken down, dried and stored dry. Here you can read which version suits your patio and what no sail can do.
Agora and olefin are water-repellent
Agora Liso withstands a 180 mm water column. Normal rain beads off, but water gets through in lasting or heavy rain. With a slope of 25 to 30 cm per metre, the water runs off instead of standing in the fabric.
The Cover version is waterproof
The PU-coated Cover fabric withstands over 1,500 mm water column and also keeps out heavy rain. It lets no air through and therefore needs a consistent slope.
No sail is winter-proof
Snow load and storms stress the seams and anchoring more than the whole summer. Take it down in autumn, let it dry and store it dry.
Retract rope tension systems in rain
The rope tension shade sail and rope tension awning are pure sun protection, not a storm or rain roof. In rain, strong wind and storms, they are retracted.
Water-repellent or waterproof compared
Water-repellent and waterproof are two different things. The difference is measured as water column according to UNE EN ISO 20811: it tells you what water pressure a fabric withstands. The table shows the versions in which we sew shade sails, and the laminated variant that we deliberately do not use for sails.
| Version | Water | Air and heat | Fabric | For shade sails |
|---|---|---|---|---|
| Agora, water-repellent | 180 mm water column, normal rain beads off, water gets through in lasting or heavy rain | air-permeable, the heat escapes upwards | 100 % solution-dyed acrylic, 260 g/m², UPF 50+ | True |
| Olefin, water-repellent | hydrophobic, the fibre absorbs 0 % moisture | air-permeable, dries quickly | 100 % polypropylene, 260 g/m² | yes, standard for sails made to your drawing |
| Cover, waterproof | Water column over 1,500 mm, also keeps out heavy rain | lets no air through, the heat builds up a little more | PU-coated polyester fabric, 240 g/m² | yes, with a consistent slope |
| Agora IP, laminated | waterproof thanks to a laminated-in membrane | the membrane is delicate and not UV-stable | Acrylic with a membrane on the back | no, for cushions only |
Shade with air underneath
Agora and olefin are water-repellent. Such a sail gives shade, lets air through and survives rain without damage. In lasting or heavy rain, however, it does not stay dry underneath. You can read which fabric suits your spot under shade sail: which material.
You mainly want shade
Under a water-repellent sail, the heat escapes upwards. On hot days you sit more comfortably underneath than under a dense fabric.
You can plan in a slope
Plan for 25 to 30 cm of height difference per metre along the diagonal. Then normal rain runs off. How to do this is covered under tensioning a shade sail.
Agora made of acrylic
Solution-dyed acrylic with lightfastness 7-8 out of 8 and UV protection UPF 50+. The surface has a water-repellent and dirt-repellent finish. More about the fabric under Agora Liso.
Olefin made of polypropylene
The fibre absorbs no moisture and therefore dries quickly, even in an exposed position. For sails made to your drawing, olefin is our standard. More under olefin.
When you should use a waterproof shade sail
A waterproof shade sail is worthwhile if the seating area and furniture should stay dry even in the rain. For that you accept a little more heat under the fabric.
Rain protection over the seating area
The Cover version also keeps out heavy rain. Under the fabric, the seating area and furniture stay dry as long as the water can run off.
A slope is a must
Because Cover lets through neither air nor water, rain collects in the fabric without a consistent slope. Put the lowest corner where the water may drain away.
Load-bearing points
Masonry, concrete and a post in a concrete footing hold the tensile force, a gutter and a trellis do not. You can read which points and fittings come into question under how to fix a shade sail.
Every shape also waterproof
We sew the triangle, square, rectangle and trapezium in Agora, olefin and Cover. The Cover version comes in 5 colours.
Why no laminated fabric
Agora IP is waterproof thanks to a laminated-in membrane. We do not make it for shade sails: the membrane is delicate and not UV-stable. Agora IP is intended for cushions.
What no shade sail can do
The rope tension shade sail and rope tension awning are pure sun protection, not a storm or rain roof. The rope tension shade sail runs on two carrying ropes between or under the rafters, and without a roof above also on facade plates. In rain, strong wind and storms, you retract it, and the gathered sail then lies under cover.
Even a fixed, tensioned sail should be taken down when a storm is forecast, more under shade sail in wind.
A sail tensioned too flat collects water in the fabric. With a water-repellent sail, standing water gets through in time. With a slope of 25 to 30 cm per metre, it runs off.
A shade sail protects against sun during the season and, as the Cover version, against rain. Because it is taken down in winter and in storms, it does not replace a solid roof.
Why a shade sail is not winter-proof
No sail stays up over the winter, not even a waterproof one. The work is manageable if you keep to the order. Cleaning and stain treatment are covered in detail under cleaning a shade sail.
Snow and ice
Snow load and autumn storms stress the seams and anchoring more than the whole summer. Against snow and ice load, only taking it down helps.
When to take it down, when to put it up again
Take it down before the first autumn storm. Hang it up again in spring, as soon as no more night frosts are expected.
Store dry
Clean the sail and let it air-dry for a day. Then store it in a dry, well-ventilated place, not directly on bare concrete. Moisture during storage is the most common cause of mildew in storage.
Rope tension and folding shade sails
These too are taken down and stored in winter. You can send in a folding shade sail over the winter months for refurbishment, for example to renew the shirring tape. We agree the scope and timing with you beforehand.
Seasonal service for nurseries and property managers
Above all for nurseries, property managers and local authorities, we offer a complete service: dismantling and inspection in autumn, dry, insured storage with cleaning over the winter, and refitting in spring with an acceptance report. We calculate the terms for each order.
The right sail for your patio
We sew shade sails to your measurements in Westoverledingen. The waterproof Cover version costs more than the two water-repellent ones. For the fixed sizes, the price is shown on the item, and for made-to-measure orders the configurator calculates it. You will find all further topics in the shade sail guide.
Shade sail water-repellent or waterproof
Triangle, square, rectangle or trapezium, in fixed sizes or made to measure: made-to-measure shade sail.
All the ways to shade
Awning, sail or curtain at a glance: sun protection for the patio.
On the balcony
If you are not allowed to alter the facade: shade sail on the balcony without drilling.
Fabric for sewing yourself
Our outdoor fabrics are also available by the metre.
Frequently Asked Questions
Sources
- Shade sail guide
- Made-to-measure shade sail
- Agora Liso - measured values
- Olefin - measured values
- Cleaning a shade sail
Last reviewed: 22.10.2026 · Reviewer: Germes-Team
Water-repellent or waterproof for your spot?
Send us the distances between your fixing points and a photo. We will tell you which version suits you and how much slope you need.