This project consists in turning an existing office building from the 80s, into a mixed building hosting laboratories and student housing. The initial concrete structure is preserved, and the two programs superimposed on top of each other. The base is enlarged in order to host the laboratories. The superimposition allows to create a sunken garden and to avoid a strict alignment along the street. The deepening of the existing building with a light metal structure provides the project with the identity of an urban scaffolding integrating new outdoor spaces.