How Do Self-Cleaning Windows Work?

How Do Self-Cleaning Windows Work?

July 23, 2019

In some cases, windows can be hard to clean, especially ones on the upper levels of your home. Self-cleaning windows might be right for you if you are constantly bothered by water stains on your window glass. They do not require as much maintenance as traditional units. All they need are the sun and rain for the glass to remain crystal clear. 

In this post, your leading replacement window and door provider, Renewal by Andersen® of Eastern NY, explains how self-cleaning windows work.   

Self-Cleaning Glass

Glass is often used in places that are hard to reach and this problem encouraged the development of self-cleaning glass. Renewal by Andersen replacement windows features a very titanium dioxide coating on the surface of the outer pane. This white, powdery component is also found in paint, toothpaste and other kinds of bright white things. 

You may be wondering that if titanium dioxide makes an item white, why is it coated over glass because of course, you want it to be as clear as possible. The coating is extremely thin, around 10 to 15 nanometers deep on glass or 4mm thick. It only reduces about five percent of light that passes through the glass. Self-cleaning glass is created to have anti-reflective, anti-fogging and anti-abrasive properties. 

How It Works

Photocatalyst materials make chemical reactions when the right kind of light hits them. For titanium dioxide, it is ultraviolet (UV) light, blue high-energy light emitted by the sun, which isn’t visible to the naked eye. It has negative effects on the human body and can harm you even when it’s cloudy.

The reaction between UV and titanium dioxide coating of a self-coating glass produces electrons. The water molecules from the air are converted into hydroxyl radicals that create chemical oxidation and reduction reactions on the coating. As a result, the hydroxyl radicals target organic (carbon-based) dirt and breaks them down into smaller pieces that can be easily washed by the rain. This exact component makes our double-hung windows easier to clean and maintain. 

Glass is typically hydrophobic or water-averse. Water that falls onto glass tends to form droplets, which can leave unsightly streaks on the surface. When coated with titanium dioxide, the hydroxyl radicals generated from photocatalysis turn the glass hydrophilic or water-loving. 

Instead of falling in droplets, water molecules spread out evenly across the glass in an even sheet. When the rain splashes over a self-cleaning window, it fans out like a huge cloth. It will leave the glass without streaks or stains when it dries. 

According to studies, superhydrophobic surfaces create microstructures and/or nanostructures that improve the contact angle of water. This makes the droplets quickly roll off as they carry dirt and other particles away.


Self-cleaning windows are appealing and the coating lasts its lifetime. They save you time and money from cleaning and reduces the risk of accidents from climbing up a ladder. These windows are available in different thicknesses and with heat-reflecting inner coatings for increased energy efficiency. 

The coating reduces the number of times you will need to clean your windows. You do not have to worry about dirt buildup on your windows and water spots during rainy days. Your trusted window company, Renewal by Andersen’s glass technology reduces water sorts by up to 99 percent, allowing you to enjoy an uninterrupted view of the outdoors. 

This technology can be used in other things aside from windows, like solar panels and building facades. These are places that are usually harder to access and maintain. Self-cleaning technology has been used for solar thermal panels, which make hot water and photovoltaic solar cells, which generate electricity.

Benefits of Andersen’s Low-E4 Glass

Renewal by Andersen’s Low-E4 glass is ENERGY STAR® certified and suitable for all climates. The special titanium dioxide coating on the glass does not only make cleaning easier, but it also causes rain and condensation to sheet off effortlessly. Aside from that, it increases water’s evaporation rate, which means fewer water stains

We use an argon gas blend to reduce heat and cold transfer through the glass, helping you save on energy. Our window pans are secured with a low-conductivity, stainless steel space. Another great feature of our high-performance glass is noise reduction. With our windows, you’ll have a more peaceful, comfortable and quieter indoor space. 

Ultraviolet light can harm both you and your furniture. All the windows that your leading window contractor produces have 11 microscopic coatings that block a significant amount of UV radiation, while still allowing a lot of visible light. This saves your wood furniture from fading and upholstery from solar damage. 

Each one of our Low-E packages is extremely durable. This makes our windows less vulnerable to damage while shipping and handling compared to other windows. We also attach a protective film on our glass, which makes it ultimately pristine throughout manufacturing and installation. 

Only trust an experienced and reputable window company like Renewal by Andersen of Eastern NY for your home improvement needs. Our windows are designed to improve comfort, increase energy-efficiency and last for a long time. In addition, our windows and patio doors come with some of the most comprehensive warranties in the industry. All you have to do is contact us and schedule a consultation so we can start planning your window replacement. Call us at (866) 479-1700 or fill in our online form to schedule a free in-home estimate. 

Hear From Our Customers

Excellent Installation. Very friendly and professional customer service. Very thorough from the second they started to the cleanup. Explained everything perfectly. Could have not asked for better service.

We had a Great experience with Andersen Windows. From sales through installation. Everyone was super helpful and they did a great job!

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