The first challenge was to take the sheer scale of the undertaking and make it understandable at a human level. For the Duo Towers, everything is outsized: the surface areas, volumes, structural stability, the shell of the building, and its facades… but also the number of people involved, with more than 200 engineers and 1,000 highly qualified workers present on the site during peak periods. Above all, it was a project that no one person could claim to grasp in its entirety and that only teamwork could bring to a satisfactory conclusion.

VINCI Construction brought to the Duo Towers its know-how in the upstream processes, its skills in methodological and structural studies, its creativity, and its capacity to mobilize people around a project. It was an exceptional operation that pushed everyone involved to their utter limits. I’d like to emphasize, in particular, the painstaking work carried out on the towers’ complex structure – built, first of all, out of concrete, then of a mixture of concrete and steel and, finally, of steel – set at an incline with a cantilevered fan-like structure. All of this required a very precise understanding of changes in load displacements from the provisional to nominal phases. What is more, the closure of the volumes as the structural work progressed required conceptual fine-tuning and a sophisticated process for installing the facades along with the use of highly advanced logistics. Only the tip of the organizational iceberg was visible on the construction site with the production and supplies tracking system.

The great success of this building also derives from the quality of its design and the ability to imagine the needs of future users very early on. The best example of this is the objective of obtaining an extremely high level of certifications. The Duo Towers are certified compliant with Leed Platinum, HQE Exceptional, Well Platinum, and have also been awarded the Effinergie+ and Wiredscore Platinum labels. They are also among the very first buildings to seek the WELL and Wiredscore certifications, which more specifically address the well-being of occupants and the provision of digital infrastructure to meet constantly changing connectivity needs.

We tell ourselves that what, for a time, used to be our construction site will always remain the building we built!