Revive the Modernity : The Refurbishment of the 3M Tower in Cergy-Pontoise

École nationale supérieure d'architecture de Paris-Val de Seine, Paris

Project idea

The New Town of Cergy-Pontoise sprang up in the late 1960’s in France. This is at the beginning of this new urban experiment, based on green spaces, separation of circulations (pedestrian footbridge, concrete slab urbanism, etc..), that Paul Depondt, an ancien student of Mies van der Rohe, built the 3M Tower. This one had a significant role in the urban and architectural development of city. Unfortunately, fifty years later, this office Tower with its special plastic structure is now disrupted by a project led by Nexity. This building which participates in the skyline of the city, is being demolished to create a new neighborhood with 1370 dwellings. Faced with this analysis, we decided to propose a counterproposal, in order to see how this corten steel tower could have been preserved and become an advantage for the evolution of Cergy-Pontoise.
Perpetuating the memory of a building which is destined to disappear, this project is also a manifesto of an architecture considered as a resource in materials and symbols that should be reinvested and preserved as a trace of our modern history.

Project description

In order to reaffirm the link between the building and the city of Cergy, the project proposed a “return to the ground” of the site by decaying the former basement of the Tower. The creation of a forecourt, a new centrality, organizes the new district. It aims to strengthen the university aspect of the city, overcome the growing demand for housing and preserve the existing park around the Tower.
Within the Tower, the base is re-invested by a multifunctional equipment (library, university archives, cafeteria, conference hall, sports hall and exhibition hall), while the commons floors are renovated into duplex dwellings (110 dwellings at the maximum). The complexity of this project comes from the renovation of this tower which combines these two programs, both public and private, open and intimate, in order to demonstrate the impressive adaptability of this building.

Technical information

Attentive to the economy of construction, we simply chose to do several subtractions to the building to refurbish the building.
In order to add new circulations to the huge vertical circulation core (18m x 21m), we removed several elevators and punctually knocked down its walls. So we were able to reorient vertical circulation core. The longitudinal circulation is now combined with transversal entrances. These new openings bring a new interpretation of the Tower and the vertical circulation core tends to become the real point of articulation of the project.
The substitution of the former concrete beams of the ground floor into castellated beams and the developement of winter gardens assure a visual and functional importance to the basement.
In the upper parts, the creation of some patios and loggias bring more light into the building. And finally, concerning the common floors, rather than focus on defining floor surfaces, we decided to propose duplex which remind the use of multi-storey frames of the existing structure by the subtitution of some concrete floors into a lightweight steel structures.