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EDITORIAL
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COPPER ARCHITECTURE DRIVEN BY DESIGNERS In this issue, we focus on some of the fresh opportunities in contemporary design being explored by architects, taking copper and its alloys beyond the numerous established surfaces, forms and installation systems available today. Our first article considers an architect’s own office (pages 4-7), defined by an innovative three-dimensional brass surface modelled using hydroforming techniques, and how its appearance has begun to evolve over time. Then, we see how the scale-like bark of plane trees surrounding new additions to a museum (pages 8-13) are reflected in the design of bespoke, bronze shingle cladding that gently complements the adjoining church and gardens. Although using traditional standing seam techniques, the faceted golden copper alloy facades of our next project – a sports complex (pages 14-17) – are thoroughly modern and fragment the building’s box form. Our central feature explores new museum additions to the iconic Paris Mint (pages 18-21), characterised by a transparent skin of perforated copper panels almost suggesting that coins have been stamped from it. Moving on, impeccably crafted detailing on a modest-sized pavilion (pages 22-25) creates a golden gem. Here, the architects’ deceptively simple concept extends golden copper alloy facade cassettes over the almost-flat roof, with crisp edges throughout.
Also defined by an exemplary approach to detailing is a new headquarters building (pages 26-27) in exposed concrete topped by a dramatic ‘box’ clad entirely in green prepatinated copper. As we have seen in this and previous issues, the golden alloy of copper with aluminium and zinc continues to be popular for all kinds of projects. But the architects for a major redevelopment (pages 28-31) within a World Heritage Site wanted a much quicker transition from the initially reflective golden surface to a matt hue – achieved with a bespoke, factory-applied brushed finish. Our last project is an organic form (pages 32-33), enticing customers into the café that it envelops, executed with 18th century copper sheathing techniques enabled by computeraided design. We end with an important update on the environmental performance of architectural copper (pages 34-35) and how to approach environmental rating systems. We hope you enjoy this issue. The Editorial Team
Order your free printed copy and read magazine back issues on copperconcept.org Copper Architecture Forum 44, May 2018
Publisher: Nigel Cotton, ECI Editor in Chief: Robert Pintér
Copper Architecture Forum is part of the ”European Copper In Architecture Campaign”. It is published twice a year and has a circulation of 25.000 copies.
Editor: Chris Hodson RIBA
The magazine is distributed to architects and building professionals throughout Europe – and beyond – in English, Czech, French, German, Hungarian, Italian, Polish, Russian and Spanish languages.
Editorial panel: Birgit Schmitz, De Kazimierz Zakrzewski, Pl Marco Crespi, It Nicholas Hay, UK Nikolaos Vergopoulos, Gr Nuno Diaz, Es Olivier Tissot, Fr Pia Voutilainen, Se, No, Fi, Dk Robert Pintér, Hu, Cz, Svk, Ru Yolande Pianet, Benelux
E-mail: editorialteam@copperconcept.org Address: CAF, European Copper Institute, Avenue de Tervueren 168 b-10, B-1150 Brussels, Belgium Layout and technical production: ECI Printing: Copy & Consulting Kft., Hungary
Editorial team: Ari Lammikko, Chris Hodson, Graeme Bell, Herbert Mock, Hermann Kersting, Robert Pinter birgit.schmitz@copperalliance.de kazimierz.zakrzewski@copperalliance.pl marco.crespi@copperalliance.it nick.hay@copperalliance.org.uk nick.vergopoulos@copperalliance.gr nuno.diaz@copperalliance.es olivier.tissot@copperalliance.fr pia.voutilainen@copperalliance.se robert.pinter@copperalliance.hu yolande.pianet@copperalliance.eu
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CONTENTS
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32 – 33
18 – 21 COVER: Paris Mint
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Photo: front - Benjamin Chelly back - Aitor Ortiz
2 COPPER ARCHITECTURE DRIVEN BY DESIGNERS – editorial comment
22 – 25 COPPER ALLOY ON THE EDGE – a pristine golden copper alloy pavilion sits at the heart of a new residential quarter for Munich
4 – 7 REEDED BRASS – a modular office building in Graz, Austria, with an innovative three-dimensional ‘reeded’ brass external skin
26 – 27 COPPER AND CONCRETE MIX – this new company headquarters in Bavaria makes a bold statement with an offset green copper box on top
8 – 13 TIMELESS BRONZE – bronze-clad interventions to the Garden Musem on one of London’s most historic and challenging sites exude a timeless quality
28 – 31 COMPLETING THE SQUARE – copper alloy fins with a bespoke brushed finish play a key role in a redevelopment to complete one of Edinburgh’s historic squares
14 – 17 SPORTING GOLD – this new sports complex near Marseilles is clad in a golden copper alloy to elevate the importance of sport in the community
32 – 33 COPPER & COFFEE – conceived as the mouth of an orchid, this copper roofed café creates a strong sculptural presence in a challenging London location
18 – 21 DYNAMIC METALMORPHOSIS – contemporary, copper-clad interventions reference the historic role of the Monnaie de Paris, the world’s oldest continuously running mint
34 – 35 Architectural Copper And Environmental Performance – updating performance characteristics, production, recycling and continuing improvement, as well as how to use environmental ratings
© Copper Architecture Forum 2018 COPPERCONCEPT.ORG 3
REEDED BRASS
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by Chris Hodson
Photo: Viereck Architekten ZT - GmbH
This modular office building in Graz, Austria, is defined by an innovative three-dimensional ‘reeded’ brass external skin. Viereck Architekten’s [BOX:09] concept uses standardised, prefabricated, fully-finished modules to create open-plan spaces for living or working. The individual modular units, which are about 20m2, are factory-built complete with walls, roof and floors, as well as all finishes and services in place. On site, modules are simply locked together with turnbuckles, very quickly forming the required building. This example – the architect’s own office raised above car parking – makes the most of a particularly restrictive site.
HYDROFORMED PANELS Central to the building’s architecture are the facades made up of brass panels with a distinctive, three-dimensional reeded surface pattern. The panels were manufactured by a specialist company using hydroforming techniques that optimise the malleability of copper and its alloys. Here, brass sheets are formed by high pressure hydraulic fluid working the metal into a die or mould, manufactured specially for the specific design. This process enables complex three-dimensional patterns to be replicated accurately and repeated. Each 175 x 65cm panel was then glued to the substructure as part of the module fabrication, using a special system to guarantee performance and long-life durability.
Architects: Viereck Architekten Copper Product: TECU® Brass wave
Photo: Wolfgang Croce
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2009 Photo: Andreas Tischler
THE EVOLVING FACE OF COPPER AND ITS ALLOYS IN ARCHITECTURE The natural development of patina is one of copper’s unique characteristics. When exposed to the outside atmosphere it protects itself by developing a patina layer over time which makes it weather resistant with a lifespan over many generations. The visual appearance of copper and its alloys – such as brass – is largely influenced by the way the protective patina forms, its thickness and composition. Scientific results confirm that the level and how rapidly the surface appearance change depend primarily on: •
•
• •
air quality & weather conditions: the concentration of air pollutants, deposition of particles and prevailing weather conditions largely influence the patina composition distance from the sea: materials close to marine splash areas will develop a green hue quite quickly, whereas materials placed in urban environments may tend towards a dark brown hue alloy composition surface inclination and orientation.
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Changes are very gradual and not entirely predictable – just like the weather, which, in turn, is responsible for copper’s continual changes. The prevailing concentrations of air pollution and the environmental conditions essentially determine the composition and protective properties of the patina. The interaction of the patina with the local atmospheric conditions will determine the surface appearance and how it changes over time.
Copper
Within a few days of exposure to the atmosphere, the surface begins to oxidise changing its colour to chestnut brown which gradually darkens over several years and later may become a typical green patina.
Bronze
An alloy of copper and tin, the original warm reddish-brown surface of bronze develops in a distinctive manner through weathering. A brown-red surface oxidation with a brown-grey undertone is typical for this alloy. The material then gradually changes to dark brown anthracite throughout and the subsequent green patina coating forms much more slowly than with pure copper.
2012 Photo: Angelo Kaunat
Golden Copper Alloy
This golden material is an alloy of copper with aluminium and zinc, which is very stable. It behaves differently to pure copper in the environment as it has a thin protective oxide layer containing all three alloy elements when produced. As a result, the surface retains its golden colour indefinitely and simply loses some of its sheen as the oxide layer thickens with exposure to the elements, giving a matt gold coloured appearance.
Brass
Brass is an alloy of copper and zinc, initially with a distinctive, golden yellow colour. When exposed to the atmosphere the surface begins to darken within weeks and can change to a dark brown, sometimes in only a year. The initially shiny surface also changes to a matt finish.Generally, older vertical brass surfaces will remain dark brown, although a blue/ green patina can eventually develop on roofs or other areas where rainwater dwells longer. The photographs shown above, taken some 3 years apart, provide a demonstration of the visual changes that occur with brass in the environment over time. This process was explored in more detail on another project in our 42/2017 issue (pages 34-37).
SURFACE EVOLUTION
SURFACE EVOLUTION ON COPPER CONCEPT To discover more project examples and information on surface evolution over time of copper and its alloys go to copperconcept. org/en/references and turn on “surface evolution” filter or scan QR code. A brochure on this topic is also available at copperconcept.org/en/publications
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TIMELESS BRONZE 8 COPPER ARCHITECTURE FORUM 44/2018
Photo: David Grandorge
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Bronze-clad interventions expanding a museum on one of London’s most historically important and challenging sites exude a timeless quality – despite using modern, lightweight construction techniques. Dow Jones Architects discuss their design. The Garden Museum overlooks the River Thames and the Houses of Parliament beyond, and adjoins Lambeth Palace - for nearly 800 years the London residence of the Archbishop of Canterbury, the head of the Church of England. It celebrates the history, culture and design of gardens and is housed in the deconsecrated, protected church of St Mary at Lambeth.
Dow Jones Architects
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Our first phase of work in 2008 involved a two-storey gallery inside the church, creating new galleries, an education room and storage, and consolidated the nave as an events space. This allowed the museum’s many varied events and educational activities to flourish, and generated a 400% growth in visitor numbers in the first year.
DRAMATIC URBAN PRESENCE
The pavilions provide rooms for learning and community activities and a café, connected by a glazed cloister that frames a new, Dan Pearson designed garden. Offices, workshops and other support areas fill a gap between the church and garden wall. The site presented many challenges including protected trees, historic tombs and views to Lambeth Palace – as well as some 36,000 bodies in the old cemetery. Our solution is a lightweight, bronze-clad timber structure built on a thin 300mm concrete raft.
WESTMINSTER BRIDGE HOUSES OF PARLIAMENT RIVER THAMES
The 2013 competition-winning second phase extends the museum both within the existing building and out into the churchyard. Being housed in a church building, the museum was often mistaken for part of the neighbouring Lambeth Palace. Our new building provides a much-needed, dramatic urban presence – a cluster of bronze-clad, timber frame pavilions fronting the street.
LAMBETH BRIDGE
LAMBETH PALACE
GARDEN MUSEUM
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COPPER IN DETAIL
Warm roof construction: - Green roof construction over ply deck - Rigid board insulation - Breather membrane - 18mm WBP ply deck - Firrings - 150mm joist zone - Internal finishes on suspended MF ceiling
Warm roof construction: - Bronze cladding with flat seams - Breather membrane - 25mm ply - Rigid board insulation - Vacuum panel insulation - Vapour control layer - 18mm WBP ply deck - Firrings - 150mm joist zone - Internal finishes on suspended MF ceiling
Bronze coping to match rain screen. Drip detail to be advised by specialist subcontractor
Wall construction: - Bronze shingle cladding - Breather membrane - 18mm WBP ply - 50mm vented zone formed with treated softwood battens - Breather membrane - 18mm WBP ply - 150mm timber stud construction infilled with rigid board insulation - 25mm rigid board insulation - Vapor control layer - 12mm Ply - 12.5mm Plasterboard with skim finish
BESPOKE BRONZE SHINGLES The pavilions are clad in bespoke bronze shingles set out to reflect the scale-like quality of the bark of the surrounding plane trees. Plane trees were introduced to Britain by royal plant-gatherer John Tradescant, who is buried in the churchyard and is the genesis of the museum. A full-scale mock-up of the facade was built on site to explore different cladding material options of bronze, brass and preoxidised copper. Bronze was chosen as it will weather from a bright copper to an earthy chocolate brown. This colour will allow the building to sit quietly within the graveyard, allowing the garden and church to have the strongest presence. Some flat roofs are also bronze-covered, alongside planted ‘green roofs’.
Architects: Dow Jones Architects Copper Installer: Richardson Roofing Copper Product: Nordic Bronze Photos: Anthony Colemen - unless indicated otherwise
Bronze clad fascia panel
The interlocking bronze shingles are 950 x 450mm, spaced 150mm apart horizontally, have concealed fixings and are folded at the edges for strength. They were formed on site and fixed to resilient marine plywood, with separating breather membrane in between. This was backed by a 50mm battened vent zone before another layer of marine ply mounted on the insulated timber stud frame of the building. Bronze shingles were used internally in some areas as well. The shingles wrap tightly around the façade, meeting the windows and slim warm roof construction to form a crisp outline. Mechanical extract vents were integrated into the cladding shingles by creating custom bronze cowls which protrude outwards.
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SPORTING GOLD
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golden copper alloy - a beautiful, solid, perennial weathering material, that knows how to age with nobility
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by Chris Hodson
PLAYFUL AND DYNAMIC
The faceted golden copper alloy facades of this new sports complex in la Fare les Oliviers, near Marseilles, fragment its rectangular box form. They also help realise the architects’ ambition to enhance the cultural importance of the gymnasium and sport within the community, established by the ancient Greeks and Romans.
Atelier Montecristo’s design optimizes the 4 metre fall along the sloping site to maintain a relatively consistent roof line. The taller main sports areas are set down into the hillside, level with a football stadium, while reception areas at a higher floor level align with the site entrance. All the facades and areas of roof are clad in an alloy of copper – with aluminium and zinc, giving it a rich golden colour – using traditional standing seam techniques, on a timber frame. The copper alloy was chosen for its durability and sustainability, acknowledged by the architects as: “a beautiful, solid, perennial weathering material, that knows how to age with nobility.” The architectural treatment of the facades is playful and dynamic, reflecting the outline of surrounding hills. The long east and west facades are simple large planes, folded vertically. But the east facade also welcomes visitors with a sequence of ‘sporting giants’, cut out of lacquered steel sheets, fronting a glazed horizontal band. Only the south facade reveals the complete building height, with a gem-like series of triangular copper alloy surfaces, on a timber ‘trellis’ framework, subverting the building form.
Architects: Atelier MONTECRISTO and Fabrice Giraud Architecte DPLG Copper Installer: Dautremer – Gap Copper Product: TECU® Gold Photos: Florent Joliot
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DYNAMIC METALMORPHOSIS
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DYNAMIC FACADE
by Chris Hodson A major presence on the Left Bank of the Seine, the Hôtel de la Monnaie is a prime example of 18th century neoclassicism. A recent, major renovation project includes contemporary copper-clad interventions, referencing the building’s historic role as the home of the Monnaie de Paris (Paris Mint) – the world’s oldest continuously running mint. Designed by Jacques-Denis Antoine, the original building successfully combined a grand palace of massive, heavilyrusticated stone with, in effect, a factory. It wraps around a grand Inner courtyard with subsidiary courts alongside and is terminated at the rear by a diagonal street pattern.
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The 5-year renovation project, known as ‘Méta(l)morphoses’, addresses the site’s isolation, particularly at the rear, enabling its rediscovery by the public and encouraging access to the Mint’s museum, the Musée du Conti. It also rehouses the specialist crafts that have been practised at the Mint since its creation but in a modern environment.
Architects: Atelier d’architecture Philippe Prost Copper Installer: BAUDIN Chateauneuf Copper Product: natural copper Photos: Philippe Prost, architecte / AAPP © adagp – 2017 © Aitor ORTIZ
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OK EVOCATIVE MATERIAL The project’s designers Atelier d’architecture Philippe Prost sought a contemporary architecture for the new interventions that would resonate with the neoclassical stone original and create a dialogue. It seemed obvious to them to make metal the raw material of the project – a living architecture reflecting the materials used in the Mint’s crafts and evoking its special expertise. In particular, they wanted the Mint’s long history of recycling coins reinforced by the idea of a perennial and renewable copper envelope for walls and roofs. So, it is perhaps no surprise that the copper panels covering the new facades almost look as though coins have been stamped from them. The regular pattern of circular perforations provides transparency, as well shading to windows which can be modified by openable copper shutters.
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COPPER ALLOY ON THE EDGE
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by Chris Hodson Beautifully detailed and executed, a pristine golden copper alloy pavilion designed by Maisch Wolf Architekten sits at the heart of Baumkirchen Mitte, a new residential quarter for Munich.
Part of the regeneration of the site of a former railway repair works, a medium-rise block of apartments separates the new quarter and its public open spaces from a busy railway line. The north elevation is treated as an acoustic barrier to the railway, while the south frontages open up with a regular rhythm of private gardens and balconies, and are topped by roof terraces.
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COPPER IN DETAIL
A GOLDEN GEM Conceived as a golden gem, all the facets of the pavilion’s exterior are covered by rhomboidal copper alloy cassettes with concealed joints and fixings to provide flat surfaces. They are set out on a diagonal grid that continues around corners with a deceptive simplicity. Similarly, edges around glazed openings are crisp, clean and apparently devoid of coverstrips, flashings, or other additions – the result of clever detailing and expert installation.
The meandering apartment block enwraps an open landscaped area and also the multi-purpose pavilion at the heart of the community. The golden pavilion, with its irregular pentagonal plan form, is overlooked by every apartment – and from all angles, including from above. The careful design and detailing of its facades and roof, all clad in an alloy of copper, were therefore critical to its success.
For example, conventional window cills have been replaced by a clean edge to the copper-alloy cladding concealing a small gutter to remove rainwater. While the rhomboidal cassettes provide water-proof facades, on the almost-flat roof they sit over a waterproof membrane with concealed edge gutters, internal down-pipes and external overflow for water management. Introducing three roof-lights, each a different design, proved particularly challenging.
LATERAL ROOF SECTION
COPPER ALLOY RHOMBOIDAL CASSETTE OVER-ROOF
SEALED SUPPORT BITUMENOUS MEMBRANE SEALED UNDER-ROOF
COPPER ALLOY RHOMBOIDAL CASSETTE VENTILATED FACADE
Mike Fleischer/Maisch Wolf Architekten
Architects: MAISCH WOLF ARCHITEKTEN Copper Installer: FLEISCHER Metallfaszinationen Copper Product: TECU® Gold Photos: Ralf Dieter Bischoff – Fotografie
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COPPER AND CONCRETE MIX by Chris Hodson A new company headquarters in Ingolstadt, Bavaria, makes a bold statement with an offset, green copper box on top.
Architects: Eßmann, Gärtner, Nieper, Architekten Copper Installer: Karl Wild Copper Product: TECU® Patina Photo: Ralf Heidenreich Fotografie
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Designed by Eßmann, Gärtner, Nieper, Architekten, the new building for construction industry mixing equipment specialist Collomix is on three levels plus an underground car park. The first two levels are built of exposed concrete, with large windows and a double-height entrance area, creating a calm commercial presence. This contrasts with the dramatic ‘box’ – clad entirely in green pre-patinated copper punctuated by vertical windows – which sits independently on top, overhanging and sheltering the main entrance. At either end, the box opens up to provide white-framed balcony areas with extensive glazing beyond.
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COMPLETING THE SQUARE
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Hoskins Architects and CDA discuss the role of copper alloy fins with a bespoke brushed finish in defining a major redevelopment to complete one of Edinburgh’s historic squares. ST ANDREW SQUARE
3-8 ST ANDREW SQ
SOUTH ST ANDREW ST
ROSE STREET
SOUTH ST DAVID ST
GEORGE STREET
St Andrew Square sits in the heart of Edinburgh’s ‘New Town’ World Heritage Site, at the eastern end of George Street, and a counterpoint to Charlotte Square at the west end. But unlike Charlotte Square, which is a virtually intact set-piece of Georgian architecture, St Andrew Square provides a more heterogeneous context with a wide range of Victorian, mid20th century and early 21st century buildings. In many ways, then, a more permissive context than much of the World Heritage Site but, importantly, also one with little consistency in materials, height, massing, architectural language or street-level conditions. Hoskins Architects and CDA investigated options for the redevelopment of a majority of the southern edge of the square, consisting of a handful of buildings – numbers 3 to 8 – of varying periods and quality.
PRINCES STREET
Architects: Hoskins Architects and Comprehensive Design Architects (CDA) Copper Installer: Charles Henshaw & Sons Copper Product: Brushed Nordic Royal Photos: dapple photography
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The buildings had been interconnected as a company headquarters, extended and altered over a number of years, leaving a piecemeal, ad hoc assemblage of spaces when vacated. Initial studies from 2007, proposing retention of a number of existing buildings, proved to be commercially unfeasible and, following a change of ownership in 2013, designs were revised to incorporate further demolition. The final scheme comprises 9,300m2 ‘Grade A’ office space, 6,500m2 leisure/retail and a suite of luxury apartments.
OPEN AND SOLID The massing strategy of projections and recesses reflects the scale of the historic plots on this side of the square, reconciling a historic grain with the contemporary demands of large-floorplate, open-plan office accommodation. The pursuit of an architecture that reveals and conceals as pedestrians move in relation to it was important to us, as was moving beyond the ‘dumb glass box’ of speculative office development. A series of metal and stone fins enables the complex to be very ‘open’ when viewed directly (taking advantage of extraordinary long views and maximising daylight), whilst appearing solid in oblique pedestrian views (in keeping with its Georgian and Victorian sandstone neighbours).
BRUSHED COPPER ALLOY For the fins, Hoskins Architects and CDA appraised various metals and identified a group of copper alloys for long-term quality and handsome weathering. Finally, they settled on a golden alloy of copper with aluminium and zinc, giving a rich golden throughcolour that is very stable. Unlike bronze or brass, this alloy’s surface retains its golden colour and gradually loses some of its sheen as the oxide layer thickens with exposure to the atmosphere, resulting in a protective matt finish. However, the architects wanted a much quicker transition – from the initially reflective golden surface to a relatively matt golden hue – than happens naturally in the environment. This was achieved with bespoke surface treatment of the copper alloy in the factory using a belt sander. Various grades of grit were tested until a non-reflective, brushed surface was produced. The brushed copper alloy will now change in more subtle ways over time.
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COPPER & COFFEE Conceived as the mouth of an orchid, this copperroofed café creates a strong sculptural presence in a challenging location, as its designers Mizzi Studio explain. The Colicci Coffee kiosk at Westfield Stratford City Shopping Centre sits at the entrance of London’s largest mall and at the apex of the main street linking Stratford Station with the nearby Olympic Park, including its Copper Box Arena, and iconic buildings such as Zaha Hadid’s Aquatic Centre. Responding to this environment, the kiosk’s tour-de-force is a swelling copper roof which seemingly floats above its glass walls, offering protection from all weathers. Designed to mimic the mouth of an orchid, the entrance and roof are shaped to lure visitors in to a copper cocoon, converting the usual ‘grab-and- go’ coffee culture into a sensory, warm user experience.
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ANCIENT AND MODERN TECHNIQUES The roof’s surface is a combination of an 18th century copper sheathing technique and computer-aided design. We developed a digital skin which reflected the eventual physical structure of the roof, then divided its surface area into virtual tile segments – each translating into CNC-cut sheets which could be manually clad. The result was a bespoke jigsaw of 542 individual numbered copper pieces, assembled by hand with a pneumatic gun and 20,000 rivets to form the sculptural mass. Patinated fingerprints and hammer marks were left to showcase an earthy texture as viewers move closer to the structure. The copper has been sealed with a matt, clear lacquer to preserve the material’s textural history and retain its rich lustre and reflectivity.
Architects: Mizzi Studio Copper Product: natural copper Photos: Greg Fonne
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GREEN BUILDING
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Copper can be recycled again and again without any loss of performance or qualities
Architectural Copper and Environmental Performance by Nigel D R Cotton, Program Director, European Copper Institute Before assessing the environmental benefits of architectural copper, it’s worth going back to basics. Copper is a natural element within the earth’s crust which has been incorporated into living organisms throughout the evolutionary process. It is an essential nutrient required by virtually all higher life forms and nature is well adapted to making best use of copper, protecting itself from any negative effects. This applies at the most basic levels right up to the most complex metabolic functions of the human body. It also holds true with the long-term effects of copper on buildings. Copper facades, roofs and other external architectural elements develop a protective patina over time which can reform if damaged. This ensures extreme durability and resistance to corrosion in virtually any atmospheric conditions and, unlike some other architectural metals, copper does not suffer from underside corrosion. Consequently, it is invariably the supporting substrate or structure that eventually fails rather than the copper itself. In fact, copper roofs have been known to perform well for over 700 years.
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Performance Characteristics Copper is generally applied as a lightweight covering, requiring less supporting structure than many materials. With a low thermal expansion value, movements due to temperature changes are minimised and designed-for, avoiding deterioration and failure. In addition, the high melting point of copper ensures that it will not ‘creep’ or stretch as some other metals do. Copper is also classified as A1 (non-combustible material) in accordance with EN 135011:2007+A1:2009. It is safe to use and can be worked at any temperature, without becoming brittle in cold weather or deforming in hot weather. It requires no decoration, maintenance or cleaning, saving resources, cleaning chemicals and cost. Copper sheets’ (copper massive) interaction with the environment has been assessed under the European Reach chemical policy and has no classification/restriction.
Photo: Esko Tuomisto
Photo: Sigurgeir Sigurjónsson
Production and Recycling
Continuing Improvement
European copper products for architectural applications are produced to EN 1172 specifications in world class plants with strictly monitored environmental performance and well-established recycling routes. They include high levels of recycled materials – typically 85% or more with scope up to 100%, saving on energy and greenhouse gases, and contributing to the circular economy.
The recycling of copper is a well-established practice and its extent follows overall consumption patterns. This is due to the relative ease, compared with other metals, of re-using both processing waste and salvaged scrap from eventual demolition, as well as the incentive of copper’s value. Copper can be recycled again and again without any loss of performance or qualities.
Copper occurs naturally as part of the cycle of metals which form in nature, being used by society and returning to nature or being recycled for further use by society. The economic value of copper drives recovery and recycling, not just of copper but also many other materials during dismantling and demolition.
The copper industry – from mining to fabrication – spends in the region of 30% of capital expenditure on improving environmental performance. The processing of copper is on a ‘Continuous Improvement Program’ to service customers and shareholders, and comply with current market and policy needs. The industry is responding to the European Commission ‘circular economy’ initiative and looks forward to receiving more scrap for re-use as the economy becomes more efficient at managing material use throughout its life, especially towards end-of-life.
Environmental ratings Environmental rating tools are important for investment decisions and useful for looking at the whole supply chain and determining where the greatest improvements in environmental performance can be made for a given product. Unfortunately, they have many inadequacies when used to make comparisons. For comparisons to be worthwhile, accuracy of the tool and the methodology behind it need to be both robust and fair when comparing two products of very different compositions and implementations, even if for the same use. For simplification, too many tools have used non-robust and unfair assumptions, resulting in extremely misleading comparisons. Easy mistakes to make include:
• • • •
comparing energy and cost per tonne rather than per m2 of material, thus misrepresenting thinner, lighter materials such as copper missing the cost and environmental benefits for complete construction of lightweight materials using inappropriate life span estimates, thus adding ‘energy use’ for unnecessary replacement disregarding today’s efficient recycling practices.
Today, we urge architects to focus their comparisons on: Primary Energy; Ozone depletion potential; Acidification potential; Eutrophication potential; and Photochemical Ozone Creation potential. These are impact categories that are wellknown, global and mature – rather than other lesser known, non-robust and erroneous comparative indicators, especially in the field of toxicity, land use and resource use.
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Copper Architecture Forum
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