Though less well known for standing seam systems than aluminium, zinc is now receiving widespread public attention as a consequence of projects featured in, for example, the 2007 Grand Designs Awards.
Growth in specification of zinc as a building product in the UK owes much to its lasting appearance, malleability and corrosion resistance.
It blends well with wood, stone and concrete and provides a contrast with the plethora of glazing finishes available.
As a roof covering it can be formed into the most complex shapes and used at pitches as low as 3deg.
Though less well known for standing seam systems than aluminium, zinc is now receiving widespread public attention as a consequence of projects featured in, for example, the 2007 Grand Designs Awards.
Bere Architects' 'Focus House' in the Finsbury Park area won 'Best Eco House', having used VM Zinc Plus in a Quartz-zinc finish with a concealed zinc rainwater system.
The system uses a patented pre-weathering process to produce a patinated appearance and texture which resembles aged material.
The finish requires no surface treatment or painting and is resistant to surface marking during installation.
Osborne Homes' Demonstration House built recently at the BRE, was designed as an entry in the 'GBP60K house' competition to demonstrate low cost, affordable, sustainable construction incorporating the latest thinking in waste reduction and energy efficiency.
Zinc was used for roofing, guttering and cladding in a structure that was built in a day and a half.
By complete contrast, for his design of Quarry House in Sevenoaks, Architect Steve Marshall of Munkenbeck and Marshall specified a combination of larch for the structural timber and zinc for the dramatic curved roof.
The silver grey larch will blend with the zinc's gradual, natural patination.
Like the timber, specified from an FSC accredited source, the zinc was chosen for its sustainability.
30% of all zinc manufactured now uses recycled material while in Western Europe, 90% of rolled zinc recovered from roofs and rainwater systems (around 100,000 tonnes each year) is now reclaimed.
There is already evidence of the knock-on effect in the UK; for the restoration of Brighton railway station the original zinc supplied by VM Zinc a century ago was removed, recycled and new material from the same manufacturer applied.
Recycling may owe much to the trend towards care of natural resources, but a high residual value of 60% to 75% of the current new material cost is, undeniably, drawing attention to its viability.
Energy used to manufacture, whether from ore or reclaimed material, is the lowest of the non-ferrous metals - less than half that of copper, and a quarter that of aluminium.
Even against the cost of manufacturing using recycled aluminium, zinc's energy consumption is around a third lower.
New technology affecting zinc manufacture now enables production of materials in a variety of finishes and colours.
In addition to Quartz-zinc, Anthra-zinc, a deeper charcoal colour, is produced for more contemporary architectural styling, while the newly launched Pigmento range offers the naturally grained texture of pre-weathered Quartz-zinc in blue, red and green.
Zinc's use in urban environments began to increase once risk of smog and acid rain-induced sulphur dioxide corrosion was eliminated following fossil fuel eradication.
This now means that the product's quoted design life invariably exceeds 50 years.
As an alternative to cast iron it is also significantly lighter and less expensive - a 2-metre length of 125mm wide half-round zinc gutter weighs only 2.75 kg compared to cast iron at over 8kg.
Although still relatively new as a guttering material in the UK, zinc is beginning to fill a void between inexpensive but visually uninspiring PVCu and more traditional but expensive cast iron.
Even in coastal environments, corrosion resistance is higher than that of aluminium and, unlike cast iron, it is not susceptible to impact cracking.
At 150N/mm2, tensile strength is high too, and resistance to surface spread of flame is to Class 0 / Class 1.
As an environmentally safe option to lead, zinc is now finding increasing use as an alternative to lead on heritage projects.
A 62-section cupola zinc roof and central finial, specified by Dannatt Johnson for the recently refurbished mid-19th century Clapham bandstand is a good example of a roof involving intricate detail.
Thought to be the biggest bandstand of its type remaining in the UK, it provides a vivid contrast to contemporary designs with standing seam roofs such as the Coptic Orthodox Church in Stevenage.
Maintaining an ecological equilibrium is essential for any naturally occurring material.
Analysis of zinc concentrations in the Rhine, however, confirms that the balance is still well within acceptance tolerances.
Emissions resulting from zinc manufacturing continue to reduce (down 43% between 1983 and 1995), while the diversity of uses for reclaimed product, which include galvanizing, zinc oxide and brass production, suggests that natural extraction will remain within manageable proportions.
With zinc use in the UK likely to be stimulated by the growing market for reclaimed and natural building materials, its future looks healthy in every respect.
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