Self-Cleaning Glass: A Promising Product

The arrival of spring often brings its share of cleaning tasks, such as cleaning windows, for example. Both long and tedious, the process of cleaning window after window can be a moment of pure boredom that is hard to get through, even with good background music playing.

A glimmer of hope timidly appears in the form of a newly marketed technology: self-cleaning glass.

What is Self-Cleaning Glass?

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How Is Self-Cleaning Glass Made?

The manufacturing of self-cleaning glass begins with the creation of float glass. This is actually a flat glass on which a very thin protective layer (a layer of titanium dioxide) is applied. Its production mainly consists of floating the molten glass on the surface of a tin bath before being molded and cooled. A furnace designed to produce this type of glass can produce panes with thicknesses varying between 2 and 19 millimeters.

This technology, once reserved for certain large-scale buildings around the world (think of some office buildings in Brussels, Italy, or even the Louvre pyramid), is gradually becoming available commercially.

How Does Self-Cleaning Glass Work?

Self-cleaning glass operates in two ways. First, through activation by light, where the titanium dioxide layer changes the contact angle between the glass and water droplets. Titanium dioxide acts as a photocatalyst, meaning chemical reactions occur when ultraviolet or UV rays come into contact with the window. When UV light reaches the layer, electrons are generated. These electrons transform water molecules into hydroxyl radicals. These hydroxyl radicals attack dirt, breaking it down into small particles that are washed away by rain.

Secondly, self-cleaning glass is hydrophilic, while normal glass is hydrophobic. When it rains, hydrophilic glass causes water to spread out and form a uniform film instead of remaining as individual droplets. Thus, rainwater can clean the entire pane rather than leaving streaks and marks often seen on standard glass. Titanium dioxide and the hydrophilic properties work together to help self-cleaning windows maintain their clean appearance.

Advantages of Self-Cleaning Glass

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Self-cleaning glass features two main and distinct advantages over traditional glass:

• First, it allows organic matter deposited on the glass to decompose under sunlight thanks to photocatalysis. But what happens on gray, cloudy days? Since most sunlight rays still manage to pass through clouds, the process’s effectiveness is not affected.

• Second, it is hydrophilic. Whereas water usually runs off as droplets on the glass surface, self-cleaning glass causes water landing on it to turn into a film that then slides down. This prevents the dirt marks caused by drying droplets on the surface.

These two characteristics work closely together, which explains their effectiveness. When debris is broken down, all you need is to wait for a rainy day or spray the window so the water film slides down and carries away all debris. Likewise, self-cleaning windows dry faster than conventional windows.

Besides these advantages, self-cleaning glass technology is very helpful for reaching high windows or cleaning buildings with large amounts of glazing. Also, note that frost does not stick to self-cleaning glass surfaces, which is quite practical during the cold season.

Although an indirect advantage, the fact that the glass does not require detergent products is environmentally responsible and, at the same time, reduces the costs related to purchasing cleaning supplies.

Disadvantages of Self-Cleaning Glass

Like every coin has two sides, some disadvantages exist regarding this technology. The first disadvantage concerns the possible incompatibility of new windows with existing frames, which will unfortunately require replacing them and therefore additional expenses.

Secondly, it must be noted that the breakdown of organic compounds absolutely depends on sunlight to work. Therefore, glass panes not exposed to sunlight due to their location will not be able to eliminate debris on their surface.

Next, it should be highlighted that certain waste (such as bird droppings) will require extra help to be removed from the glass surface. In this case, soap will be necessary. However, be careful not to use detergent products containing fatty acids, as these could make the glass surface hydrophobic. It should also be mentioned that self-cleaning windows cannot remove mineral deposits. These can thus contribute to dirtying the window just like traditional glass. Therefore, the window will still require manual cleaning, although much less frequently.

How Much Do Self-Cleaning Glass/Windows Cost? What Is Their Price?

Purchasing self-cleaning glass will require an additional investment of about 10% compared to the price of standard glass.

FAQ

What is the lifespan of self-cleaning glass?

Self-cleaning glass typically lasts 10 to 15 years, depending on the quality of the coating and environmental conditions.

What are the best practices for maintaining self-cleaning glass?

Clean gently with water and a soft cloth when needed. Avoid harsh chemicals or abrasive cleaners to protect the coating.