How Does Double Glazing work?

Double glazing is a prominent feature in almost all modern homes. As you can see in our history of double glazing infographic. As a technology double glazing has been around quite a long time now and has become especially prominent in the UK over the last 40 years.

A diagram demonstrating how double glazing prevents heat escaping.

The basic premise of double glazing is that rather than using a single sheet of glass two panes are bonded together into a unit, with air in between. This structure means that it takes more energy for the heat inside or the cold outside to pass through the glass unit. In recent years double glazed sealed units have been filled with argon instead of air. Argon is a dense gas, meaning the heat energy has a tougher time travelling through it and escapes more slowly.  If you’ve ever inhaled helium from a balloon and heard your voice go squeaky this is because the helium is lighter than air and the sound is travelling through it faster increasing the pitch, if on the other hand you were to inhale argon it would make your voice sound much deeper. (Although we really wouldn’t recommend it) This is the exact same principle as the heat energy trying to escape your home, because argon is much denser than air, the heat cannot transfer so easily.

A diagram, demonstrating how a warm edge spacer bar works on a double glazed window

Between the two panes of glass around the parameter is a spacer bar, made of an insulating plastic designed to prevent heat loss, as well as keeping the two panes of glass spaced evenly apart. There are different grades of spacer bar available, we use a high-quality warm edge spacer bar as standard, because the outside edge of the unit is the most likely area for heat to escape it is vital to choose double glazing that is made up of high quality thermally efficient components as well thermally efficient windows and doors themselves.

Triple glazing works in the same way as double glazing but as you might have guessed includes a third pane of glass in the unit, further improving the insulating properties of the unit. Triple glazing tends to comprise of thicker units, (we use a 36mm thick unit as opposed to 28mm used for double glazing) to accommodate the third sheet of glass.

To summarise, double glazing works by making it difficult for air, and heat, to escape your home. Good, high quality, well installed double glazing will help to prevent heat loss from our home and help you save money on energy bills.

To find out more about our double-glazed windows visit: www.this-home.net/windows