Interview with Dominique Marrec, architect ECDM agency
The RATP administrative centre in Thiais is responsible for the traffic management of 300 buses and provision of 24-hour facilities for 800 drivers. Located in an industrial zone on the outskirts of Paris, this award-winning project, designed by agency ECDM, is an ode to the qualities of minerals. Mirroring the variety of coatings within the bus depot, a double skin first follows and then lifts the pavement. The result is a non-directive setting in which users are free to determine what they want to conceal and what they want to leave open to view.
What is the thinking behind this highly "graphic" building?
We wanted to focus on the mineral nature of the site and propose a building that acts as a continuation of the ground surface and emerges like a deformation of that surface. It was this approach that gave us the idea of a skin that would blur distinctions between traffic flows and building while giving the site a strong visual identity. Two implementation techniques come together here: heavy prefabrication and siding, as the 3cm thick skin provides a pavement that is partly open to traffic and rises up, sweeping away any thickness, to lose itself in the sky. The Lego-like framework we devised, as well as offering anti-slip properties, gives colour-stippling effects that break up the play of lights and mirrors from the tinted external exterior bonded glass bays. This skin uses Ductal® not only for its structural properties but also for its visual aspect, its depth of colour and quality of finish. The marriage of this project concept with the performances of the chosen material enabled us to offer users maximum freedom of choice in their use of the space available. There was no predetermined plan for the interior layout. Instead, it was tailored to their aspirations and subsequently we came along to cut out the skin, virtually with a box-knife, to create the openings, patio and access points.
We used Ductal® not only for its structural properties but also for its visual aspect, its depth of colour and quality of finish.
Just like the Ductal®/bonded glass facades, this project is made up of a multitude of technical details that create its overall purity of line. What were the keys to this success?
The project is really founded on the commitment of all concerned: Philippe Isembeck of RATP, Vincent Souyri of SEDP, Dominique Stoeux of Betsinor and Léopold Lombard and Mouloud Behloul at Lafarge. As a result of all their work, we were able to come up with the unusual and innovative implementations, throughout the process of researching the project. While the Ductal® skin provided a certain number of solutions to the problems raised by our choices, it was really because all concerned put their energies into the studies, constructing prototypes, carrying out tests, creating the moulds that would respond as fully as possible to the imperatives imposed on us by our own demanding standards of rigour and efficient use of resources.
More about RATP bus center project