How Effective is Secondary Glazing for Noise Reduction?


Secondary glazing is well-known for its heat insulation qualities. The second window pane creates an insulating gap, keeping warm air in and cold air out. But how about noise reduction? Does the same idea apply to keeping external noise out of your home?

Read on to see how effective secondary glazing is for noise insulation and reduction.

What’s that noise?

Whether it’s traffic, noisy neighbours or some nearby industrial work, external noise can be a nightmare. For most, it’s not just a small annoyance. As well as ruining conversations and forcing you to turn the TV volume up, it can keep you awake at night again and again. Can secondary glazing help?

In short, yes. Recommended by Historic England, secondary glazing consists of an internal window, fitted to the window reveal or inside wall. The gap between the original window and secondary glazing window acts as a thick barrier to external sound. Rather than a single window letting noise into your home, windows with secondary glazing prevent sound waves from penetrating.

Getting technical

So, how much sound can secondary glazing actually remove? With the right specification and materials, it can reduce noise pollution by as much as 50 decibels. In real terms, that’s 50% of the noise eliminated. Yes, half of the traffic, neighbours and construction noises can be prevented from entering your home. Using specially designed acoustic glass, secondary glazing experts can completely optimise the efficiency of your windows.

Secondary glazing vs double glazing

How does this compare to double glazing? Many people assume double glazing is as good as it gets for noise reduction. In fact, secondary glazing can be up to five times better at tackling noise pollution. Double – and even triple – glazing has multiple panes of glass separated by a gap typically less than 20mm. In contrast, secondary glazing leaves a gap conventionally above 100mm. The greater the gap, the wider the barrier for sound waves, and the less sound makes it through.

The thickness of the glass is also important. In double glazing, the two panes are generally the same thickness. This creates a phenomenon known as sympathetic resonance. Vibrations in one glass pane pass more easily through others if they are similar in thickness. By using layer of glass with a different thickness to the window, sound waves are dissipated, meaning less gets through. It doesn’t have to be a case of ‘one or the other’ though. Homes with double glazing already installed can benefit from secondary glazing.

Over to you

If you want to reduce the noise pollution in your home, Clearview can help. We are secondary glazing experts. Using specially designed acoustic glass, we can install effective sound-reducing secondary glazing in any property. We’re experienced across the board. So, whether it’s residential, commercial or even a heritage property – we can provide exactly what you need. Sound good? Put us to the test. Get your free, no obligation quote today.

Discover How To Reduce Noise Pollution By As Much As 80% 

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Clearview secondary glazing - the solution to significantly improved acoustic and heat insulation to your property, making your home or offices more comfortable, secure, greener and cost efficient to run. Achieved without the disruption of replacement windows, and without damaging the character of your building.

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