Stainless steel is an excellent choice of material in the specification of a handrail and balustrades, but it’s important to consider a number of factors to make sure you maximise its performance and aesthetic appeal. We explain the ins and outs of stainless steel balustrades…
What is Stainless Steel?
Stainless steel is a group of corrosion-resistant steel alloys which by definition comprise a minimum of 10.5% chromium. The chromium reacts with oxygen to produce an oxide film on the surface which provides corrosion resistance. Unlike coatings such as paint or galvanising, this passive film re-forms if it is damaged by abrasion, thereby continuing to protect the metal.
What advantages does stainless steel offer?
Corrosion resistance is not the only advantage gained by using stainless steel for a handrail and balustrades. They also offer the following attributes:
- Resistance to fire and heat with the ability to resist scaling and retain strength at high temperatures.
- Metallic sheen provides high aesthetic quality.
- Strong and extremely hard wearing (no ongoing maintenance required) for life-cycle costing benefits.
- Easily fabricated with mechanical properties (including elongation and work hardening) which can be used in forming applications to meet complex design requirements.
- Resistance to unsightly staining and easy to clean.
Stainless steel is known for the quality of its finish, making it a popular specification for high-end projects. However, the roughness of the finish can vary and determines the long-term performance of stainless steel. Most ‘dull’ polished finishes result in surface roughness, depending on the type of belt/pad and polishing grit applied. Coarse polished finishes are prone to grooves which accumulate chloride ions that damage the passive film, reducing resistance to corrosion. A number of manufacturers offer ‘brushed’ or ‘satin polished’ finishes – the latter is better for corrosion resistance and infuses the stainless steel with an elegant shine. Unidirectional polishing can further improve the visual appeal of the finish.
Suitable grades for stainless steel balustrades
Certain grades of stainless steel are used in the built environment. Grade 304 is used when you need a handrail and balustrades in dry internal environments. Grade 316 (regarded as the standard ‘marine grade stainless steel’) is used when you need a handrail and balustrades for external environments, which require greater corrosion resistance.
Construction and installation
The construction of a handrail and balustrade in stainless steel is carried out by one of two methods: on-site fabrication or modular components which are manufactured off-site and assembled on-site. Fabrication often involves hot works such as welding which consume more energy and create more mess. It also leaves weld seams which are generally removed by grinding, a process which can affect the quality of the finish and lead to the associated problems outlined above. By contrast, modular systems – with off-site manufacture in factory conditions – offer a range of advantages which we outline here.
When using modular systems, it is important to consider the material and type of fixings which are used to connect and assemble the components. If a bolt, screw or other fastener is a different type of metallic material to the handrail and balustrades, this can cause galvanised corrosion accelerating the deterioration of the less noble material. This often results in unsightly rust-coloured leakage around the fixing/fastener.
Some modular systems are connected internally – for example, using ferrules – which obviates the issues caused by galvanised corrosion, as well as providing a smoother finish to the touch on handrails.
Stainless steel is more expensive than most of the other materials and metals commonly used for handrails and balustrades. However, savings can be achieved by combining it with less expensive components – for example, rather than use stainless steel rail infills, you could opt for glass panels or tension wire instead. Alternatively, you could combine stainless steel with powder coated aluminium – the coating prevents galvanised corrosion and provides a warm-to-the-touch finish with low thermal conductivity.
For further information about the design and specification of stainless steel handrails and balustrade please contact our team of technical experts on 01653 695 721 or enquire here.