Lumon's FAQ

Frequently Asked Questions about Lumon glass curtains.

Learn more about our products and processes by browsing these frequently asked questions about Lumon retractable glass curtains. 

Don't see the answer to your question here, one of our experts would be happy to help. Contact us here

Does the glass curtains pass UV rays?

Yes. Some of them. Clear tempered glass emits about half of the UV radiation (exactly 53%).

Can I get tanned through the glass curtains?

Yes. A bit. Tempered glass passes through some of the UV rays of the sun, so it's possible to sunbathe when the glasses are closed!

What do I do if I can not open the glass curtains?

The Lumon frameless glass curtains system for balconies and terraces is very functional and easy to use. If you do not manage to open your glasses, it is probably because:

1. there's no gap between the first (openable) and the second glass panel. Move the second panel smoothly a few millimetres, towards the opposite direction. 

2. Check that the children lock is un-locked

If you can't open the following panels (second, third…) it's probably because they are not totally inside the hinges or the openings in the profiles. If you can't open them, it's for your own security. If the glass panel is not in the right position, it will be impossible to open it.

You can find the opening instructions in pdf format here 
or discover how to use Lumon glass curtains

If the problem persists, do not hesitate to contact us here.

How to ventilate the glazed balcony or terrace?

Gaps 1-3 mm wide between the glass panels are usually sufficient to ventilate the balcony or terrace. If you want even more efficient ventilation, you can open the first panel into the ventilation position. NOTE! The balcony should not be sealed too much. Properly executed ventilation ensures the drying of the structures and keeping them in good condition. If you want to reduce this gap, order transparent PVC seals. In this case, please contact your nearest office. NOTE! Do not leave children or pets on the balcony without supervision, with the glazing in the ventilation position. Due to the risk of falling, the glass curtains are child and pet safe only when fully enclosed.

Are the glass curtains sealed?

Lumon's glass curtains protect the balcony from wind and storm. The Lumon glass curtains are not totally, airtight, sealed or weatherproof. The Lumon system is designed to protect balconies and terraces from lousy weather, but they are not completely sealed (nor are any glass curtain systems on the market), as the terrace also needs ventilation. This is undoubtedly one of the many advantages of this type of frameless systems, which allows you to open your balcony or terrace in summertime, and close it to continue enjoying the space when it gets colder. Due to this, in a period of heavy rains, you may find, in some cases, some water dropping in, although it should not be too much. If it is too much, please contact us here.

Is a Lumon glass curtain a four-season room?

No. Lumon glass curtains are better understood as three-season rooms rather than four-season glass curtains. Unlike a four-season sunroom, which is typically just a regular insulated room with standard double-paned windows, our glass curtains can slide open and retract fully for maximum flexibility.

A Lumon glass curtain is not intended to be a thermal space like indoor rooms but rather a protected outdoor space that enhances the comfort and usability of your patio while maintaining that essential outdoor flavour. 

Can I use the Lumon glass curtains in winter?

Yes. In Spain it's possible.

In a milder climate like in most parts of Spain, homeowners find that they can enjoy their Lumon glass curtains all year round. On the Mediterranean coast, you definitely use your balcony or terrace all year, every day.

Colder climates like northern Europe, Canada or high in the mountains have a shorter balcony or terrace season, but depending on the orientation of the glass curtains, you might still find that you can use it on sunny days in the winter.

See pics of Spanish balconies and terraces here

Visit our Gallery

Can I use the glass curtains as the exterior wall of my home?

Unfortunately not. Our glazing systems were not designed for that purpose. Our Glass curtains are single glazed, tempered panels with 1-3mm gaps between the glass panels to allow for adequate ventilation of your outdoor living space. They are not thermally rated to act as an interior-exterior barrier.

Can I use your glass curtains as an interior wall inside my home?

Yes, we have made many interior applications.

Is there a seal to cover the joints and gaps between the glasses?

Yes, as you can see above, the glass curtains are not 100% water- or airtight, as they need ventilation. That is why between glass panels, there is a gap between 1 and 3 mm. To minimize the wind or rain entering through those necessary openings, we have designed transparent PVC sealings that cover the gap between the glass panels. These sealings will allow you to enjoy your balcony or terrace even more.

If you already have your glass curtains installed, you can contact us so we can prepare them for you. You just have to pick them up at your nearest sales office. Contact us here.

What is happening if my glass curtains make noise?

Lumon glass curtains react to temperature changes, as do all aluminium and glass products. Therefore, if your glass curtains are exposed to sudden temperature changes, due to the dilatation of the aluminium profiles, it may make some noise. We at Lumon have taken this into account in the design of the system and the fixings. It's normal, and it does not affect the safety of the product or the users.

However, if you think the noise is too loud, get in touch with us here

Is it normal for the glasses to bend? Is the bending of glass curtains dangerous?

Lumon glass curtains are designed to withstand weather conditions, wind-loads and hard impacts, so we design them to resist everyday uses and produce the glasses in different thicknesses according to different places and conditions.

Tempered glass may bend slightly. In normal mode, the allowed deflection is 3 mm / m. Thanks to the resistance of tempered glass, it's more resistant to impacts than normal glass. On very windy days, the glass sheets can bend a little more. That's totally normal.

If you consider that your glass curtain has a superior bending and believe that this is not appropriate, or does not work correctly, you can contact us here.

Find more information on how a Lumon glass curtain works

What maintenance does my glass curtain need?

The only maintenance required for the Lumon glass curtain enclosures is: 
Basic cleaning of the glasses, aluminium profiles and the plastic parts. 
You should lubricate the plastic parts and profiles with silicone spray two or three times a year so that they work perfectly for much longer.

Can any silicone spray be used to lubricate the wheels, plastic parts and profiles?

Standard silicone sprays and oils can be used for lubrication. First, we recommend cleaning the profiles and parts and lubricating the system once or twice a year to make the glasses move smoothly. The silicone should be sprayed in a moderate way. Do not use other lubricants or greases such as petroleum jelly, Vaseline or oils. They often attract dirt, which can damage the system's wheelsets. If the glasses do not move smoothly for any reason, please contact our Service Center.

Where can you buy the silicone spray? 
Get in touch with our closest office or with the Customer Service department and we will provide it to you, we even send it to you so you can continue enjoying your terrace.

How do I clean my glass curtains? 

The cleaning of the Lumon glass curtains is effortless and safe. 
See our video: How do I clean my glass curtains?

More information on how to use and maintain the Lumon glass curtains

Can I use a pressure washer to clean the glass curtains?

We do not recommend the use of a pressure washer on your glass curtains, as it can damage the rubber seals.

Can patterns, lines or characters appear on the glass surface?

In some glass manufacturing processes, such as tempering, the glass can produce patterns that appear when the glass is frosted, tarnished or steamy. Frostbite is a normal, natural phenomenon. The same phenomenon can occur in car windows. Traces or patterns may appear standing 2 meters away under normal light conditions.

Can I lock my glass curtains?

Yes, every type of glass curtains can be equipped with a locking mechanism. 

What are Lumon glass curtains made of?

Our frameless sliding and folding glass curtains are made of glass that has been tempered for strength and durability, which is then mounted on aluminium profiles and tracks. Tempered glass is 4-6 times stronger than annealed glass, and if the glass happens to break (which is extremely rare), it will break safely into small rounded pieces. It undergoes numerous product tests to ensure its quality and can withstand winds of 300 km/h.

What is the guarantee for Lumon glass curtains?

Lumon Cristales España (Lumon Spain) offers on its products, in addition to the Spanish legal guarantee, a five-year guarantee throughout Spain from the day of installation. Additional warranties apply within certain product ranges – ask your local design consultant for more information.

See here the terms and conditions of our warranty

How much does a Lumon glass curtain cost?

The price of the glass curtain system depends entirely on the balcony or terrace, including its size and structural requirements as well as the installation method. Often, glass curtains are considered "only glasses", even though these are unique custom made products designed to meet the requirements, safety and needs of modern housing standards.
Read more about Lumon glass curtain price

Lumon financing options?

Yes, we have several different financing options available! 
Get in touch with your local consultant for more details.

Can you get glass curtains on the top floor of an apartment building, a penthouse?

You can also buy glass curtains for the top floor of the apartment building. If the balcony has no roof, we can install a glass roof on the balcony. You might want to ask a Lumon expert to visit the site where you can plan the glass curtains together and get a quote for the purchase!
Ask our experts for a design visit.

Ask for a free estimate

Can you get glass curtains on the lower floor of an apartment building?

Yes. We have designed glass curtains for the lower balconies of the apartment building on the ground floor. In this case, the best first step is to ask a Lumon expert to visit the site, where you can plan the glazing together and get an offer for the purchase!

Can I get sun-shades or blinds for my glass curtains?

We recommend getting sun blinds that bring both privacy and protect from direct sunlight. The easiest way is to get your sun blinds is buying them together with the glazing, so you can get them installed the same day. Later, the curtains can, of course, be purchased and the installation itself is not complicated. Learn more about our sun shades and blinds

Do I need a permit for glass curtains? 

Requirements vary in different municipalities, so we encourage you to ask your local design consultant about permits. If one is required, our team will work closely with you throughout this process. Every structure that we build is engineered and complies with local building codes.

Can you build the patio cover or glass curtains on my existing terrace, deck or patio?

The majority of spaces will accommodate a Lumon system. We work closely with you to find the best solution for you and your home, whether that means using an existing space or starting with a fresh canvas.

Who does your installations? Can I install it myself? 

In order to ensure quality and warranty at every stage of the process, we (or our official resellers) take care of everything from manufacturing all the way through to installation. Our professional, full-time installation crews will build your project. Unfortunately, we do not offer DIY kits.

How long is the process from ordering to installation? 

It generally takes 6-8 weeks for a patio cover or glass curtains to be manufactured once you have confirmed the final details and measurements with your design consultant. However, the length of the process may vary due to seasonal production volumes and other factors specific to your project. Your design consultant will discuss all of this with you in advance.

Where are your products manufactured? 

All our glass curtains are made in our state-of-an-art production facilities in Finland.
Always with the Scandinavian design, Scandinavian safety and Scandinavian functionality in mind.
We were the first company in Europe to get the CE-marking for its balcony glazing systems. As a matter of fact. We set the standard. As a Scandinavian company, safety and security is not an option. It's a standard. All of our solutions are analyzed and tested. We do not improvise or apply homemade inventions.

Learn more about the Lumon Group and our Corporate responsibility including Energy Savings and our Carbon footprint


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