The First Tower is one of the most spectacular renovation projects in La Défense. The First Tower replaces the former Axa Tower and increases its height, creating a slender, helical structure against the Paris skyline. The 50-meter elevation of the existing tower is just one aspect of the technical challenge of this project, which also involved widening the existing floors and demolishing and rebuilding the central core.

Particular attention was paid in its design to the well-being of its future users. The First Tower thus favors unobstructed spaces to facilitate interaction and places the restaurant areas on the top floors, with prime exposure. In addition, the choice of ventilated double-skin technology maximizes the proportion of glazing on the façade, in addition to improving thermal performance.

With its entrance hall, maximum natural light, and openness to the city, the First Tower breaks with its predecessor. The tapered design of its top reinforces its image as a flagship.

Founded in 1976 by William Pedersen (1938), Eugene Kohn (1930), and Sheldon Fox (1930), Kohn Pedersen Fox Associates follows in the footsteps of its predecessor, Skidmore, Owings and Merrill. Specializing in office towers, it operates worldwide. Since the 1990s, it has designed numerous “iconic” buildings such as the Adia Tower in Abu Dhabi and the Shanghai World Financial Center. In 2012, the firm completed the Pinnacle Tower in the heart of the City of London. In La Défense, it is involved in three projects: CBX, Logica, and First.

SRA Architectes was founded in 1996 by Jean Rouit, Hervé Metge, and Clémence Fiant-Saubot, daughter of Roger Saubot, Rouit's former employer. The firm quickly specialized in large-scale projects in collaboration with leading names in the architectural world.

In La Défense, the firm partnered with its American counterpart, Kohn Pedersen Fox, for the renovation of the Logica (formerly EDF-GDF) and First (formerly UAP) towers, as well as for the construction of the Dexia tower (now CBX) in 2005. SRA Architectes also participated in projects for the Défense Plaza building, the Carpe Diem tower, and the Phare tower (a project abandoned in 2015).