Renovation and extension project of an office tower block in Paris HQE certified as Exceptional. The roof is to be redeveloped to make it a planted, accessible space. At 17th storey level, former equipment rooms will be transformed into offices and perimeter walls demolished to create an open façade.

Equipment rooms will be partially moved to the mezzanine and new sealed rooms built into the infrastructure. The stairs/lifts hub will be remodelled to integrate Common Horizontal Circulation (CHC) into the entire building. On the ground and first floors, the creation of a café area and the reduction of the hall involve the demolition of part of the hub and the addition of posts. The extension consists of a 7-floor metal-framed elevation using structural liner trays and the construction of a double-height auditorium in the basement and sub-basement levels. The extension works involve the reinforcement of the existing foundations and the creation of new ones.