In the Les Halles district, GA Smart Building is carrying out a full energy and interior renovation of the CNES headquarters, a building constructed between the 1970s and 1980s.
The 9,200 m² renovation of the CNES (French National Centre for Space Studies) headquarters was awarded through a public tender. After signing a lease of over 20 years with GENICA, the building’s owner, CNES aimed to modernize the premises by redesigning the entrance hall and office spaces and creating a rooftop. The project was entrusted to a consortium composed of GA Smart Building, architectural firm SK Associés Architectes, engineering consultancy ARTELIA, and acoustic expert GAMBA.
Ideally located near the Forum des Halles and Saint-Eustache Church, in Paris’s historic center, the building enjoys an exceptional setting, close to the Châtelet–Les Halles station served by RER lines A, B, and D, and metro lines 1, 4, 7, 11, and 14.
This renovation aims to create open, functional, and light-filled spaces while preserving and enhancing the building’s unique identity.
The primary goal is to improve the visibility of the façade. The plaza floor, curtain wall, and entrance doors will be completely redesigned.
The redesigned interior will feature modular spaces, ensuring great flexibility to meet the occupants’ needs. The open-plan structure will include a central patio providing a bright and airy environment.
On the ground floor, the reception area will offer a modern, fluid, and well-lit welcome experience, enhancing the sense of space. The use of illuminated ceiling features and wall finishes will echo CNES’s aerospace identity.
On the first floor, the cafeteria will be refurbished with warm materials to create a spacious and inviting atmosphere. It will be designed as a key gathering space for employees. The patio will be reconfigured to connect with the cafeteria, encouraging social interaction.
On the upper office floors, the design will be contemporary. The installation of glazed movable partitions will bring natural light and transparency to previously enclosed workspaces.
The CNES headquarters renovation will also bring nature into the heart of Les Halles. The rooftop will be transformed into a green terrace, with 175 m² of planters and a wooden deck. This space will support urban biodiversity while providing a welcoming, shared area for employees. It will offer CNES staff an exceptional view of their iconic surroundings.
In addition, rainwater harvesting systems will be integrated to strengthen the project’s sustainability goals and environmental responsibility. As with all its renovation projects, GA Smart Building has reimagined the building to meet current regulatory standards while pursuing high environmental ambitions. The project targets the HQE Bâtiment Rénovation V1 certification, with an “Excellent” level, notably through the use of eco-friendly materials and sustainable design solutions.
Retail spaces located on the ground floor will remain open and operational throughout the works, thanks to a carefully planned phasing strategy that takes construction constraints into account.
The renovation is scheduled to last 20 months, with completion expected in February 2026.
Contact
Gilles De Jouvencel
Managing Director, Renovated Unit
