FAQs answered



We work with a selection of reputable dealers to sell our exclusive canopies, awnings, glass systems, aluminium frames and garden houses. Would you like to meet with a CORNELS dealer in your area? After delving into your requirements and location,  our dealers will provide expert personalised advice. Every project is different and fully customised.

Looking for more inspiration and want to get your bearings first? Please make an appointment to visit our showroom.

That depends entirely on your selection. Almost all high-quality products are fully tailor-made. This means we will start the production of your order after approval of the design and technical drawings. For aluminium window frames and terrace canopies, for example, we now assume a – relatively quick – delivery time of around eight weeks. Our delivery times also set us apart from other suppliers/manufacturers.

Our high-end products for exclusive outdoor spaces are entirely tailored. As a result, customer requirements are met almost every time. In fact; we like to exceed expectations. Our selected dealers have realised many complex projects. With a full focus on the customer’s needs and taking into account the specifications of the location. Our specialists work with our dealers to design products with the ultimate mix of innovative and high-quality technology and aesthetic design. The result? Outdoor solutions that perfectly match the your desired ambience.

We work with a selection of reputable dealers to sell our exclusive products. We will gladly connect you with a dealer in your area.


We look forward to welcoming you to our showroom in Nieuw-Vennep (near Schiphol Airport). The showroom boasts various product arrangements and can be visited by appointment only. One of our advisors will take their time to go through your questions and requirements. We will look at the different options and set-ups and will be happy to advise you.


You are welcome to visit our showroom in Nieuw-Vennep. We work by appointment only. This allows us to devote all our time and attention to your questions and needs.

Together with our selected dealers, we have extensive experience in very diverse project assignments. From an intimate terrace at home to comprehensive business projects. We work on behalf of property developers, architects, contractors, municipalities, housing associations and hospitality operators. Every assignment is unique and together we find the best possible technical solution for the issue at hand. And the ultimate design that best suits the desired ambience. Want to know what CORNELS can do for your project? Get in touch.

This can only be determined once we know what exclusive products we would be building for your outdoor space. All products in our high-end range are custom-made, based on many variables. Such as size, materials, design, operation and the scope of the project. There are many factors that affect the price. Needless to say, ‘personal production’ comes with a personal price tag.

The quote is part of your personal project plan. After you have discussed your requirements with one of our exclusive dealers. Once we have walked you through the many customisation options. We cannot give you a standardised quotation because we only work with high-end, custom-made products.

We can, however, provide a price indication upon request, allowing you to determine whether our high-quality outdoor living products fit your project and budget.

Generally speaking, no municipal permit is needed to install a terrace canopy in The Netherlands. There are specific situations, however, where a permit is required. For example, when installing a canopy in a high-visibility location, such as your front garden. In addition, the percentage of the plot that can be built on permit-free is subject to rules. A terrace canopy with retractable roof is not actually a structure, so it should not count towards your built-up area. This is in contrast to a fully insulated conservatory/garden room, which will probably require a permit. Permit policies may vary from one municipality to the next. Not sure if you should apply for a permit? Your CORNELS dealer in your country and area will be happy to join your thought process and inform you about the possibilities and limitations.


The terrace canopy with louvred roof, the glass roof and the version with folding fabric are all waterproof. Even when it rains, you will be enjoying your exclusive outdoor space without a care in the world. Furthermore, the louvres of a louvred roof from the CORNELS® Elite series are insulated. This reduces condensation and air humidity.

Since the terrace canopy is not fully insulated, some condensation may build up in the room during storms with rain or as a result of large temperature fluctuations. Condensation does not affect the quality or the service life of our products in any way.

Every CORNELS terrace canopy is completely custom-made. Your needs and specific circumstances determine the design prepared by the dealer. This means that each canopy is unique with no second copy in existence. The colour application, design, materials and execution are completely tailored to your project.

A foundation is required for installing terrace canopies with a louvred or retractable roof. The same applies to retractable glass windscreens (executed without a planter). Your specific location determines the type of foundation. Peat soil, for example, requires a firmer foundation than sand. We generally use screw piles, concrete floors or concrete foundations for terrace canopies. We will be happy to tell you more about what foundation your site requires.

Unless otherwise specified, our terrace canopies are made of aluminium. The frame is finished with a low-maintenance, protective powder coating. To keep the terrace canopy in good condition, we recommend cleaning the structure 2 to 3 times a year. Use lukewarm water, a mild detergent and a soft cloth to clean the uprights and beams. Avoid using aggressive detergent and abrasives/scouring pads.

The louvres can also be cleaned with a cloth. Tilting the roof open makes it easier to clean the top of the louvres.

You can clean the inside of a PVC fabric retractable roof with water and a mild detergent.

If your canopy is located in a wooded area, it is recommended to clean the canopy gutter on a regular basis. This prevents clogging of the rainwater drain.

Do you have a terrace canopy with glass systems? We recommend using a suitable detergent combined with lime-free water.

A terrace canopy is a structure made of aluminium (or steel for larger spans). The roof of the canopy features movable louvres (retractable, tilting or both) or a retractable roof made of high-quality PVC fabric. A terrace canopy can be either detached, standing independently in the outdoor area, or attached to the building’s façade.

A conservatory is a fully insulated structure. The profiles are thermally broken to prevent thermal bridges. When installing a conservatory on the façade, the external wall (façade) is usually breached and/or back doors are removed. Creating a conservatory is generally a more intensive operation and demands a larger investment than installing a terrace canopy, garden room or veranda.

A veranda is an extension that is attached to the façade, usually supported on wooden pillars. These can also be made of aluminium. The walls of a veranda are open. The roof is fixed and does not retract or tilt.

If the walls of a terrace canopy are enclosed with glass walls, for example, the result is called a garden room. To make a garden room suitable for all seasons, we can install insulation glass (double glazing). While a conservatory is a fully insulated structure, and remains heated, a garden room can be heated with terrace heating. The indoor climate will cool more quickly than in a conservatory.

The main differences are in the construction of the frame and the type of fabric. A terrace canopy with retractable roof comes in PVC fabric. This blackout or translucent PVC fabric is waterproof. A terrace canopy with a retractable roof is equipped with a gutter and rainwater drainage. A pergola awning features fabric as well, but in this case it is made of water-repellent acrylic. Water-repellent means that the material temporarily keeps the rain out, but in heavy showers and prolonged rain, rainwater does leak through the fabric. A pergola awning is not equipped with a gutter or drain for rainwater.

A terrace canopy with retractable roof made of PVC fabric is much more resistant to strong winds than a pergola awning with acrylic fabric. The acrylic fabric needs to be retracted in the case of strong winds to prevent the retractable roof from being blown apart.

In fact, a terrace canopy with PVC retractable roof can be used in almost all weather conditions. You can create an atmospheric garden room by closing off the side walls,  An exclusive living space for you to enjoy all year round.

The main purpose of a pergola awning is to block out the sun. To create extra shade on the terrace. A terrace canopy with retractable roof offers many advantages in all seasons. In addition to sun protection, the retractable roof also keeps out the rain and the structure is wind-proof. Making your outdoor space a pleasant place to spend time, even during showers and stormy weather. Combined with side walls, a unique garden room can be created.

Would you like to know more about the benefits of a terrace canopy with retractable roof compared to a pergola awning? Read all about it in our blog Benefits of terrace canopies over pergola awnings.

Most louvred roofs from the CORNELS® Elite series are insulated. This benefits the indoor climate and reduces impact noise, for example during rain and hail. We can fit our glass canopies with thermally broken insulated glass as needed. Sealing the walls of a terrace canopy with double or triple glazing creates a cosy living space that can be used in all seasons.

In terms of engineering and insulation values, a terrace canopy is not the same as a conservatory. A terrace canopy is not thermally broken and therefore has a lower insulation value. A conservatory is fully insulated. As a result, the breach of the home, hospitality building or business premises is not accompanied by heat loss.

Unlike a conservatory, an insulated terrace canopy needs an additional heat source in autumn, winter and early spring for the outdoors to be enjoyed in comfort.

You certainly can. To enjoy a comfortable indoor climate in all seasons, an additional heat source can be used when the outside temperature demands it. Such as a heater or a fireplace. Especially if the walls of the terrace canopy are closed off with insulated glass, you can enjoy the benefits of a unique extra living space all year round. From sunrises in early spring to atmospheric winter evenings.


Our high-quality products are highly weather-resistant. However, we advise you to take extra precautions as soon as the weather institutes issue a code orange/red for extreme weather conditions. The most important advice in storms and heavy gusts of wind: open everything or close everything.

So do you have a canopy roof where the side walls, or part of them, are not closed off? Then open the roof as far as possible. Slide open the complete folding roof made of PVC fabric or the retractable louvred roof. Do you only have tiltable louvres? Tilt them to the most open position. This allows the wind to blow freely through the structure.

Is your patio covering fully equipped with lockable walls? Then open everything or close everything. Do you open everything? Then don’t forget to secure your furniture and loose home accessories in advance. Do you have screens? Make sure you retract them too.

Naturally, height-adjustable windbreak screens should be retracted during storms and heavy gusts of wind.

Our louvred roofs are extremely strong and highly resistant to the load of a heavy pack of snow. The roofs have a load-bearing capacity of around 300 kg of snow per m² (depending on the size of the canopy).

Our glass roofs can withstand quite a bit of snow as well.

A terrace canopy with a retractable roof made of PVC fabric can only support a light snow load. If a considerable amount of snow is expected, of 20 centimetres or more, it is recommended to fully open the retractable roof as a precaution.

The most exclusive louvred roof in our collection is the AVIOR from the CORNELS® Elite series. The AVIOR combines both functions in one unique system. The insulated louvres of this roof are both tilting and fully retractable. This gives you the ultimate freedom to let in the desired amount of light, shade and air.

The ALYA system from the CORNELS® Pro series features a slender design with tilting louvres. The ALYA from the CORNELS® Elite series offers a more robust design and unprecedented possibilities in terms of size and execution.

POLLUX from the CORNELS® Elite series is a louvred roof that can be fully opened or closed.

To sell our exclusive canopies, awnings, glass systems and aluminium frames, we work with a selection of renowned dealers in the Benelux.

In addition to unique and high-quality customised products, we offer our dealers an attractive dealer package. CORNELS offers them a lot of professional support; from engineering advice, drawing work and online and offline marketing to the deployment of skilled assembly teams. Not to mention; a beautiful dealer showroom to receive your customers.

Are you interested in joining our exclusive dealer network? Contact us for more information.

The system is perfectly suited for interior applications as well. We regularly install sliding glass walls and folding glass walls in indoor spaces. A segmented layout of office gardens and meeting rooms, for example.

Furthermore, the glass systems are used to divide spacious terrace canopies into enclosed segments, e.g. for hospitality establishments. This creates cosy corners for the reception of private parties. Warming up a space with terrace heating under cold weather circumstances becomes a lot easier when segmented.

The high-quality screens by CORNELS represent a stylish way to block out the sun. The exclusive awning can be used in a variety of ways. For example, with screens in the walls of your terrace canopy. This application brings additional shade and coolness to the terrace while limiting the intrusion of a low winter sun.

In addition, screens are perfectly suited for awnings around homes, offices and public buildings. Not to mention applications in hospitality, such as hotel rooms and restaurant facilities.

In addition to their sun-blocking function, screens provide additional privacy as well. Enjoy an almost unrestricted view of the outdoors, while maintaining limited visibility for those looking in.

This vertical awning completely covers your windows on the outside. Because the screen fabric is attached to the side rail with a zip, a stagnant layer of air is created between the screen and the glazing. Stagnant air has an insulating effect. The insulating layer of air keeps the space cool in summer and warmer in winter. Our screens offer extra privacy as well: your view is virtually unobstructed, while maintaining a limited view for those looking in. Finally, the zip system guarantees that the screens and guide rails make up a wind-proof structure. Aesthetic finish. Sleek design.

Do you want to extend the seasons and experience even more comfort on the terrace? Opt for installing walls in the terrace canopy. You decide whether to keep the terrace canopy (partially) open or close it entirely.

A canopy fitted with closable walls creates a complete garden room. Extra space to enjoy the outdoors in all seasons. Thanks to the generous tailor-made range, almost anything is possible.

Your options:

• Glass sliding walls and sliding doors

• Glass folding walls

• Louvres

• Screens

• Fixed walls such as tongue-and-groove walls

A combination of several high-end products will make for an extra playful effect.

Want to know more about expanding your outdoor living space by installing walls in your terrace canopy? You can find all the information in our terrace canopies, wall systems and garden rooms blog. Or get in touch if you have any questions.

The main benefit of a louvred roof is its ultimate flexibility. Tilting louvres put you in control of light and shade. Shut out the sun or let more light in by silting the louvres. Retractable louvres give you the option to entirely open or close the roof. Meet the ultimate louvred canopy: AVIOR from the CORNELS® Elite series. This system combines tilting and retractable louvres. Best of both…

Furthermore, dirt is less visible on a louvred roof than on a glass canopy. The top of the canopy is easy to clean by tilting the louvres. In summer, a terrace canopy with a louvred roof is cooler than one with a fixed glass roof.

Our louvred canopies all have a stylish design, from slender to robust. All versions are extremely strong and can be used in all weather conditions.

A retractable roof features high-quality fabric. This fabric blocks out the sun, allowing you to enjoy the shade on your terrace. Do you prefer more incident daylight? Go for a terrace canopy with a retractable roof made of translucent fabric.  All the fabrics are waterproof, offering outdoor enjoyment even in rainy conditions. Want to make the most of sunlight? Slide the entire retractable roof open. Do you want a combination of sun and shade? You decide how far you want to open the retractable roof.

Fully customised, the retractable roof is tailored to your needs. Our terrace canopy with retractable roof is available in many versions. This applies to the mounting method (mounted on the façade, floating, integrated or free-standing) as well as the design. A sloping, rounded or flat roof, or modern cubist design; we will be happy to tell you more about the possibilities.

Experience even more light and unlimited space with a glass roof. Both during the day and in the evening hours. And what about the different seasons? Enjoy your outdoor space from the very first early rays of sunshine in spring to the lower sun in autumn and winter. It is easy to create a pleasant climate with a glass terrace canopy. For the winter, however, extra terrace heating is usually recommended. Do you want full control of the temperature even on hot days? Opt for the pleasant benefits of sun protection above or under the glass roof of the terrace canopy. These types of screens are retractable, allowing you to regulate the temperature yourself.