A soft building in France’s first ‘eco-quarter’
‘This is my first soft building,’ announces Édouard François of his latest housing scheme in Grenoble, as we pore over images and maquettes at his surprisingly low-key atelier in the 15th arrondissement of Paris.
The ambience is more workshop than office, with drawings, models and material samples jamming every available surface; evidence of countless architectural eureka moments that are tested, refined and finally brought into being. The latest eureka moment is softness.
François whips out an initial image of Grenoble showing three interlocking blocks clad in a black rubberised skin, like some kind of fetish accessory. ‘This is how I originally envisaged it,’ he explains, ‘but the client was a bit … ambivalent.’ Quelle surprise.
But for some time, François had been toying with the concept of energy efficient ‘soft architecture’, seeing a contradiction in buildings containing increasingly thick layers of ‘soft’ insulation concealed by a hard outer carapace of brick or concrete. ‘Why not express this softness more literally?’ he suggests.
This led to the notion of wrapping the building in a soft outer skin, which would have the effect of reducing both the thickness of insulation and the number of fixing points where cold bridging could occur.
François initially devised a prototypical installation sheathed in a cladding system resembling rubberized upholstery, and this led to the development of the thinner, cream coloured skin used on the Grenoble facades. In collaboration with roofing membrane manufacturer Sika Sarnafil, the new product took a year to develop and certify.
Made from polyolefin, a polymer more commonly used for shrinkwrap or moulded flexible foam, it is soft, waterproof and recyclable.
However as the skin was judged too potentially vulnerable to risk prolonged encounters with the public and sharp objects, each housing block sits on a rusticated base of concrete at street level, cast in swirling pastel-hued layers, with large pebbles embedded in their geological strata.
On the south-facing street facade, a giant Jenga-style timber pergola implanted with saplings provides deck access, shade and generous terraces for individual flats, so the general effect is as much rustic as erotic.
Blocks are animated by signature details, such as chestnut paling balustrades (typical of François’ penchant for cheap or disregarded materials) and living screens of greenery that beautifully and efficiently temper the summer heat.However the Grenoble scheme is not as luxuriantly extreme as the famous Flower Tower (AR September 2004), in which pots of mature bamboo formed a shaggy green corona around a Paris apartment block.
Known for its high-tech industries and as a base for winter sports (it hosted the 1968 Winter Olympics), Grenoble lies at the foot of the French Alps. You can’t escape the mountains; they cluster around the city like topographic bouncers and loom up at the end of every street, abruptly terminating vistas.
“Ecology for me is an artistic tendency”
The Grenoble housing development forms part of a wider zone d’aménagement concerté (ZAC), a now familiar urban development vehicle involving various architects working together within an overall planning framework.With the ZAC model there’s always a sense of many hands at work, and Grenoble’s ZAC de Bonne is no exception. Billed as France’s first ‘eco quarter’, it involves an ambitious parcelling up of former military land to the south-east of the city centre for new low-energy housing blocks, infrastructure and local amenities.
Plots are still being developed, so the area has a provisional, work-in-progress feel, but the southern sector along the Rue Andre Maginot is now complete and evolving into a more rooted and inhabited neighbourhood.
Lying at the eastern end of this street, François’ new building is one of the more lively extemporizations on the generic planning model of a mid-rise apartment block with a set-back upper storey.Blocks are arranged around central landscaped courtyards that define the scale of the new neighbourhood grid. François’ scheme is split between two blocks of social housing and one with apartments for sale.
Curiously, the private sector block is not clad in the unifying cream epidermis and makes do with plain grey render instead. ‘The client thought it might frighten off prospective buyers,’ says François, which seems a slightly dispiriting failure of nerve, though the grey facades do provide a hard masculine yang to the soft, creamy feminine yin.Inside, however, there are no such distinctions. Both apartment types have the same long thin plans, with dual orientation for views, light and natural ventilation.Compact planning keeps things tight and economical, but materials and detailing are handled with panache, turning a straightforward programme into something altogether richer and stranger.
The decks, terraces and facades are now also animated by the occupants and will evolve over time as the greenery grows and the materials weather and change. ‘I make living buildings,’ says François. ‘A building can lose everything over time. Time messes them up, as does the weather. We are in a world where people don’t maintain things. You have to accept that the building will have several faces.’
As the Grenoble ZAC attracted special financial backing from the EU, there was a remit to ensure that the development was also a test bed for new forms of energy conscious architecture, hence its designation as an ‘eco quarter’. ‘But most people took the money and did nothing,’ says François. ‘We thought we had a duty to be experimental.’ However François has little time for the earnest box-ticking of the ecological lobby, preferring a more cavalier approach that sifts and tests unorthodox ideas about form, materials, greenery and urbanism.
‘I have my own ecology, but it’s different from the political idea of what we would usually call ecology,’ he says. ‘Ecology for me is an artistic tendency. It’s a world, an obsession that has nothing to do with the proper way to empty your dustbin.’
Project: Housing Development in Grenoble
Architect: Édouard François
Location: Grenoble, France