Glazing Manufacturers

When choosing secondary glazing units for a building it is necessary to use a system in keeping with the layout and stuff of the space. There are several proprietary secondary glazing systems available which supply set ups that are configured to suit the specific circumstances of the arrangement.

Proprietary systems typically have coated aluminium frameworks. This enables the layout of slender-line systems that can fit within the depth of the staff bead of an average sash window so shutters and window sills can be saved.

Systems with more substantial framing parts are more powerful and can allow seals, fasteners and counterbalancing. The systems may use an aluminium outer framework fitted to a soft wood soil or seasoned lumber encompasses determined by the layout and repairing components. The provider of these systems supply, fabrication and installation services.

Instead a bespoke system can be made composed of a sub frame, usually of solid wood, into which opening casements or transferring sashes are repaired. Individual glazed windows can be hinged so they fold up like shutters or function similar to sash windows.

The value of conventional ‘respiration’ operation

Most conventional properties are made of porous substances which don’t include the obstacles to outdoor wetness (pits, rain screens, damp-proof courses, vapour barriers and membranes) which are typical in modern building.

Consequently, the porous material in early houses will soak up more moisture, which is later discharged by internal and outside evaporation. When conventional buildings are working as they were designed to, the evaporation will keep dampness degrees in the building material below the periods at which rot can begin to grow. This is frequently known as a ‘respiration’ building.

If suitably maintained a ‘respiration’ construction has certain advantages over a modern watertight building. Porous materials including lime or earth based mortars, renders, plasters and lime wash action as a shield for environmental dampness, consuming it from the atmosphere when humidity is high, and discharging it when the atmosphere is dry. Present day building relies on mechanised eradication to remove water vapour formed by the activities of people.

As old fashioned buildings need to ‘breathe’ the use of vapour barriers and many substances often found in modern buildings must be prevented when making renovations to enhance energy efficiency, as these materials can trap and keep moisture and create difficulties for the building.

The use any modern day materials have to be based upon an educated assessment where the importance of their inclusion and the threat of issues are completely understood. It’s additionally significant that constructions are well looked after, or else progress made in energy efficiency will be negated by the difficulties linked with water ingress and increased draughts.

Slipping systems

Flat skidding systems consist of a couple of panels slipping on glide pads or wheels for bigger windows, with the panels slipping within the framework. Most panels are easily taken out by lifting into the head frame and swinging them outside.

On perpendicular sliding systems, both panels slip within the framework. Some work on spring balances which completely support the weight of the sash and those that don’t can be hard to control and are just appropriate for exceptionally little windows. For sash windows they generally have the top sash innermost, to enhance operability and let the latch on the prime sash to be got to more readily. Tip-in up and down sliding systems enable the sashes to hinge inwards for cleaning. Restrictor stays and braking systems to prevent slipping in the open position can be fitted.

These versions are acceptable where conventional venting is needed.

Hinged systems

Hinged casements are available as single or double leaf with the framework measurements dependent on the window size. Casements in many cases are fitted with restrictor stays.

This sort of system is often used where the entire window would be to be covered to prevent any sightlines on the secondary merchandise. These work nicely for bigger panes, where high compression seals have to optimise sound insulation or to reduce air flow, or where full access is needed for cleaning/repair or to supply a means of egress.

In scenarios with security requirements, multi-point locking can be used.

These layouts are appropriate where routine venting is required. Since the sash jobs into the room when opened for venting this may create a security risk. A restrictor can be fitted to hold the window open at a pre-stated minimum.

Lift outs

A lightweight framework with the panel lifted from the underside to remove. These are best used for windows that are repaired or rarely opened and where availability is just occasional needed for cleaning. In addition, they are useful for windows of uncommon shapes.

Where it’s proposed to remove secondary glazing it is best to have committed storage space accessible.


A lightweight and simple to remove system is a magnetic secondary glazing system. Multi-polarised magnetic strips fitted to UV secure clear cast acrylic join with inverse magnetic strips on the edge of the window frame to hold the panel in position.


Long-Term panels are useful where no access is needed or in combination with other opening panels. Careful thought must be given to the best way to get the glass and the cavity space to clean and keep.

With fully fixed panels to avert the danger of condensation within the cavity can be reduced by supplying ports in the secondary glazing unit.


There are limits but it’s possible to shape all layouts of secondary glazed units to the profile and fashion of the outside window.

Installing secondary glazing

Secondary glazing can have minimal visual consequence if carefully planned. The layout should seek to be as judicious as possible with undersized frameworks hidden from view from the exterior and unassuming from within.

There are numerous different ways of installing secondary glazing to a window opening. Take into account the fashions and specifications as early as possible in the scheme to ensure a successful final result.

A great way to begin will be to contact one of the specialist firms who offer help and guidance on the planned setup.

Whilst the framing stuff may be lightweight glass is deceptively heavy – 10Kg/m² for 4mm thick panes and 15Kg/m² for 6mm. Makers will supply recommendations for size and weight limitations for the safe use of the planned secondary glazing unit.

In the layout progression the following is an indicator of the kind of variables to be considered with crucial issues being the minimisation of damage and ease of use. The intention behind the setup will order the repairing place and kind of glass selected.


The layout of the first window can be used to determine the style of the secondary glazing to be installed. The measurements of the primary window are repaired but the secondary glazing can be designed into manageable sized units.


Secondary windows are usually situated immediately inside the recognized sashes or at an appropriate place within the depth of the window show. An evaluation of the present window opening by the advisor firm will identify the constraints, for example whether there’s sufficient depth in the disclose to find the secondary glazing.


Where shutters or other joinery are current, attentive thought will be needed.

Occasionally secondary glazing can be situated between the primary window and the shutters so the wooden shutters still work. If the wooden shutters are placed within the window reveal it may be possible to install secondary glazing on the room side of the window shutters.

If the secondary glazing cannot be added without making the shutters inoperable the shutters could be repaired shut but not altered so they can be brought back into use at a later date.


Secondary glazing can be visually intrusive outwardly and in if poorly designed. To minimise the visual effect of secondary windows externally, make an effort to make sure that the secondary glazing isn’t smaller than the glazed area of the present window. Make an effort to place any sections in the glazing behind the window assembly railings or glazing bars. The level reflections of modern glass within secondary glazing can be reduced by using anti reflective glass.

Always get a good local glazier.