Balustrade Glass Regulations Explained
Wondering what regulations there are that concern the design, installation and use of glass balustrades? Look no further as we have packed them into this handy guide. The technical requirements for balustrades are defined by BS 6180 : 2011 and Building Regulations Document K and Document M. These documents sometimes contradict each other and also contain ambiguities.
Is glass a permitted material for balustrades?
Glass Balustrades are a feature of staircases, Juliet balconies, balconies mezzanines floors and can be found inside and outside of both domestic and commercial buildings.
The reasons why glass is becoming increasingly popular as a balustrade material is because;
- Glass is rigid and strong, able to resist pressure and force
- It does not bend, buckle or break when a reasonable amount of pressure is applied
- It is durable, as well as being suitable to the area in which It is being used.
Metals such as stainless steel and mild steel are popular choices, as is wood, along with glass either on its own or combined with these materials to create a stunning balustrade. In the UK, aluminium is not used very often. This is because UK building regulation is more strict than anywhere else in the World.
Which types of glass can be used?
UK regulations are unclear about what type of glass may be used. This is unlike Building Regulations elsewhere in Europe which always specify Laminated Glass.
The tempering or toughening of glass involves subjecting it to high heat, around 700°c, and cooling is quickly, a process known as quenching.
The quenching process takes around 60 seconds, creating a stronger layer on both sides of the glass. This locks in tensions in the core of the glass with this simple, effective process increases the strength of glass four times.
Tempered glass is known as “safety glass” because this process means that it becomes much less brittle but will shatter completely when damaged. It will ‘break safely’ meaning that rather than razor sharp fragments, it crumbles into small, ‘granular’ type pieces.
Laminated glass is made by sandwiching two or more glass panels together and having a clear plastic interlayer in-between.
Different types of interlay are used. Some produce glass panels that deflect less than others. Consequently, you must be careful when specifying the interlay with your glass supplier who can assist in this regard. Laminated glass may be made from two toughened panels, two float glass panels or a combination of both.
The idea behind laminated glass is that one panel may break under impact. But the second panel provides continued protection by surviving.
In the UK, tempered glass is used most often. The use of laminated glass is rapidly increasing, however.
The thickness and type of glass used will vary, and depends on the area it is protecting, the impact class required – there are many impact classes for glass, if you need more information contact your Building Control Officer at your Local Authority.
Glass balustrade height
All balustrades are subject to minimum height requirements:
- Internal railing and balustrades in a domestic property must have a minimum height of 0.9m from datum. Datum is defined as the point that is stood on, to the handrail as detailed in Document K
- External balconies must have a height on 1.1 m from datum to the top of the handrail as detailed in Document K
Glass balustrades prevent people from falling by being able to resist both impact and load. This is when there is significant pressure focused on all or part of the balustrade system.
There are three load requirements that need to be met;
- Horizontal loading on the handrail
- Vertical loading on the handrail
- Loading on the infill
Clearly, with a heavy load or pressure leaning against the various components, the balustrade will ‘give’ a little. But this ‘deflection’ must not exceed 25mm.
Measured in kiloNewtons (kN), you need to be aware:
- Domestic balustrades or light use in office situations need to be able to withstand 0.74 kN/m per metre run of the balustrade
- Public areas need to have a higher rating with a handrail pressure of 1.5kN per metre run, doubling to 3.0kN per metre in high traffic areas such as shopping malls and other areas with high density traffic.
It would not be prudent to use tempered glass that is less than 10mm thickness or laminated glass of less than 13.5mm thickness
Need to discuss these regulations further? Contact the friendly, expert team at Balustrade Components on 01543 624780 or use the Contact Us form.