Nordic Copper enjoys unique characteristics, particularly in terms of safety, sustainability and long-term performance, wherever it is used. With an ‘A1 (non-combustible material)’ fire classification to EN 13501-1, copper is inherently fire-safe. It is also, therefore, rated ‘Class 0’ surface spread of flame in the UK, making it suitable for wall and ceiling surfaces in communal areas. Particularly important today, copper is non-toxic and its inherent antimicrobial qualities make it ideal for touch surfaces.
The natural development of a distinctive patina when used externally defines the material, with colours changing over time dependent upon local environmental conditions, including rainfall and air quality.
Natural Patina
Copper’s exceptional external longevity – conservatively regarded as 200 years – is due to the patination process which ensures extreme durability without maintenance and resistance to corrosion in virtually any atmospheric conditions. This natural development of a distinctive patina when used externally defines the material, with colours changing over time dependent upon local environmental conditions, including rainfall and air quality. Continued weathering can eventually result in the distinctive green or blue patina seen on older roofs.
Obviously, copper used internally or sheltered from rainfall will not change and develop in this way. But the Aurubis ‘Nordic Copper’ range provides all these surfaces straightaway. The factory processes involved are generally similar to those taking place over time in the environment, utilising copper mineral compounds not alien chemical processes, forming an integral part of the copper.
WA Museum Boola Bardip, Perth, Australia, with spiral staircases clad in Nordic Brass copper alloy. Photo – Peter Bennetts
Living Surfaces
The Nordic Copper range includes Nordic Standard ‘mill finish’ and Nordic Brown pre-oxidised copper, offering lighter or darker shades of brown determined by the thickness of the oxide layer. The extensive Nordic Blue, Nordic Green and Nordic Turquoise ranges have been developed with properties and colours based on the same brochantite mineralogy found in natural patinas all over the world. As well as the solid patina colours, ‘Living’ surfaces are available for each with other intensities of patina flecks revealing some of the dark oxidised background material.
Copper alloys are growing in popularity as well, including Nordic Bronze and Nordic Brass – which can also be supplied pre-weathered. The innovative Nordic Royal is an alloy of copper with aluminium and zinc, giving it a rich golden through-colour and making it very stable.
The surface retains its golden colour and simply loses some of its sheen over time, as the oxide layer thickens with exposure to the atmosphere to give a matt finish.
As well as for external applications, copper and its alloys are also the metals of choice for interior design, contributing a distinctive tactility to door furniture and handrails, and a visual richness to lighting and other fittings. But increasingly, they are being applied as high-quality finishes for walls, doors, ceilings, elevators and even staircases – as well as highlight surfaces, bars, splashbacks and counters – exploiting the materials’ unique performance characteristics.
Nordic Décor abraded and embossed mechanical surface treatments.
Nordic Décor offers real design freedom, adding a richness and opulence to public areas and homes alike.
Mechanically Applied Treatments
Most recently, various Nordic Décor copper surfaces and alloys have been made available with a diversity of mechanically applied surface treatments, adding an extra dimension. The latest developments in abraded and embossed mechanical surface treatments are particularly suited to interior design, adding another level of close-up visual richness, texture and tactility.
These treatments include embossing to provide regular patterns of raised or recessed forms, some also abraded to reveal highlights of the base material colour for additional design effects. Grindings are also available with linear, cross-hatched or curved-swirl hairlines to give distinctive matt surfaces. Nordic Decor surface treatments, combined with the natural living colours of copper and its alloys, offer real design freedom, adding a richness and opulence to public areas. They can provide an inherent warmth and sense of quality to highlight-surfaces in homes as well.
Designed by architects BIG, this museum has Nordic Brass transparent brise-soleil and perforated panel ceilings.
Copper cladding inside and out gives visual continuity. Photo: Ferguson Mann Architects
At this Sydney hotel, perforated and opaque Nordic Copper tiles – and their selective omission – curate views to the city and reduce glare. Photo: Katherine Lu
Forms and Systems
Apart from traditionally-jointed, rolled material, supported by a substrate, various other forms of copper are increasingly being explored by innovative designers. For example, copper can be supplied in profiled sheets or extremely flat honeycomb panels, and it can be pressed to provide surface textures and modulation. The material can also be perforated, expanded or woven as mesh giving varying degrees of transparency. When used internally, of course copper can be used in an even wider range of forms and systems, free from the constraints of weather-proof detailing.
One particular recurring architectural theme is material continuity, blurring the boundaries between outside and in with external copper cladding simply continuing past fully-glazed walls. When used outside, it’s important to remember that on-going changes to copper, including pre-oxidised and pre-patinated, and also alloys such as brass and bronze, will continue over time depending on the local environment. Again, this does not generally apply to interior applications and designers should understand and, indeed, celebrate the divergent developments of internal and external Nordic Copper.
The creative use of copper externally can have a major impact on interior spaces as well. For example, external screens of copper tiles arranged in chevron patterns add a distinctive art deco feel internally to a boutique hotel in Australia.