IGUs – Insulating Glass Units – is a fancy, more formal, title for double glazing (or triple or beyond!).  Manufacturing insulating glass units involves bringing together two pieces of glass, both adhered to a spacer.

Cutting the glass is how we can give you the shape and style of glass you need.

But glass is a brittle material – if it starts to crack it tends to do so completely – so you might think this would make it difficult to cut. But this actually works to our advantage in the cutting stage – the glass needs only to be scored on the surface and then lightly pressured to break cleanly along that line.  (The neatness of that cut comes down to the amount of residual stress held in the glass as it was cooled at manufacture – so cutting quality and accuracy actually starts right back at the float line!)

Although you’d usually see glass in squares and rectangles, we can cut it into almost any shape you can think of. That being said, we know what works and what doesn’t when dealing with glass, so there are a number of cutting guidelines and limiting dimensions that we apply to ensure that the glass will perform well in practice.

Edgework is applied to glass to make it safer to handle, more resilient to damage and better to look at.

Any time you cut glass, you create an edge. As cracks in glass most commonly begin at the edges of the glass, the “quality” of the edge makes a big difference to the resilience of the glass overall. Any imperfection in that edge can provide a point where the stress generated by a load on the glass, even from something as small as someone leaning on it, can become concentrated and start a crack. So edges matter.

Technically the most resilient edge is the edge formed naturally when the glass is cut – a clean-cut edge. In a sense this is the state the glass “chose” to be in when it was scored and broken-out during cutting.

However, because of its near 90 degree corners, a clean-cut edge can be susceptible to crushing, chipping and other incidental damage during further handling, install, and use.

So we can take the sharp corners off the clean-cut glass (arising), or go further to create other forms of edges including rounded, mitred, polished – each suitable for different looks and purposes in the life of the glass.

Many applications of glass call for holes notches and cut-outs to be incorporated into the final design, for example notches for hinges in frameless shower-screens, holes for power-points in splashbacks, cut-outs for pet-doors  and more.

All these things are possible, but just as with cutting and shaping the glass, there are various guidelines and limiting dimensions we adhere to when preparing the glass.

In almost all circumstances, glass with holes, notches and cut-outs will need to be toughened.

All architectural glass starts its life flat from the float line. But it can be bent to suit purposes like creating curved windows, food display cabinets, or balustrades.

It’s a process similar to the initial stages of toughening. A pre-cut or shaped piece of glass is heated to the temperature at which it just starts to cease being solid, and is then rolled backwards and forwards over rollers which have a prescribed curvature in them. From that, you end up with a curved sheet of glass.

Heat treatment refers to Toughening, Heat-Strengthening or Heat Soaking.

Toughening and Heat-Strengthening are essentially the same operation but applied to a different degree. Glass is heated in a specially designed and highly controlled furnace to a point where it just starts to cease being solid, and is then rapidly cooled with air.

This sets stresses within the body of the glass which act to compress the outside few millimetres of the glass. This effectively makes the glass able to “bend” further before it cracks.

The more stress set in the glass, the greater the load it can withstand before breaking. Toughened glass can withstand approximately five times the load of ordinary glass before breaking. Toughened glass can also withstand higher temperature differences across the surface of the glass without breaking due to thermal expansion – making it perfect for splashbacks for instance.

However, the stresses “locked-into” the glass mean that the glass can’t be further altered – attempting to cut or alter the shape of the glass will almost certainly cause it to break.

If toughened glass is broken, it releases a great amount of energy very quickly –  generating the characteristic breakage pattern of toughened glass, where the glass forms small cubes of glass rather than the sharp shards you’d expect from non-toughened glass.

Heat Strengthening

Heat Strengthened glass is almost exactly the same as toughened, but the cooling process is less intense. This results in glass which is less strong, but breaks with less energy, so you get  larger “plate-like” sections that tend to stay in place, rather than crumble away.

Heat Soaking

Heat Soaking is a process for confirming the absence of specific physical contaminants and imperfections in toughened glass that may cause it to “spontaneously” break throughout its life.  This phenomenon is extraordinarily rare, but in many applications it is worth taking steps to all but eliminate this possibility – that’s where heat soaking comes in.

The heat soaking process seeks to simulate conditions where spontaneous breakage could occur if the imperfection was to be present in the toughened glass. That way, any glass will break in the heat-soak oven in the factory, not after it has been installed.

Custom laminating is a bespoke laminating process where pre-worked glass panels are laminated together. Toughened glass can’t be altered post-toughening, so all toughened laminates are custom laminates. They must be in their final shape before laminating occurs.

The laminating process provides almost limitless options in glass configurations. You can have combinations of solar control glass, special interlayers, Low E and coated glass, decorative glass and more.

This is a factory-sealed unit, assembled in controlled conditions, for quality-assured performance and long-life. Various glass types, spacer materials, and gasses can be combined to deliver different appearances, properties, and thermal performance levels depending on what the glass is going to be used for.

There’s a number of preparations and chemical treatments that can be applied to glass post-processing.

One of the most common is painting – colour-backed glass finds its ways into many thousands of homes and other buildings every year as splashbacks and wall panelling. Other treatments applied in the factory can impart properties to the glass to make it water repellent, easier clean, and lower in condensation.

Some uses of glass call for specific visibility motifs to be applied to the glass – this can be achieved by screen printing the surface with a special ceramic paint (generally prior to toughening) or with an adhesive design.

Self-adhesive films that cover the whole surface of the glass are also available – these offer a range of benefits including protecting the surface from vandalism and other damage. They can also play a role in security and impact protection as part of an purpose-designed system.