If you're having glass balustrades built, they will typically be constructed using one of three types of safety glass: laminated, toughened or laminated-toughened glass. The choice of which one is right for your project depends on two things: the structure height that the balustrade is protecting and the degree of framing provided by other materials.
Height Difference The Barrier Is Protecting
The first thing to think about is the height difference that the barrier is protecting. Ask yourself: if something fell off of the structure, would it fall more or less than one metre? If the difference between the structure and ground below is less than a metre, then any of the three glass types would work. In many areas, a balustrade is not absolutely necessary for height differences under a metre, though it may be prudent to protect friends and family by constructing one anyway. Your contractor can provide specific details on the guidelines in your region. Once the level difference is higher than a metre, however, stricter rules come into play.
Degree Of Framing With Other Materials
Another factor that influences which glass type is suited to your project is the degree of framing provided by other materials, like steel or timber. Even when protecting a level difference of over a metre, if a balustrade is fully framed, in metal or wood for instance, then any of the three safety glass types are suitable. The reason for this is that, in these cases, the framing is providing the primary support of the balustrade, and the glass panels are only filling in the frame.
The situation is different, though, for semi-frameless or frameless balustrades that protect a height difference of over a metre. In these circumstances, only the third glass type, laminated-toughened glass, should be used because the glass panels are providing the primary structural support. Also, with these types of structures, an expert engineer or contractor needs to be involved in the design to provide guidance.
The primary focus of all these rules and regulations is to keep people safe. Even if the height difference that your barrier is protecting is less than a metre, and so a balustrade is possibly not mandatory, it may still be wise to construct one. A metre, or 100 cms, is quite a distance for anyone to fall, considering that an ordinary desk or table height is about 75cms, or three-quarters of a metre. Your contractor can provide more specific advice for your project, taking into account your particular structure and local regulations.