Types of Glass that Worsley Glass uses in the PVC Windows, Doors and Conservatories
Alarm glass:
This is a security glass that is specially laminated with a wire of 0.1mm between the sheets of glass. The wire is part of an electrical circuit that is set off if the glass is damaged, and is therefore ideally suited to secure commercial or industrial premises.
Anti-reflective glass:
Standard float glass undergoes a dipping process that coats it with metal oxide layers. The result is that it reflects a low percentage of light, but still allows for clarity and transparency. Anti-reflective glass is utilised in buildings like glass walled restaurants where night time sight is important. The coating also increases the glass' resistance to damage.
Body tinted glass:
During the float glass melt process chemical colorants can be added which tint the colour and increase absorption from the sun. This helps minimise the solar radiation that enters a building, keeping it cooler inside and protecting furnishings from fade. Body tint glass has the added bonus of making a building look unique and contemporary, creating a lasting impression for business HQs.As an example of the colorants used; to create a purple exterior, manganese is added, while pinks and reds can be produced from selenium.
Electrochromatic glass:
Also known as Smart Glass, Suspended Particle Displays (SPD), electrified liquid crystal, thermotropics, photochromics or photochromatics; this type of glass aims to eliminate the need for blinds by changing from clear to dark as the sunlight intensifies. It contains an electric current that can be manually turned on or is that automatically responsive to the light.
The intensity of the sunlight triggers a low voltage current which charges a minutely thin coating on the surface of the glass. This causes the electrochromatic layer to gradually change from light to dark. This highly beneficial for glass buildings as it reduces cost and awkwardness of window coverings and reduces the solar heat and UV radiation.
Fire resistant glass:
There are two types of fire resistant glass which perform with varying degrees of success:
- Heat transmitting - This incorporates wired glass and reinforced laminated glass which offer protection against flames and inflammable gases, but only for a short while. It does not prevent heat being transferred to the other side of the glass, so it will be hot to touch.
- Fire insulating - This glass is capable of a longer containment period of flames, gases and smoke, and also prevents heat transmission to the other side of the glass.
Float glass:
Standard flat, clear window glass is called float glass; named after the manufacturing process that creates it.
During production, soda lime glass, calcium, silica sand, soda, oxide and magnesium are mixed together and melted in a furnace at a temperature of around 1500°C. The molten glass is then poured into a molten tin bath. The tin is fluid but the glass is still viscous, so they do not mix and instead stay flat like the contact surface between them. The glass partially cools, and is then put into a lehr, (annealing chamber), where it undergoes a controlled cooling process until it reaches room temperature.
Laminated glass:
Another security glass, this combines two plus glass sheets that sandwich one or more layers of PVB plastic or resin. If someone tries to break the glass, the internal layers bond fragments together and continue to resist further breakage. For this reason it is also installed to delay the spread of fires.
Low E glass:
Low Emission glass has been developed as an energy efficient option for domestic and residential installation. It has a metal oxide coating that retains heat generated from within the home, and keeps the cold or summer heat outside. It can be coated with a hard or soft coating, of which the more expensive soft coat is the better performer. The soft coat itself however can show a brown or grey tint and will become damaged with handling. It can therefore only be used in sealed glazed units.
Patterned/Obscure glass:
Glass with patterns is made by a rolled glass process. The partially molten glass is compressed between metal rollers, one of which bears an indent of the intended pattern. The thickness of the glass is determined by the gap between the rollers; whilst the depth, shape and size or the pattern itself will determine how much light and reflection is available through the glass. This is expressed as a distortion number rated from 1 (little distortion) to 5 (high distortion).Only one side of the glass is patterned and this is usually positioned on the inside so that external dirt can be easily cleaned off.
Obscure Glass Examples
Arctic
Autumn
Chantillyl
Charcoal Sticks
Contora
More Obscure Glass
Reflective glass:
Starting with float glass, a metallic coating is added that serves to minimise the solar heat that passes through. The metallic coating has a mirror effect, and so reflects back the light and prevents passers by seeing into the building. It is used mostly in building facades, and is produced in one of two ways:
- Pyrolitic (on line) - During the float glass process, semi conducted metal oxides are adhered to the glass while it is still hot in the annealing lehr. Unfortunately, these hard coatings are quite harmful to the environment.
- Vacuum/magnetron (off line) - Metal oxide layers are applied to the glass under a vacuum. This is a soft coating, and as with the soft coat low E glass it is sensitive to harsh conditions. It must therefore be used on the inside of the glass.
Self-cleaning glass:
This revolutionary process is created by coating float glass with a photocatalytic application that is chemically bonded to the exterior of the glass. When the sun's UV rays hit the glass, the integrated coating dissipates organic dirt through what is known as the photocatalytic effect. Self cleaning glass also has hydrophilic properties, which in layman's terms means that when it rains, it flows down the coating as a sheet and it washes away the dirt broken down by the sun; unlike normal float glass. While inevitably these high tech windows cost around 10 - 20% more than standard float glass, you will save money on window cleaning products, time and effort. However, they may need a brief rinse if there is a particularly dry spell.
Toughened glass:
Tempered or toughened glass undergoes a different process to annealing that makes it around three times as strong as normal float glass. As soon as the glass is removed from the furnace, it receives a continuous and uniform air quench, where air is blown across it to cool it to a temperature of around 400 - 600°F and thus causing the material to harden. The tempered glass is then fit for security applications. It is tougher to break than ordinary glass, and when broken just shatters into small fragments that avoid causing major harm.