Windows are an integral element of a building and as such, they provide insulation, ventilation, lighting and privacy, both during the daytime and nighttime. They allow the building occupants to enjoy the views of the neighbourhood and, at the same time, keep them hidden from nosey neighbours. Although they may be perceived as one of the most vulnerable points of access for intruders to enter a building, they play an important role in ensuring one’s house safety and security. And to be honest, most of these features are achievable not only thanks to the window’s frame or profile but also due to window glazing. Over the years, window designs have evolved because of technological advancements taking place. The same refers to window glazing. Nowadays, window glazing is available in a variety of choices to suit everyone’s needs and requirements. Beyond the energy efficiency gains, the right window glazing may surely impact on other performance areas, such as, among others, the design, acoustics, fire resistance and overall light levels. When looking at types of glazing, it is also crucial to consider such key benefits as security and privacy.
What is the glazing of a window
But let’s start from the basics, shall we? While researching window glass types for your home or business, you’ll often come across the term ‘window glazing unit’. It is sometimes misunderstood that glazing refers to the glass with added special coating – this is not true. Window glazing is essentially the part of a window made of glass. To be precise: the word glazing refers to the glass that is installed in the window frame. There are three different window glazing options. One sheet of glass is a single glazed window, two window glazing panes create a double glazed unit in the window and with three panes of glass, you get a triple glazed window.
Despite the fact that window glazing and window panes seem to be interchangeable terms, they, in fact, are not. The reason is there are multiple window panes types available. What separates one from another is the way they are manufactured, for example tempered glass (made from annealed glass via a thermal tempering process) or laminated glass (made up of glass layers held together by a polymer interlayer). Glazing, on the other hand, is the broader term that refers to a pane of glass, but not usually the specific type of manufactured glass.
Types of window glazing units
A glazing unit is a structure that consists of at least two panes of glass that create an internal cavity filled with air or other gas, separated from each other and sealed around the perimeter by a warm edge spacer, sealants and vapour-absorbing substances. Traditionally, we differentiate them into three window glazing options based on the number of glass panes: single glazed windows, double glazed windows and triple glazed windows. Nowadays, there is a lot of discussion over double glazed windows versus triple glazed windows and their benefits – we have also covered this topic broadly in one of our previous blog posts HERE. At this point, we just want to sum up the most important features of these three window glazing types:Single glazingSingle glazed windows include a single layer of glass. Honestly, we won’t indulge in much discussion about this type of window glazing, as single glazed windows are the least energy-efficient ones. They are not much effective at filtering-out noises and allow more heat loss than any other window glazing explained in this blog post.Double glazingDouble glazing types are designed with two glass panes, ensuring much better insulation and noise control. These glazing units would be perfectly enough for rooms which are used less frequently, or are not kept at a higher temperature. They are also appropriate for rooms located in the more sunny southern part of the house. One of the main benefits of double glazed windows is their price – it is much lower than in the case of their triple glazing counterparts.Triple glazingAs triple glazing consists of three glass panes, it obviously offers much better insulation and maximum energy efficiency. That’s why triple-glazed windows are highly recommended for modern buildings and energy-saving homes called passive houses. In fact, they are from 20 to 30% more energy efficient (with U-value from 0.9 W/m2K – passive windows) than the double glazing options. The third additional pane helps in noise reduction, too.
Window glass types by function
Once we have discussed glazing types windows are equipped with, it is time to focus on numerous window glass types and names. It is good to bear in mind that the type of glass you choose for your windows will affect their functionality and appearance. Knowing the following types of window glass can help you make your decision during the window buying process:
- Laminated glass (VSG) – it effectively reduces the risk of burglary or theft. If it breaks, the pieces of the glass stay attached to the film, helping to avoid injuries to nearby people. PVB (polyvinyl butyral) foil makes it difficult to break through the glass, too.
- Tempered or toughened glass (ESG glass) – it is characterised by increased resistance to crushing or breakage. However, if it breaks, it falls apart into small pieces with blunt edges, which minimises the risk of injury.
- Matt glass – it is achieved with the use of matte PVB mat foil (in VSG panes), thanks to the technology of etching the surfaces with acid (Satinovo) and by sandblasting.
- VSG coloured glass – it provides architects and designers with complete creative freedom. There are various colour options of various intensity available, including transparent, translucent or non-transparent ones.
- ESG coloured glass – its colour is obtained by applying a layer of enamel to one of the sides of the glass pane.
- Frosted glass – it is produced by the sandblasting or acid etching of transparent sheet glass. It has 10-20% opacity. It comes out as translucent because of light scattering during transmission – and it still obscures visibility even as it transmits light.
- Ornamental glass – translucent, colourless or body-tinted glass. It provides wide possibilities in terms of design and allows you to fully personalise your space. Depending on the pattern, there is greater or lesser transparency.
- Selective glass – it reduces the flow of solar energy entering the building and at the same time maintains a relatively high level of light transmission.
- Absorbing glass – it absorbs the sun’s rays, reducing light transmission and the amount of solar energy inside the building.
- Reflective glass – it creates the mirror effect and reflects light radiation from the glass, allowing for the simultaneous reduction of solar energy infiltration.
Different window glass types and prices
All the above-mentioned window glass types are used according to their functions, including decorative, sound absorbing, fireproof, safety and solar control ones. Apart from that, you can find some real technological innovations, like smart glass, also known as switchable glass, that allows for the opacity of the windows to be adjusted at the touch of a button – from opaque to completely transparent. There are also self-cleaning panes available – they provide natural cleaning thanks to the action of UV rays and rain and are ideal for hard to reach places.
While choosing the right window panes that will fit you and your house the most, focus on the purpose of the window, the building location, features desired and obviously, your budget. Window glass prices depend heavily on the glass size (per square metre), thickness (in mm), type, tint, and features. At Fenbro, we offer various solutions, each of them suitable for a different residential or commercial application. Have a closer look at the window pane offer on our website!