Our guide to glass types, part 1

What are the different types of glass used in window and doors that you should know about?

It all depends on what the glass will be used for.

Therefore, we advise that you always speak to one of our team members to make sure you are getting the right product for your needs.

Let’s start with a very practical, so called “Self-cleaning Glass”.

WHAT IS SELF-CLEANING GLASS?

Self-cleaning glass is exactly as the name suggests – glass that keeps itself clean. It uses an organic process whereby dirt is broken down by daylight and is then washed away by rain.

In the first stage, after the installation, within 5-7 days, the coating gets activated. It reacts with daylight to break down organic dirt.

This process is best explained below:

BENEFITS OF SELF-CLEANING GLASS

Glass technology allows to combine different products with different features like Thermal Insulation, Safety, Solar Control and Noise Control. The self-cleaning glass not only brings you a fantastic low maintenance glass cleaning method but also allows you to combine various products for the ultimate in glass solutions. So, for example, when you’re looking for a perfect finish for your skylight you can have self-cleaning glass and also benefit from the solar control technology.

Self-cleaning Glass is best used for windows and skylights.

WHAT IS LOW-E GLASS?

Low-emissivity or Low-E glass, is glass that has a special coating that reflects the infrared portions of light, while letting the visible light spectrum through. This is beneficial because the infrared heat from the sun is reflected away from the building in the summer and during the winter the infrared heat that is already inside a building is reflected back into the space.

By placing low-e glass into a double glazed unit, the individual glass pane temperatures change.  As more heat is retained, the outer pane of glass is not heated as much by escaping energy and the inner pane is keeping more heat in and becomes warmer.  This has two effects.  There are less cold draughts from convection near the windows and the risk of condensation on the glass is reduced.  In this way, low-e glazing not only prevents heat loss, but also encourages warmth during the colder months of the year.

There are two general types of Low-E coating, tin or silver. Tin oxide is applied to the glass at high temperatures to create a very hard and durable Low-E coating. The alternative is a silver coating, which must be enclosed in an IGU so that the silver doesn’t degrade over time due of oxidation.

Low-E coatings often have a slight blue-green tint, so review product samples at varying angles in the daylight to fully understand what the aesthetics will be when installed.

BENEFITS OF LOW-E GLASS

TOUGHENED OR LAMINATED GLASS? WHAT IS SAFETY GLASS?

Laminated glass is made by fusing two or more layers of glass with inter-layers of polyvinyl butyral (PVB) through the use of heat and pressure. This process creates a safety glass.

If the laminated glass is made using sheets of heat strengthened glass, then the sheet of glass will break into large pieces, but it will be held in the frame by the PVB inter-layer. This provides safety, but also adds a level of security since the glass remains in place and prevents a person or object from passing through.

If the laminated glass is made using sheets of tempered glass, then the sheet will fall out of the frame, but will mostly stay together due to the PVB inter-layer. The glass looks a lot like a wet blanket when shattered.

Laminated glass is best used as a safety glass where the glazing must remain intact if it is broken – either for safety or security. Various levels of laminated security glazing are available. For instance, the windshield of a car is laminated heat-strengthened glass so that if an object hits it, the object won’t pass through and injure an occupant nor will the glass shatter into the faces of the occupants.

Toughened glass, on the other hand, is up to five times as strong as ordinary glass which means that it has to be hit much harder in order to break. Also, when it does break, it breaks into lots of small pieces which are much less dangerous.