The scheme was determined from the outset by a double requirement: to maintain an existing building and to increase its area to adapt to the teaching and research needs of the university’s Cellular Biology and Genetics departments. Built at the beginning of the 20th century for military use, the building was still outdated even though it had undergone several refurbishments. The need to maintain the facades and structure and at the same time to double its surface urged, on the one hand, to add one floor on top of the two existing ones and, on the other, to raise a new volume on the west side of the plot. The teaching and research laboratories go up along the eastern front; the communal services, stairs and accesses to the north and south of the existing volumes; and the main corridor to the west of the laboratories. The new volume accommodates offices, lecture halls and meeting rooms.

The concrete structure is reinforced with a metallic structure, leaving the necessary separation above the beam reinforcement to let the services through. The third floor, extended over the original construction, consists of a metallic structure of beams, pillars and composite slabs. The systems, all exposed, are organized from large openings parallel to the main corridor, connected to the installations on the roof.

The west facade – the only one that has been transformed – is made of polycarbonate, a material which ensures even lighting in the building corridors. The remaining facades of the extended third floor are enclosed in a black deployé rendering, with no windows and just roof skylights. The north, south and east facades stay the same except for the openings. The windows that are no longer necessary are closed with large galvanized sheets. Those of the south and east facades are designed with deep embrasures, also of 8 mm-galvanized sheet, which bring light into the laboratorires, restrooms and dressing rooms.

The building looks out to a large landscaped area of the west side. The glass facades and a continuous concrete pavement stretch the interior spaces out towards the garden. The rooms of the two upper levels look out to the trees, protecting their spaces from sun exposure. The offices have elongated openings at eye level, and the meeting room has a deep brise-soleil, these spaces enjoy homogeneous lighting and become a privileged place from which to observe how the seasons change as well as the reflections of the trees.