The first sheets of self-cleaning glass started whizzing off the production line in 2001, with Pilkington credited with their development– miracle glass that could keep itself clean, perfect for all those hard-to-reach places like on multistorey buildings and glazed canopies. Surely that would be the end of high-rise window cleaners… But no, just like many things in life, it was not that simple… phew! But it did give us a nervous moment!

Why window cleaners need not worry

There are two fundamental reasons why it didn’t worry us for long: 1) self-cleaning glass is expensive, so until they figure out how to bring it in line with pricing expectations, use of it will be limited, and 2) it does need to be cleaned because it still gets dirty, just a little less often than ordinary glass.

How does self-cleaning glass work?

Self-cleaning glass is just ordinary glass treated with a special coating, a film that changes the way the surface reacts to rain and dirt. It stays clean in two stages. The first is a chemical reaction (photocatalysis) that helps to break down dirt that finds its way onto the window and the second is the flow action of rain on the surface, which encourages liquids to flow as a sheet rather than as droplets, to wash dirt away (hydrophilicity).

Why does self-cleaning glass not always work?

So far, so miraculous. However, the cleanliness of your self-cleaning windows relies on outside factors for it to work properly. It requires direct sunlight for the chemical reaction to start to break down the dirt and, of course, it needs rain to wash the dirt residue away. But these conditions are not always guaranteed. If self-cleaning glass has been installed in a shaded location, where the shadow of other buildings limits the sunlight it gets on a regular or seasonal basis, then there will be no chemical reaction to break down the dirt. And, during long, hot summers or cold, dry winters there may be very little rainfall to wash the dirt away.

Cleaning self-clean windows

Due to the coating that gives the glass its self-cleaning characteristic it’s vitally important that it’s cleaned carefully, without any abrasive equipment or chemicals. Luckily we, and many other high-rise window cleaners, only ever use warm, deionised water on self-cleaning windows – pure water, free from chemicals and minerals that could damage, stain or streak windows. And, whether we’re using our telescopic water-fed pole or abseiling down the side of a building we are always careful not to damage the glass we’re cleaning.

If the windows or the exterior of your building are in need of a clean, then contact London Window Cleaners today, the high-rise window cleaning specialists, on 020 3954 2900.


Book a free site assessment today

Contact us for a free assessment for hard to reach windows, high rise windows and any other commercial work.

Call:07983 444 210

Email: [email protected]

Leading London to a cleaner future

London Window Cleaners are proud to receive ‘Go Ultra Low Company’ status. The initiative recognises businesses that are embracing electric vehicles (EVs) as part of a new scheme run by government and automotive industry campaign, Go Ultra Low.

Read more