Secondary Glazing Guidance

Where Is It Used?

• Busy areas where traffic noise is a nuisance - even when double glazing is already fitted.
• Ideal for use in Listed Buildings, Heritage / Conservation areas and period properties.
• As a cost effective alternative to replacing your existing single glazed windows.
• Leasehold properties, where changing the existing windows may be uneconomical.
• Any property where you are unable to modify the existing external windows.
• Any window that needs noise reduction and / or draught reduction.

What Does It Look Like?

Usually they are white, although optionally we can paint them any one of 200 colours. They are made from durable aluminium so they will not rot and require very little maintenance. As aluminium is a strong material the frames can be made slim so that it is less obtrusive. They come with covering trims so you don't see any of your fixing screws and the units are often pre-drilled for easier installation. Also, our secondary glazing can be curved to form arched secondary glazing windows. Our luxury subframe system, comes with trims and a wooden subframe to help blend the frame and finish it in a clean and aesthetic pleasing manner that contributes to making our secondary as discreet as possible - seen right.

The Optimum Air Gap - Simple Yet Effective

A simple yet effective way to optimize the reduction of both heat loss and external noise is to install your secondary glazing to allow around a 100mm air gap between the Secondary Glazing and the existing windows (glass to glass). This is the optimum air gap for sound and heat insulation due to the length of sound waves and the rates of transferal of heat through air. We have a deeper SF3 and SF4 subframe specifically for the purpose of Reveal fixing the Secondary Glazing in this way.

Resonation Factor

We recommend that you use a different thickness of glass in your secondary glazing than is in your existing windows, if you wish to achieve maximum sound insulation. Different frequencies of wave length (of sound) will penetrate glass of different thickness more easily.

If the glass in the existing window is 4mm single glazing and the secondary glazing uses 6.8mm glass, it will not only trap sound in the thickness of the glass, but since the resonation factor of the two pieces of glass is different, it will provide a further barrier against different frequencies of sound, compared to the 4mm glass. This is due to the fact that the frequency at which sound oscillates through different glass, compared to the rate at which it dissipates the sound waves energy is different.

Secondary Glazing Guides

To request brochures or technical manuals for our Secondary Glazing in hard copy format you can either email us or contact our office directly by telephone.

Please see our contact page for details.