Different Types Of Glass Used In Glass Balustrades
If you're planning on glass balustrades for your home, you've probably seen the array of different types of glass mentioned. So how are all these different from ordinary glass and each other?
How Is Glass Made?
Glass manufacture begins with sand, which mainly consists of silicon dioxide. Glassmakers combine the sand with other elements before heating the mixture to temperatures of about 1700 degrees Celsius. Surprisingly, once the molten glass cools, it then transforms itself into something entirely different from sand. The other ingredients might include waste glass, soda ash (sodium carbonate) and limestone (calcium carbonate). To produce its final shape, while still molten, the glass is typically poured into moulds or floated onto a vat of melted tin to create sheets of flat glass.
While this is the general process for ordinary glass, balustrades require particular types of safety glass such as toughened and laminated glass. They also sometimes use decorative kinds, tinted and frosted forms for example. So how are these created differently?
Some of these glass types undergo a distinctive production process. Toughened glass, for example, melts at extreme temperatures before undergoing a quenching treatment. This involves jets blowing icy air across the surface to cool it very rapidly. The inner part of the pane remains hot for longer while the outside cools quickly. This temperature difference causes chemical reactions within the glass that make it about four times stronger than types of glass. It also produces the distinctive breaking pattern of toughened glass, which crumbles into rounded regular pieces rather than dangerous pointy shards.
A type of decorative glass you might see on balustrades is tinted glass, which just involves a simple tweak of the standard manufacture process. To create the tints, glassmakers add mineral oxides to the original mix of ingredients. These might include iron, cobalt and selenium to generate green, blue, grey and bronze-tinted glass. It then undergoes the tempering process to toughen it.
Some other types of glass undergo standard manufacturing, but then they go through additional treatments afterwards. Laminated safety glass results from a heat and pressure process whereby a resin interlayer bonds together two glass sheets. Laminated glass is stronger than ordinary glass, but if it breaks, the interlayer tends to hold the cracked pieces together. Thus they are unlikely to cause injury. Laminated glass can use sheets of ordinary or toughened glass.
Balustrades sometimes use frosted glass. These frosty effects typically result from either an acid etching or sandblasting process, both of which erode one side of an already manufactured glass pane — stencils control which parts of the surface react.