The design concept proposes lateral extensions to each of the existing wings. This creates a volumetric play in which each of the four volumes faces a different direction. The delicately differentiated volumes are grouped around a central core and introduce a plinth into the new structure. Due to the requested flexibility for future usage, the internal organization allows for classical office layouts and open work landscapes and offers to house one or more tenants.

All interventions are done with great respect for the original qualities of the building - its transparency, design of the façade and the finishing of the interiors – and aim to reuse as much as possible.

The new facades introduces a playful composition with horizontal and vertical orientation, while making this varied mass to appear as one representative volume and identity for the future user. The renovation achieved a BREEAM Excellent rating with the application of sustainable components including the use of water from the Seine for heating and cooling, low energy lights, and a naturally ventilated and sun protected façade.