Shaped secondary glazing

This premium option is mainly chosen for older buildings which feature shaped or curved windows and where a sympathetic design treatment is needed for any secondary glazing.

Shaping involves the use of irregular angles and even units with more than four sides.

It is also possible to shape horizontal sliding units, hinged casements, lift out units and fixed panes.

Windows with arched heads can be accommodated by vertical sliding units and fixed and hinged casements and bull’s eyes with fixed or lift out panels.

Curving on plan is achieved with fixed panels or hinged casements.

The range includes:

   * Series 20 Slimline

   * Series 40 Heavy Duty

   * Series 45 Slimline

   * Series 90 Heavy Duty 
 

Shaping involves the use of irregular angles and units with more than four sides. There are limitations but, it is possible to shape horizontal sliding units, vertical sliding units hinged casements, lift out units and fixed panes.

Curving on elevation

This allows sympathetic treatment of windows that are curved in the vertical plane and includes eybrow windows, full centre arch, semi-circular openings and bulls-eye windows.

Vertical sliding
Series 20 and Series 90

• Both the slim Series 20 and heavy duty Series 90 vertical sliding systems can have arched heads up to a full radius.
• The frame construction and balance lengths will limit the travel of both sliding sashes and consideration must be given to access for cleaning and external window operation.
• The minimum radius for Series 20 is 450mm and for Series 90, 500mm.

Hinged casements
Series 40 and Series 45

• Heads can be curved up to a full radius with a minimum of 450mm.
• Three sided curved casements allow the wings of semi-circular openings to be treated.
• The espagnolette locking system cannot be fitted on the curve and face mounted catches/locks are fitted to three-sided units.
• When a full radius casement is fitted within a barrel vaulted reveal the window height has to be reduced to avoid the shoulder of the opening vent binding on the reveal. An enlarged shaped timber sub frame is normally required.

Fixed & Lift Out units
Series 40 and Series 45

• Heads can be curved to a full radius with a minimum of 450mm
• Three sided curved panels can be produced to treat the wings of semi-circular openings
• Fully circular units are available with a minimum radius of 500mm for series 40 and 450mm for series 45.
• Locks and restrictor stays are fitted to Lift out units. Care must be exercised when the units are removed for cleaning.

Curving on plan

This allows treatment of windows that curve inwards

Hinged, Fixed and Lift out

• Series 40 range can be curved on plan to meet a minimum radius of 1800mm
• Curved glass is toughened or laminated
• The joint between the vertical and horizontal curved plane will show a slight overlap.
   

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.