Vertical sliding secondary glazing

These units are ideal for treating traditional sash windows and are particularly suited to the refurbishment and upgrade of historic buildings.

The sliding sashes are attached to spring balances and are easily opened to any position for ventilation.

The range includes:

Note 1 - Series 20 and Series 60 have a maximum area based on the spring balance capacity. Windows cannot be constructed with both dimensions maximized. Refer to Soundproofyourhome for advice for advice.

Vertical sliding units are ideal for treating traditional sash windows. They all operate with spring balances which support the weight of the sash in all positions.

Series 20 is a slim system that can treat most traditional sash windows. Sashes are not removable but contra-slide to assist cleaning.

Series 60 is a system that allows the sashes to tilt into the room to facilitate cleaning. It is particularly suited to windows with offset meeting rails.

Series 90 is a heavy duty system designed to treat very large sash windows and, through use of thicker glass, provide higher levels of acoustic insulation or security.

Series 95 is a high security system offering resistance against intruder attack or blast

General guidance

• Cleaning. With the exception of the Series 60 unit which has tilt-in panels a secondary sash window should be set with a minimum gap of
• 75mm to allow access for cleaning. Some traditional box sash windows have no reveal and a new timber subframe projecting beyond the architrave has to be fitted.
• Maximum opening. The frame and location of the spring balances will stop the sash between 100mm and 150mm from the centre line. This may affect access to sash locks in the external window
• Arched heads. These are available on Series 20 and Series 90. The length of the balances is reduced to the strike point of the arch and this will limit the travel of the sash.
• Most sash windows can also be treated with hinged casements and this is the preferred treatment for Sash & Case windows in which the lower sash of the primary window, set in the partially raised position, has to hinge inwards for cleaning.
   

Improve the acoustic performance of your windows

At best, a typical sealed unit constructed from two panes of 4mm glass with a 12mm cavity will provide a sound insulation level of around 30 dB. Adding secondary glazing to this typical unit, set an air space of 100mm or more, will provide overall sound insulation of 37 to 40 dB. Because noise level is measured in decibels (dB) and the decibel scale is logarithmic, a 10 dB increase will approximate to a perceived doubling of the noise level. Alternatively a reduction of 10 dB will lower the level of perceived “noise” by 50%.

Secondary glazing systems are already widely used in the commercial and leisure sectors, as well as in all sorts of health, education and public buildings.

When noise is a problem, a double window system will provide noticeably better soundproofing than a single window, even if this is fitted with double glazed units.

They are also uniquely suitable for listed and heritage buildings.

How secondary glazing works

The cavity makes the difference

The gap or cavity between an existing primary window and the secondary unit makes a significant difference to the level of noise insulation. Unlike sealed units where the two pieces of glass are rigidly coupled together, the primary and secondary window acts as independent barriers to noise transmission. As a general rule, the greater the cavity (a minimum of 100mm is recommended) the greater the sound damping effect of the combined window.

Minimise the gap

Gaps around window frames, although minute, still allow the passage of airborne sound that can reduce noise insulation levels by as much as 10 dB. Our secondary glazing units are tailor made to the aperture and come with high performance seals to sound shield the whole window opening and minimise sound leakage.

Multiple glass options

Having the ability to select for purpose from a wide range of glass types ensures optimum performance. For example fitting inner and outer glass with different mass avoids the phenomenon of sympathetic resonance which increases noise transmission at higher frequencies. The greater mass of thick glass improves acoustic performance, particularly at lower frequencies. Acoustic laminate glass has a special interlayer that helps improve high frequency performance – something very well suited to dealing with aircraft noise.

Acoustic liners

Acoustic absorbent lining materials can be fixed between the window frames raising insulation levels by 1 – 3 dB, most effective at higher frequencies.

Professional Secondary Glazing Installation Service available

Surveying, measuring, transporting and fitting secondary glazing is a skilled business requiring experience, product knowledge and specialist tools.

For these reasons we strongly advise that customers use only our professional secondary installation service which is available for projects across the UK. Tackling secondary glazing on a DIY basis is never recommended.

Our experienced professionals and tradesmen thoroughly understand acoustic secondary glazing applications, the materials used and how measure and to fit them quickly and correctly.

The result for the customer is a cost effective service and peace of mind about the acoustic integrity of the secondary glazing project. Contact us today for a free quotation or to arrange a site visit.

Soundproofyourhome is the domestic market operations division of JCW Acoustic Supplies Ltd, the UK’s leading manufacturer and distributor of soundproofing, sound insulation and sound absorbing products.

Sound advice from Soundproofyourhome:

Contact us today and tell us more about the noise problems you are experiencing. Our friendly, helpful advisors will offer you the most appropriate acoustic solutions available to meet your acoustic needs and budget from our comprehensive range.

We believe talking about your situation and offering sound advice based on our vast experience in the acoustics business is a more reliable way of solving your noise problem than simply taking your order or selling “off the screen”, as some companies do.

And if you are in any doubt about issues associated with soundproofing, like weight of materials, structural strength or meeting Building Regulations, then please talk to us – we’ll be happy to help.