From Heritage to Regeneration: Kardham transforms Groupama’s historic Astorg headquarters into a low-carbon urban landmark

Astorg, a reinvented heritage asset in the heart of Paris

Ideally located close to Boulevard Haussmann, the Palais de l’Élysée and numerous CAC 40 headquarters, Astorg benefits from a strategic, high-value location at the heart of Paris’s economic power center. Designed in the late 1950s by architect Ernest Couture, the building has served as Groupama’s historic headquarters since its inception.

For the Group, the challenge was to renovate without altering its identity: to modernize a landmark building while reaffirming its attachment to a historic address and projecting it into the future.

Unlocking the potential of the existing structure

The operation carried out by Kardham and its partners involved the large-scale rehabilitation of 17,050 sqm, including a 1,100 sqm courtyard extension. The project aimed to extend the building’s lifespan and adapt it to new uses while leveraging its original spatial and construction qualities.

To achieve this, the teams prioritized frugality and reuse: a significant proportion of materials were reused — raised floors, carpets, sanitary fittings, stone, furniture — along with the 400 auditorium seats, carefully dismantled, stored and reinstalled.

The headquarters now offers flexible and modular workspaces, a 400-seat ERP-classified auditorium, a conference center, collaborative spaces, a staff restaurant, archives and support facilities, landscaped outdoor areas — including a rooftop garden also classified as ERP — as well as a 180-space underground parking facility, a rare asset in this central district.

Opening up to the outdoors, with nature at the heart of the project

The garden-side extension provides an additional 1,000 sqm across several levels, seamlessly integrated with the main volume. Designed to expand without weighing down the structure, it relies on a timber structure with cross-laminated timber (CLT) floors combined with a metal exoskeleton. This construction choice embodies a lightweight, reversible, low-carbon architecture that opens up new usage perspectives and strengthens the connection to the outdoors.

Nature plays a central role in the project. The landscaped north and south gardens, vegetated continuous balconies and rooftop terrace together represent 2,000 sqm of green space, creating a breathing and convivial space within the dense urban fabric of the 8th arrondissement. These outdoor areas encourage interaction, relaxation and improved quality of life.

An experimental urban greenhouse has also been installed on the roof. Developed in partnership with the AgroParisTech Chair of Urban Agriculture, it transforms rooftops into living spaces and extends the renaturation and greening process within the Paris region.

A demanding environmental approach

Astorg is part of a comprehensive climate action strategy structured around three pillars: energy, materials and carbon frugality.

Energy performance is enhanced through bioclimatic design, high-performance technical systems and renewable energy production, ensuring effective decarbonization and improved climate resilience. Materials are addressed through sobriety and reuse, combined with low-carbon and bio-based materials, while the reversible timber-and-metal extension reflects the ambition to integrate innovative and sustainable construction solutions. Carbon frugality serves as the guiding principle, aligning the project with an ambitious low-carbon trajectory, anticipating France’s Tertiary Decree objectives and incorporating life-cycle analysis from the design stage.

These choices have enabled Astorg to achieve an exceptional multi-certification trajectory: HQE BD 2016 (V3) Exceptional (10*), BREEAM RFO 2016 Outstanding (first renovation project in France at this level), LEED v4.1 Gold, WELL v2 E+C- Gold, BiodiverCity Performant and Effinergie Rénovation E3C2.

They also demonstrate Groupama’s environmental and societal commitment in making Astorg an inspiring and responsible workplace, built on resilient, sustainable and regenerative design principles.

« Astorg is more than a building — it is our home and our historic headquarters. By choosing to rehabilitate it, we sought to combine heritage and future, creating lasting and desirable value. Above all, we aimed to translate our daily commitments to social and environmental responsibility into this project. Astorg embodies our convictions in anticipation, mitigation and adaptation. We are convinced that it is urgent to anticipate climate and societal changes, mitigate our carbon footprint and adapt our buildings to tomorrow’s uses and conditions. With Astorg, we demonstrate that it is possible to meet the highest environmental standards while creating value for both employees and the city,”
Roland Cubin, Deputy CEO, Groupama Immobilier

« By renovating Astorg, we wanted to demonstrate that the existing can become a resource for building a sustainable future. We sought to reveal the building’s potential while respecting its history, profoundly transforming it to meet contemporary expectations. The timber extension, vegetated balconies, rooftop greenhouse and reuse of the auditorium seats all create a dialogue between heritage and innovation. We believe that the architect’s role is no longer to create a statement, but to create connections. Building today means doing less, doing better, and above all building with — for a livable future. Working with the existing enhances beauty and sensitivity, embracing what is already there as a framework for the future. Astorg is a wonderful example of this,”

Chantal Aïra-Crouan, Partner Architect and Director Paris Île-de-France, Kardham Architecture