The Ampère e+ and City Défense buildings form a discreet ensemble within the neighborhood. Separated by a central alleyway, the two buildings differ from each other in shape: one is triangular in plan, while the other is square. Their identical facades meet the requirement for buildings to evolve in shape in order to improve working conditions and reduce energy consumption. The alternating white panels and reflective glass create a two-tone effect that changes depending on the color of the sky.

Sogeprom's ambition in restructuring the building is to put the user back at the heart of the real estate project, in their living or working environment, and sees Ampère e+ as a real laboratory for positive energy. For example, it incorporates new innovative and connected technological tools such as smartphone controls, service management (room and meeting reservations, RIE, etc.) and technical office features (air conditioning, lighting, etc.).

Ampère e+, whose construction began in 2015, was delivered at the end of 2016 and includes:

• 14,200 m² of new-generation office space,
• 200 parking spaces, including 30 for electric vehicles,
• a restaurant and cafeteria opening onto a garden.

Its floors have an average surface area of 1,200 m² over 9 floors and it meets the HQE Excellent, BREEAM Very Good, and BBC Effinergie Rénovation labels.

The Saubot agency was founded in 1964 by Roger Saubot (1931-1999) and François Jullien. The two architects specialized in the construction of high-rise commercial buildings and collaborated with numerous international firms, most of them American. In 1985, they designed the Bouygues Construction headquarters in Guyancourt, in partnership with Kevin Roche and John Dinkeloo.

In association with the renowned Skidmore, Owings and Merrill agency, they participated in the Fiat Tower project in 1964 (renamed the Areva Tower in 1979). They established themselves as the architects of La Défense and worked on 11 projects, ensuring the transition to more energy-efficient and better-lit buildings (Total Coupole, France Télécom, the Veritas offices, etc.).

Roger Saubot and François Jullien then continued their careers working for the Disney Festival at Eurodisney in 1992 and the American Center, now the Cinémathèque Française.