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Bland claims and hyperbole have tended to outweigh definitive statistics, creating understandable cynicism. However, among non-ferrous metals at least, information is available to compare performance of zinc, copper, aluminium and stainless steel building systems.

These reveal, for example, that 30 per cent of all zinc manufactured now uses recycled material while in Western Europe up to 90 per cent of rolled zinc recovered from roofs and rainwater systems (around 100,000 tonnes each year) is being recycled. To put this into perspective, this corresponds to between 1 and 2 million tons of ore reserves saved.

In terms of energy too, around 80 per cent less is needed when using reprocessed material than when using ore.

Though the UK may yet have some way to go to catch up, with the growth of zinc’s use for rainscreen cladding, roofing and a buoyant market for reclamation, sustainability should become an even more significant influence in its favour. However, we aren’t without our success stories as the recently refurbished Brighton Railway Station reclaimed zinc which had been in use for decades was and replaced it with material from the same manufacturer. For projects in which sustainability is a primary factor, energy consumption in zinc manufacturing is by far the lowest of metals used in construction today.

This is partly because it can be rolled at a lower temperature, but compared with copper and stainless steel zinc uses less than half the energy, and against aluminium less than a quarter. Maintaining an ecological equilibrium is of course essential for any naturally occurring material, but analysis of zinc concentrations in the Rhine, which passes through one of Europe’s areas of greatest industrial intensity, confirms that the balance is still well within acceptance tolerances.

Air emissions resulting from manufacturing are now as little as 0.05mg/m3 and water emissions 1.4mg/litre.

In addition to environmental factors, zinc’s specification owes much to design life performance, range of use, lasting appearance and the range of contemporary, weathered and the range of coloured finishes in which it is available.

In terms of practical considerations too, impact noise is far lower than that of more rigid alloys such as aluminium and steel. The new VM Zinc ‘Butyle’ solution provides a 10 dB acoustic gain, equivalent in human hearing to around a 50 per cent noise reduction.

Design life now routinely exceeds 50 years and as an alternative to cast iron or lead, zinc is also significantly lighter. A 2-metre length of 125mm wide half-round cast iron guttering typically weighs 8.3kg compared to zinc at only 2.75 kg. Zinc also lends itself to both traditional and contemporary design, whether new build or refurb.

Architects have commented how well the material blends with wood, stone and concrete while providing a contrast with the plethora of glazing finishes available. At 150N/mm2, it has a high tensile strength, while a melting point of 420°C provides resistance to surface spread of flame to Class 0 / Class 1. As an environmentally safe option to lead, its natural ageing process produces a similar patination and it provides enormous versatility in terms of shaping and forming. This makes it ideal for complex detailing with roofs such as that of Clapham Bandstand, which was formed of 62 sections.

For rainwater goods, although zinc is still relatively new to the UK, it undoubtedly fills a design void between inexpensive but visually uninspiring PVCu and more traditional, but expensive cast iron. Profiles are available to suit residential and commercial use and concealed brackets provide a distinctive appearance. Compared with cast iron, zinc guttering will not crack on impact, while even in coastal environments, corrosion resistance with pre-weathered finishes is better than aluminium. Zinc requires no particular protection because its naturally formed patina is self-protecting, and systems from manufacturers such as VM Zinc are manufactured using a patented pre-weathering process to produce an aged patination effect.

Products range from interlocking panel to standing seam roofing and rainscreen cladding systems, available in colours including sky blue, autumn brown and copper green. With bespoke detailing available, here at last is one section of construction in which design scope matches sustainability. Using what has become one of the fastest growing materials used in UK construction, designers have the option to combine aesthetics and performance with measurable effect on the environment. Zinc’s prominence in projects such as Grand Designs ‘Best Eco House’ in 2007, British Homes’’ ‘Small House of the Year 2007’ and Osborne Homes’ Demonstration House at the BRE is just the icing on the cake.