There are some, but probably not many of us that actually like cleaning windows. The feeling of cold wet and soapy hands, water dribbling down your arms making your sleeves wet is not one of my favourite hobbies, and that’s not even starting on the wet trouser legs from carrying buckets that slop water everywhere! However if you are one of the few that like to clean your windows then this new invention may not make you too happy.
Back in 2001 a new invention was discovered that allowed window manufacturing companies to add a special coating to the glazing, made from titanium dioxide. This coating remarkably uses properties within, namely photocatalysis and hydrophilicity, which break down the dirt on the window using the weather to help. The photocatalysis element causes the coating to chemically break down any dirt on the window and the hydrophilicity reduces contact angles to very low values making the rain gather as a thin layer rather than droplets. This layer then washes the dirt away. You can find out more by following this link: https://www.pilkington.com/en-gb/uk/householders/types-of-glass/self-cleaning-glass/how-does-it-work
So self-cleaning windows can be particularly advantageous for windows that are placed in precarious positions or in high places that are difficult to reach and of course large commercial buildings where glazing companies glaze numerous floors with giant panes of glass which can only ever be cleaned with scaffolding and harnesses. The coating is also meant to last for the life of the windows which could be a great solution for these types of windows (but be careful not to scratch or damage the coating with hard or abrasive materials as this could affect the windows performance).
However there could also be some drawbacks and these are left open for discussion and opinion. Self-cleaning windows do come with an extra cost, quite obvious really as the panes of glasses are specially coated. The other factor to consider is that the coating relies on the sun and the rain to work. The coating itself only needs a small amount of ultraviolet light to work so this can still be fine on cloudy days, but the titanium dioxide takes 12-48 hours to work properly.
You may also notice when your windows are first installed that they don’t appear to work, but be patient as the coating does take time to activate which can be anything from one to two weeks depending on the time of year when you have them installed i.e. longer in the winter shorter in the summer and of course you need to factor in the need for it to rain which shouldn’t cause to many issues here in the UK! Of course if you find that your windows are looking a little bit less than sparkly installing solid shutters will help mask the problem until such time that your windows are gleaming once again!
Also be aware that photocatalysis only breaks down organic dirt so anything like salt from sea spray or exterior paint will not be cleaned away seamlessly, the good old soap and water method will have to be reengaged to remove these things.
And in answer to our very first question, how about self-cleaning buildings? https://www.independent.co.uk/news/science/three-mile-high-skyscraper-design-coated-self-cleaning-material-eats-smog-a7522491.html