If you live on a busy road or suffer with the noise of nearby schools or parks, you may wonder how you can avoid having to put up with it. Double glazing can work very well to drown out some of the noise, so it might make sense to assume that triple glazing would result in further reduced levels. But does it really and will be worth the increased costs?

How does sound work

Sound is measured in decibels (dB). The lower the sound the lower the number of decibels. The loudest sound possible is at 194dB and noises above 100dB are regarded as dangerous enough to cause damage to our ears. At home the types of noises you might be subjected to would include traffic noise at around 60-70dB which compares to normal conversation at 60dB.

Sound travels along sound waves with the noise becoming quieter as it moves further away from the source. Sound waves can travel through most things, but are slowed down by barriers such as fences, walls, trees and of course windows. The thicker the barrier the longer those sound waves become and the quieter the sound.

How do windows stop sound?

Essentially the windows work as a barrier – slowing down the sound wave, stretching it out and causing it to become quieter. Double glazing with two panes of glass will significantly reduce the sound, while the three panes of glass you get with triple glazing will add a further barrier to the sound. In fact it is possible to deaden the sound even more by adding further acoustic layers of coating between the glass.

Other ways windows can prevent sound by getting through is by varying the thicknesses of the panes of glass. This works by changing the shape of the sound waves as it passes through the pane – effectively breaking up the noise. The gap between the panes is also an important factor – the thicker the better.

Does triple glazing really work?

This depends entirely on the construction. We have already pointed out that the thickness of the barrier to noise is important, but also the thickness of the panes and the gaps between. If these are varied the reduction in noise will be even greater. So in theory, a double glazed unit with two different thickness panes and a gap of 30mm, might actually offer more protection than a triple glazed unit with equally thick panes and gaps of just 10mm.

The take-away

It seems that if noise reduction is your main concern and you want to be sure you are buying the best product for those needs, you should be prepared to buy specialised windows, whether they are double or triple glazed. These units may have additional layers, coatings on the window panes, varied thicknesses of pane and varied gaps between the panes.

Also don’t forget that noise will travel through walls and plastic – so ensure the frames of your windows are insulated and your walls are thick enough to slow down that noise.