How to understand double glazing

Some people will remember when double glazing windows were the hot new topic on everyone’s lips, and it was a luxury that not everybody could afford to install within their home.
These days, double glazing comes as standard in almost all newly built properties, highlighting precisely how important it was to home improvements throughout the UK.
Not many youngsters would believe that their grandparents often sat shivering in their home as ice formulated on the inside of their windows, so if the advance in technology was so significant, how come so many of us don’t get what double glazing does?
Fear not!
We’re going to explain double glazing in 5 simple steps:
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1. It has two panes of glass
If you don’t know much about the science behind double glazing, don’t feel bad. For many, the extent of their knowledge is that double glazing has two panes of glass. Okay. Job done. Two panes of glass mean it will probably be twice as warm, right? Well… there’s a little more to it than that.
2. Glass has many different types
What most people aren't aware of are the number of different glass types that now exist on the market, as well as the variety of different jobs they're able to perform.
In alphabetical order, you can get Anti-sun, Decorative, Heatlock, Obscure, Safety, Security, Self-cleaning and Sound Reduction glass – each coming with many variants that offer their own unique strengths.
We're deviating slightly as not all types of glass are relevant to double glazing and equally as important as the type of glass is the layer or tint that is applied to it.
3. What the special tints can do
Currently, the most popular tints are Low-E glass (meaning “low emissivity”) and Low Iron glass. In short, Low-e glass has a tint that reflects heat, so by being placed on the inner pane of your window, it stops heat sneaking out and keeps your home warmer. Low Iron glass does the opposite and its tint allows short wave solar gain through, so placing it on the outer pane of your window invites heat in.
Still with us?
4. The Argon factor
Sitting in between the two panes of glass lies a layer of Argon gas. Why is this relevant? Well, Argon is denser than air, meaning that wherever there is a wall of the invisible, tasteless, odourless gas, there is a barrier that stops cold air passing through it.
As a rule, the thicker the wall, the more air it stops, but as windows are restricted by how thick they can logistically be, many tests have been run to find an optimum distance within the window. A space of 20mm is ideal, but a lesser distance can still be effective depending on the glazing of the window.
Cool or what?
5. Air tightness
You can have the greatest window in the world, but if the glass is loose within the casing or if there are gaps between the window casing and the frame, warm air will leak out of the house and cold air will pour in from outside. Therefore, windows must fit perfectly into the space around it. Any gaps will act as a weakness and hinder the overall performance of the window.
And there you have it. Double glazing explained in 5 simple steps.