Balustrade Posts: How Strong Do They Need To Be?
Balustrade posts and railings have become increasingly popular architectural features. Not only are they safe and durable, but well-designed balustrades can add more than you might expect to the aesthetics of a building, while at the same time creating privacy for its inhabitants and users.
Many people are confused about what balustrades are and how they differ from fences, railings, and handrails. A balustrade is essentially a railing system made up of supporting posts called “balusters”. These balusters are connected to form a unit with a handrail positioned along the top. The term “balustrade” refers to the completed construction of the balusters and handrail, which together form a complete railing system.
What is the purpose of a balustrade?
Balustrades (or railing systems) can be used for decoration, safety, privacy or a combination of all three. They provide support for people who can’t walk or move around easily and help cordon off certain areas for clarity, safety or privacy. All balustrades and railing systems do more or less the same job. However, there are crucial differences in their construction which alter how they can be used.
The strength of your balustrade posts will depend on variables, such as:
Most balustrade posts are made using a combination of steel or aluminium and glass. All of these materials are durable, easy to clean and don’t block the light, creating what architects refer to as an “open field of view”.
When used in balustrade design, glass needs to be thick enough to support the balustrade construction. The thickness of the glass panels varies on the design and location of the balustrade posts, as well as what type of building they are attached to.
There are two types of safety glass used in balustrade construction:
- Toughened (or tempered) glass
- Laminated glass
Toughened glass gets heated to around 700 degrees Celsius during the manufacturing process. It is then rapidly cooled, or “quenched”, to create an outer later on the panel, making it around five times stronger than regular glass. If the glass breaks, it will shatter into small pieces rather than large shards that could cause serious injury. Toughened glass panels framed by balustrade posts should be around 10mm in thickness.
Laminated glass consists of two standard glass panels separated by a resin layer. If the glass smashes, the resin layer will keep the panel intact, again leaving no large shards. The exact thickness of laminated glass depends on the balustrade construction, but around 17.5mm is recommended for most applications.
Stainless steel balustrade posts can also be attached to wire rope systems to complement a modern design aesthetic. A rope system is a great option for those who want to create a walkway on flat ground or give the illusion of privacy without using glass (the system can be fitted to a stainless steel top rail to achieve structural integrity).
Marine-grade stainless steel is often used for areas exposed to water to reduce the risk of corrosion. The material is also used for the most handrails to ensure a safer gripping service. Aluminium is another popular choice among architects and can be used as an alternative to stainless steel for many applications.
The required height of a balustrade post varies according to the building it is being installed on or around. It also depends whether the railings are intended for interior or exterior use. The minimum required height is 1.1 metres from the point of standing for external glass balustrades. If the balustrade is on a wall, however, the height of the balustrade posts needs to be 1.1 metres above the point of a person standing on the wall.
Building regulations specify that balustrades and railings must have a pressure requirement they can withstand before falling. Load pressure is measured in kN/m (kiloNewton per metre).
Load requirements vary according to a building’s purpose and size, but external glass balustrades on domestic properties tend to have a legal load requirement of 0.74kN/m. Your balustrade contractor will be able to tell you the load pressure of your construction.
It’s important to consider the building or outside area’s existing design before erecting a balustrade system. Balustrade posts and railings in schools or hospitals, for example, need to allow people to move around the building safely and comfortably without constructing access areas.
Although balustrade construction doesn’t usually require planning permission, you should always consult a qualified contractor to ensure the design and installation of your balustrade meets the requirements of the space.
Many designers choose balustrades to ensure safety and privacy of a property, but they don’t want to compromise on the view. In this instance, a frameless grass balustrade system would be the best choice, as a glass construction provides support without compromising panoramic balcony views. Glass panels are often available in a variety of finishes – such as patterned or frosted, as long as they are compliant with building regulations.
Some providers give you the option to customise the colour or finish of your balustrade posts. You may be able to select black, silver, grey or charcoal for instance. Stainless steel posts are usually available in either a satin or mirror finish, while aluminium is powder coated. Other balustrade customisation options might include built-in lights, a choice of handrail, and a selection of corner posts and caps.
Some balustrades are constructed purely for aesthetic purposes, while others are paramount for safety. For example, when they are positioned around stairs and lobbies or balconies, balustrade posts prevent people and objects falling from a height.
Balustrade posts are often used as swimming pool barriers to prevent people from falling into the pool. Depending on the structure, they can also help keep a pool clean by limiting the amount of debris blown into the water. Balustrades are often used for privacy for outdoor pools, often with tinted or frosted glass panels. Custom panels can also add to the aesthetic of a garden or outdoor swimming area.
Installers should also use bolt-through lugs as a safety precaution when fixing glass infills, as traditional clamp lugs may lead to glass slippage over time. Not only would these lead to costly infill replacements, but they also pose a safety issue.
How strong do your balustrade posts need to be?
As you can see, the required strength of a balustrade post is dependent on various factors – including building type, purpose, safety precautions, materials used and aesthetic preference. There is no one strength requirement all balustrades must adhere to, but installers must still comply with government building regulations (BS6180:2011).
Balustrade posts and handrails appear in some form in almost all buildings and outdoor areas. Whether they exist as critical safety structures or design features, balustrades should be strong, sturdy and durable.
When choosing a balustrade for your building, it’s important to consider the best materials, design and aesthetic elements for the project. At SHS Products, our fully trained CAD technicians will help you select the best balustrade posts and railings to accommodate your needs, while ensuring you remain compliant with building regulations. For more information, call us today on 01922 743842.