The project list of Duncan Lewis and Hervé Potin has seen a marked shift from global to regional in recent months. Site-specific strategies developed in locations such as Fredrikstad on the southern coast of Norway, and Sokch'o on the Sea of Japan in South Korea (AJ 8.2.01), have begun to find favour in their home region of the Loire.
Achieving international recognition as a prerequisite for gaining domestic commissions is a familiar pattern in the career of many French designers, but the proliferation of Lewis-Potin interventions in the Loire has much greater potential than simply cultivating a local client base.
Rural settlement and land use in the Loire is characterised by a particularly active and primal relationship with geology. By reference to the traditions and continuing practices of stone, mineral and slate extraction, and the uncommon density of troglodyte dwellings in the region, Lewis has directed this first wave of local projects towards a confrontation with the geological substrata.
Lewis' design process is characterised by the wealth of visual and material evidence gathered in the period of site observation, and how those clues and traces are directly cannibalised to compose the new object.
Construction becomes more a question of reassembling the site, converting the existing terrain into what he terms a 'host landscape'. The architectural object becomes the hub of a set of transpositions which seek to bind landscape and structure together, physically and aesthetically.
As the Eden Project has demonstrated, the scarred industrial landscape is still not seen to have a value in itself. Even though thousands came to watch Grimshaw's structure taking shape in the former clay pit, that unique context was destined to be suppressed. Now grassy knolls, reminiscent of a service-station picnic zone, multiply there (as Lewis notes with disappointment).
All of the four Loire projects will include quasi-troglodyte buildings - a concept which the team has already started to bring to realisation for a school at Fredrikstad. The Loire has a particularly rich heritage of troglodyte dwellings, the best known being those cut into the river valley escarpments. Lewis explains that troglodyte solutions to habitation have particular thermal practicalities: they maintain a constant temperature of about 15-16C throughout the year.
At Louerre, in the Maine et Loire, the task in question is the construction of a lowbudget Maison de la Forêt - a multifunctional cultural and research centre, requested by the equivalent of the regional forestry commission.During negotiations with the client, the site for the building was shifted from an unpromising location in the centre of a ploughed field to the edge of woods.
This enabled a more diverse series of material transferences between the context and the new object to ensue, initially forming around the use of local wood for the facade. The troglodyte aspect was also an evolution of the initial brief, supported by reference to cave dwellings in nearby villages and to local traditions of stone extraction.
The work at Louerre will begin with a square-cut excavation into the rock strata beneath the edge of the wood. The first phase of refilling this extraction will involve the creation of a concrete staircase, which will eventually be the platform for an exhibition space. The building will emerge from the extraction at a shallow pitch.
This composition shares similarities with the Displaced/Replaced Mass series by Michael Heizer, one of the seminal works of late 1960s American Land Art, comprising a sequence of trench excavations with single stone masses tipped back into the negative volumes. There are also a number of direct conceptual alignments between Lewis' work and Heizer's desert excavations - his Double Negative in Nevada, for instance.
At Fredrikstad, in particular, the construction process follows a similar, reciprocal pattern between the extraction and placement of mass - a scouring and excavation of a granite core within the site; a geological event in miniature, blasting bodies of rock left proud by glacial recession and then assembling massive fragments as part of the fabric of the new buildings.
The main body of the Maison de la Forêt will not be directly cannibalised from the material of the extraction, but largely composed of materials representative of the nearby woodlands. The outer layer of all four facades will be made of finely cut strips of chestnut, spliced and put under tension with acacia wedges. The frequency and thickness of the wedges, and thus the permeability of the chestnut bands, will vary according to orientation. This extractioninsertion ensemble will thus, in essence, combine those two archetypal objects of rudimentary refuge: the cave and the wood cabin. (Potin also mentions that the cabin aspect references the agricultural vernacular forms of wood drying sheds. ) To either side of the building the rock strata will be sheared vertically and recesses created for storage, including locally produced sawdust fuel for a wood-burner heating system. The space beneath the projection of the main building will be fitted with greenhouse technology, and serve as a laboratory for visiting school groups.
Lewis' work gnaws at the logic which makes an antithesis of primitive assemblage and high design, rustic simplicity and urban sophistication - categories which Modernism only partly succeeded in eroding. In this sense we could look to Alexander Pope's grotto at his estate at Twickenham as an early-18th century precursor to Lewis' neotroglodyte programme. In Karen Lang's essay 'The Body in the Garden' (in Architecture, Landscape and Memory, Spon Press), Pope's grotto and shell temple is described as being a 'primitive' response to the abstractions of city life. Originally a link passage between Pope's villa and the landscape, it rapidly evolved into a multichambered place of reflection, a bejewelled and encrusted bunker retreat from his political and commercial career.
For Lewis, though, the engagement with geological substrata is already much more than an ironic gesture toward Primitivism, and is very much central to the commercial and sociological aims of his practice. A project in an abandoned quarry at Donges, in the Loire-Atlantique region, will be particularly significant in this respect.
The commission is for the office headquarters of the private, commercial enterprise, Charier. The company is involved in diverse environmentally related activities, such as waste management, mineral extraction and processing, and it owns a total of 14 quarries. Again, negotiations were necessary to convince the client to forego a conventional solution and to exploit the potentials of its own, rubblestrewn backyard. Despite the logical association of site and client, this is an important symbolic victory, as it amounts to a reversal of the received wisdom of public relations: the scarred landscape will become the seat of corporate identity.
The offices will occupy an intermediary tier in the terraced, south-west corner of the quarry, a position which will provide an open vista onto the Crossac marshes to the east. The shape of the main complex broadly repeats that of the corner of the quarry face behind it. But rather than simply running in parallel to that profile, it is pivoted into a truer alignment with the east, causing six of the 19 rooms of the forward section to converge and be buried, by varying degrees, into the rock.
Two are completely embedded and connected to the exterior by horizontal concrete shafts. While the office spaces remain in contact with the exterior and the main facade, the communal rooms - the restaurant and three conference rooms - form a secondary layer of genuine cave volumes, cut into the main body of the geological mass.
In a similar way to the assemblage of the Fredrikstad school, the Charier offices will be partly clad in the rock extracted for its interior spaces. The facade will, in fact, be a composite of real stone and concrete casts, made from polyester moulds of the quarry face. This is typical of Lewis' attitude towards materials: the real and the artificial are on an equal footing.
In what is potentially the team's most significant long-term project in the region - the creation of a Parc du Végétal at Angers - the relationship with the substrata begins with the aggravation of an existing, natural wound. There is a fault line and natural canyon in the Plateau de la Mayenne, north ofAngers, within which the park will comprise a 25ha strip. This fault line will be excavated to a width of 20-25m, and service and public facilities will not so much be built as interred. They will occupy recesses cut into the sides of the canyon, with their facades simply demarcated by the controlled exposure of the rock strata.
Other buildings will include graphicbearing, sunken greenhouse structures, integrated with a remodelled surface terrain and planted roofs. The greenhouse roofs will be inscribed or 'tattooed' with an image of a stretch of the Loire river, as seen in a satellite photograph, at a point where its characteristic islets and sedimentation banks are prevalent. The landscape's most active geographical force thus becomes crystallised as an image, as man declares himself a rival geomorphological agent to the forces of nature.
The team will also be responsible for integrating the park with the wider topography. It will be one element in the reclamation of a 150ha section of the plateau, which was previously the site of an aerodrome. Its demise saw the zone become an indeterminate no-man's-land, encroached upon by the spread of suburb industry, and crossed by major and minor road networks and the remains of a light railway. This effectively gives Lewis and Potin the opportunity to structure the northward expansion of their home town.
Two belts of vegetation will be established to either side of the park - a monumental framework through which to guide future patterns of land use. Broadly speaking, they will run parallel to the central fault-line canyon, but extend to the limits of the wider, wasteland territory - and beyond.
To the north-east, the vegetation will traverse a nature reserve at the base of the plateau escarpment, and then continue for a short distance into the landscape beyond the Mayenne River.
The park is intended to provide a focal point for the local horticultural industry, one of the mainstays of the economy of Angers, and will incorporate public attractions, research facilities, light industry and housing. The vegetation strips will act as unifying host environments for these diverse elements, effectively being vegetal sutures linking industry and leisure, natural and artificial habitats.
The reduction of the Loire to a satellitederived graphic, and the marking of the landscape with trans-topographical plantations, again recall the sort of manoeuvres that were performed under the name of Land Art. Explicit relationships are forged between technology, artifice and environment; the plateau will become the site where local, regional and global phenomena and forces are layered and allocated new roles.
Similar equations are at play for a project in the southern fringes of Tours, where work has begun on a water catchment station.
This competition was won with the help of a spectacular geological strata model, with a flat image of the proposed catchment earthformation as its surface layer. Lewis is restructuring the landscape according to the simple analogy of the concentric ripple formation of a raindrop entering a volume of water. As with the Loire graphic, an image of fluidity is processed into solid matter.
Only at Tours, the scale ratio is inverted: the scheme will involve the movement of some 90,000 tonnes of topsoil - a resource procured from the building sites of new housing projects in the same section of the Touraine suburbs.
But this work's inescapable analogy is with ancient tumuli or earthwork fortifications. In particular, Lewis cites Maiden Castle in Dorset. The station's northern flanks, where it borders the Cher river, will also reveal a structural kinship with tumulus formations, in that stone embankments will emerge from the earth folds. These are the outer walls of a tunnel cavity within the earthwork, which will serve as an exhibition space.
From the exterior, the exposed stone layer also has a representational function. It is meant to be perceived as a surface emergence of the hidden geological strata, the rim of the vast subterranean vessel of permeable and semi-permeable rock. Topiary and willow plantations will be 'moulded' to mimic the folds of the 9-10m-high embankments and create vegetal tunnels.
The resurrection of the troglodyte impulse implies an atavistic journey back into the origins of architecture, and the birth of the contradistinction between the built object and the landscape formation.
Lewis and Potin are undoubtedly retracing certain pre-urban cultural ties with environmental context.
But the true significance of their work lies in the fact that this return is not made under the auspices of a marginal, alternative ideology, but is the result of a complete embracing of technological advancement toward the refinement of the expression of site.
Through the agility of their design process, the scarred industrial landscape becomes a field of endless possibilities - a ready-made geological laboratory which should be mined further in the name of a radical aesthetic, not suppressed by the bland cosmetics of the landscape norm.
Lewis and Potin's major foreign projects have so far been located on coastal fringes.The latest evolution of this theme involves the coast of the peninsula of the State of Qatar in the Persian Gulf.
Working with the Science Centre, Paris, and the Nantes-based design group Bloc, they are preparing a section of the eastern coastal strip for diverse development - including wind farms and, potentially, a small port and an offshore marine research facility.
Based on the appearance of weathered, archaeological remains in the desert, they propose to inscribe the zone with an Islamic pattern, made from concrete inserts formed from the sand they will displace. The drawings even see the pattern (taken from the 16th-century tomb of Sultan El Ghoury) continuing beneath the shallow coastal waters.
This process has the vital function of stabilising the coast prior to development, but will also turn the zone into a vast earthwork tattoo, visible from aircraft operating at Doha airport.
MAISON DE LA FORÊT, LOUERRE ARCHITECT: Duncan Lewis and Hervé Potin
COLLABORATORS: Tanguy Vermet, Thierry Maitre
LANDSCAPE ARCHITECT: Stéphanie Laurent
SCENOGRAPHER: Lucie Lom (MarcAntoine Mathieu and Philippe Leduc)
WOOD ENGINEER: CNDB (Jean-Yves Riaux)
AMÉNAGEMENT D'UNE STATION DE CAPTAGE, TOURS ARCHITECT: Duncan Lewis and Hervé Potin
LANDSCAPE ARCHITECT: Stéphanie Laurent
COLLABORATORS: Chadi El Chami, Tanguy Vermet, Thierry Maître, Benôit Rougelot
PARC VÉGÉTAL, ANGERS ARCHITECT: Duncan Lewis and Hervé Potin, with Denis Brillet, Benoît Fillon, Stéphane Lagré, Pascal Riffaud, architects
COLLABORATORS: Tanguy Vermet, Thierry Maître, Chadi el Chami
SIÈGE SOCIAL 'CHARIER', DONGES ARCHITECTS: Duncan Lewis and Hervé Potin, with Anne-Flore Guinée, architect
KVERNHUSET UNGDOMSSKOLE, FREDRIKSTAD ARCHITECT: Duncan Lewis associated with Pir II arkitektkontor AS (Ogmund Sorli, Mette Melandso)