Behind buying a home or a new car, getting new double-glazing installed in your home is one of the most expensive purchases you’ll ever make in your life.

And it’s no surprise that, because there’s a real price tag involved in having it installed, the best prepared and most knowledgeable homeowners who have done their research come away with the set-up they want at the very best price.

The type of glass you choose for your window panes will make a difference to both price, performance, and how long they last you. There are eight main types of glass for sale in the UK and, in this one, we look at self-cleaning glass.

Self-cleaning glass – just how is that possible? Read on.


Introduction to self-cleaning glass

Self-cleaning glass does exactly what it says on the tin. It’s a double-glazing system that cleans dust and other marks from the window.

It does this with something called titanium dioxide. You already come into contact with this in your daily life as it’s contained in white paint and toothpaste. That doesn’t mean that, at the factory, your window pane is smeared with white paint or toothpaste however!

The titanium dioxide is put on in a very very thin layer so that it’s transparent. The layer is so thin that in only affects the amount of light that passes through your window panes by 5%.


Self-cleaning glass captures the dirt

The titanium dioxide does two things. When the sun’s UV rays hit the titanium dioxide, the titanium dioxide’s electrons are stimulated. It’s this stimulation that grabs the water molecules from the air and the reaction between water and titanium dioxide then creates something new called hydroxyl radicals.

The hydroxyl radicals then attack anything that’s organic that’s on the surface on your window pane, slicing them up so they become much smaller pieces. That means that, when the rain comes, it’s much easier to wash the dirt away because they’re not so big and heavy that the raindrops can’t absorb them.


Then self-cleaning glass washes it away, even if there’s no rain

But what if it doesn’t rain? The titanium dioxide then does its second thing.

When rain hits normal window panes, the water tends to gather together in beads. When titanium oxide is coated on the panes, it has the opposite effect. The water actually spreads out evenly all across the glass in a very even layer. It does this all the time as there’s always moisture in the air.

Because your window is vertical, this narrow layer of water is always being pushed downwards by gravity. As it moves down, it sweeps up the bits of dirt and grime that have already been chopped into smaller pieces by the hydroxyl radicals.

PS – You still have to clean the inside of your self-cleaning double glazing. This titanium oxide only works on the panes facing the outdoors.


How much does self-cleaning glass cost?

If you’re considering self-cleaning glass for your home, you’ll be looking at a premium of 15-25% more than you’d pay for standard, annealed glass.

Self-cleaning glass also has great insulation and sound-proofing qualities as a result of the processes it has gone through.


If I’m speaking to an installer about self-cleaning glass, what should I ask?

If you live near the coast, the titanium dioxide coating doesn’t get rid of salt coverings. Also, if you’re in an area where there are lots of airborne pollutants that leave lots of stains on your window, self-cleaning glass may actually make no difference – you’ll still need to wash your windows as much as you did before.

When you’ve got an installer around for your quote, ask him or her about self-cleaning glass and whether they think you’ll experience real benefit from choosing it in your personal situation.