Secondary Glazing

Wessex Timber Windows are pleased to be able to work with Granada Secondary Glazing who offer a wide range of bespoke aluminium secondary glazing, made to measure and featuring strong, slim and unobtrusive aluminium profiles.

Benefits of secondary glazing

So, what are the key advantages of a secondary glazing install? Fundamentally, it improves and enhances thermal, acoustic and security performance of traditional timber and metal windows.
The beauty of secondary glazing is that it allows a historic building to retain its original character, all whilst boasting 21st century performance.

Acoustic Performance

The most effective way to eliminate external noise.

Secondary glazing has been proven to be the most effective method of acoustically insulating existing primary windows, with weighted sound reduction indices of up to 54dB.

The essence of effective acoustic secondary glazing is based on the following:

– The optimum cavity between the primary & secondary glazing is 150mm to 200mm.

– The difference in glass thickness between the primary & secondary should be circa 50%; i.e. 4mm primary, 6.4mm secondary.

– In particularly onerous cases the cavity can be lined within an acoustic absorbent material, i.e. 15mm high density fibre board.

Thermal Performance

Reduce heat loss by up to 70%.

Another principal reason for the use of secondary glazing is to enhance the thermal performance of buildings. A typical single glazed primary window will achieve a u value of around 5.7w/m2K. By the use of low emissivity glasses we can improve u values to around 1.868W/m2K, and even further by utilising a double glazed sealed unit beyond to a staggering 0.6W/m2K. This improvement demonstrates compliance with both Approved Document L: Conservation of Fuel & Power and BS 8233:2014 Guidance on sound insulation and noise reduction for building.

Horizontal Sliding

Vertical Sliding

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Have a question about Secondary Glazing?

The team are ready at hand to help. Call 01722 744477