The project takes place at the heart of the “Rive Gauche” neighborhood with very high ambition in term of sustainable development. Of simple and compact form, it is through the the thickness of the facades that the materiality is offered to the whole construction. The building is composed of three entities, a base, a body and an attic. Each entity expresses a relation to a specific environment. The base, solid and protective, consists by housing with private exterior extensions. The body seeks to offer specified exterior dilatations through the treatment of the various terraces stretching like shooting lines towards the landscape. Vertically linked by twisted blades, it constitutes an environmental skin combining the thermal qualities with the architectural qualities by a play of vibration of the light and of putting in thickness thanks to the constituted shadows. Finally, the attic sequences the distant landscape by volumes games. The unity is preserved by the establishment of a materiality and declinations of identical colors. The project answers the environmental commitments by rigorous construction, compactness, but above all by the implementation of architectural features offering a quality of life thanks to a quality of space.