Types of Secondary Glazing

Lift Outs

Economically, the Lift Out is the most cost effective type of secondary glazing available. Its most common application is where limited access to the primary window is required, for example a window which has been installed with the sole object of providing light to a room.

As well as economical, the Lift Out is also the most basic form of secondary glazing. As its name implies, it simply lifts out of a secured channel. For practical purposes, it is advised that the sash size be considered since the weight of glass must be of manageable proportions. Each sash is manufactured with double brush pile seal, further increasing the thermal and sound insulation properties.



Hinged Units

When it comes to providing an unobtrusive secondary glazing system, the hinged unit provides the most appropriate solution, since there are no transoms or mullions to spoil the view. The reduction in noise, and improvement in thermal insulation, greatly enhances both the living and working environments.

The hinged unit can be manufactured in two main types. The single hinged unit opens on a restricting friction stay. Where the application is on a larger scale, the friction stay is replaced with a butt hinge. We have developed and rigorously tested a variety of butt hinges for differing leaf weights. The double-hinged unit has been primarily designed to fit in front of larger Windows or French Doors, utilising the same range of hinges.


Horizontal Sliders

The Horizontal Slider is undoubtedly the most frequently used type of secondary glazing. Its uses are therefore widespread, being applied to high-rise or low-level commercial properties, historic buildings as well as all kinds of domestic dwellings. The Granada system provides sensitive solutions to the problems created by noise and sound pollution.

Generally available in two, three or four panelled versions, the sashes are fitted with brass rollers, ensuring the smoothest sliding action. Twin brush seals provide excellent high sealing efficiency. This has been scientifically proven to eliminate draughts, increase thermal insulation and give greater improvements to the security of the primary windows. The security issue is further enhanced with the use of the latest locks and handles.

Vertical Sliders

Due to the characteristics of the existing primary window, the Balanced Vertical Slider is the most complex type of secondary glazing system. It is applied generally to older properties. It is particularly suited to the refurbishment and upgrade of the nation's architectural heritage.

The individually pre-tensioned spiral spring balances control the motion of the sash, enabling infinite vertical positioning. This design provides ease of movement and has been specially developed to withstand decades of wear and tear. Tilt in versions can be pivoted through almost 180 degrees. This is especially useful for cleaning but just as importantly can be crucial when considering fire escape requirements. All variations of Granada's exclusive secondary glazing styles are completely compatible. Each type can be easily used with another no matter what the application may be.

Technical Details

The Aluminium alloy used to construct the secondary is extruded to exclusive Granada designs from 6063T6 alloy to BS1474. The aluminium standard finishes are:- Natural anodising to AA5 (silver)- BS3987, Polyester Powder coat to BS6496. in EP white / Van Dyke brown these have a high gloss finish. 60 microns. Any RAL colour can be produced should something different be required.

A Polypropylene draught strip to BS7386 is used to ensure the secondary is draught-proof. The gaskets used to secure the glass are extruded to BS2782, in standard black, a white 4mm gasket also available. Various types of glass can be used to improve heat retention or for better acoustic control.

Secondary Glazing

Listed buildings and projects where conservation of the appearance of original windows is required can benefit from the greatly improved thermal efficiency and noise reduction offered by modern secondary glazing techniques.

Granda Secondary GlazingHere, using the well known Granada system, the expertise, and experience of Climax can be harnessed to achieve optimum levels of energy conservation and heat retention by installing unobtrusive secondary glazing which also provides easy access to the original window for cleaning or maintenance. In most instances, Climax secondary glazing designs can be made invisible from the outside of the property.

A wide range of high quality lift-out, horizontal and vertical sliding, arched or curved head secondary glazing units can be individually tailored to fit virtually any building whatever its age or architectural style.

Our secondary glazing is supplied and fitted fully assembled and comprises of an aluminium outer frame joined to a seasoned hardwood surround which allows for a neat, unobtrusive installation even in the most difficult situations. A range of hardwood sub-frames and scribing trims can be used to assist face fixing, reveal fixing and the coupling of units. Our secondary is suitable for all types of premises including grade one and two listed buildings, schools, colleges, hospitals, universities, hotels and commercial buildings i.e. offices.

The Benefits of Secondary Glazing

  • Heat Insulation - Standard secondary glazing greatly increases the thermal rating of the window - Low "E" glass can be used to equal or better the thermal performance achieved by replacement sealed unit double glazing - Saves energy - Reduces heating bills - can meet the requirements of building regulations document "L" for the thermal standard of new & replacement windows - Improved energy rating for the new Energy Performance Certificate for the Home Buyers Pack.
  • Sound Insulation - Standard Secondary Glazing achieves a significant reduction in noise entering from outside - Specialist glasses, such as Stadip ® Silence Laminated Acoustic Glass, are especially effective against road, aircraft, rail & in fact any type of noise.
  • Cost - Installing Secondary Glazing is much cheaper than replacing windows.
  • Security - Standard Secondary Glazing adds considerably to security - it can only be opened from inside - The addition of toughened or laminated glass & additional locks will further increase window & door security.
  • Dust & Rattles - Because the Internal Secondary Glazing is fully sealed there is very little air movement within the cavity, thereby virtually eliminating the ingress of dust & cutting out any rattling of the primary window.
  • Draughts - No more draughts from windows and doors once they have been fitted with Secondary Glazing.
  • Protect Carpets & Soft Furnishings - Where secondary glazing with laminated glass is specified it protects carpets & soft furnishings by filtering out the colour fading effects of UV light.
  • Character - Secondary glazing can provide all of the heat & noise insulation that modern living demands whilst protecting the character of your home by retaining the original timber or metal windows.
  • Historic Buildings, Conservation Areas & Listed Buildings - Other than in very exceptional circumstances secondary glazing is accepted & indeed welcomed by Planning Officers as a much better alternative to replacing windows & doors in conservation areas & listed buildings.
  • Maintenance - Maintenance for secondary glazing is minimal.

Low line lift out detail
Low line lift out detail
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An inward opening secondary french window with a semi-circular fixed light above.
An inward opening secondary french window with a semi-circular fixed light above.
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A hinged secondary window open
A hinged secondary window open. Click photo to view larger

2 part horizontal slider over traditional casement window2 part horizontal slider over traditional casement window (in closed position)
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A 3 panel horizontal slider with right sash open
A 3 panel horizontal slider with right sash open
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Balanced vertical sliders over sash windows
Balanced vertical sliders over sash windows - 3 in a row
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Tilt-in balanced vertical slider
Tilt-in balanced vertical slider
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