Learning to build

CDG: We believe France is an exciting place for a new generation of architects for several reasons. One key factor is public policy aimed at helping young architects secure projects. Landing that first project and establishing a practice has always been difficult, but it seems the government is now recognising this challenge and providing support, creating opportunities for young firms to experiment and explore new ideas. Another notable aspect in Paris is the encouragement of collaborations between established and emerging firms. It’s becoming more common for multiple offices to work on a single project. As for our practice, it was a gradual process. The three of us had worked in different firms for five to ten years before starting our own. We met when the three of us were working at the same agency. We realised we shared common views on architecture and its broader purpose and decided to give it a try. We started with small projects, gradually building our practice by doing the work rather than beginning with a fully formed philosophy. 

Beyond architecture, we are also an engineering firm, handling structural calculations for buildings. Our engineering work isn’t about creating a distinct aesthetic—it’s simply part of how we operate. It allows us to work on our own projects, collaborate with other practices. This technical approach is especially valuable for refurbishment projects, where understanding structures and their limitations is crucial. In fact, our first projects were all focused on refurbishment. In France, this is becoming increasingly important because so much has already been built, and the focus is now on transforming existing structures. We enjoy the heritage of existing buildings—their volumes, their emotions. It became the main focus of our practice. 

Making the right decisions in transformation

CDG: With refurbishments, the process always starts with studying the building’s history and doing a thorough diagnosis. We assess the building’s condition, then decide how to approach the transformation. We begin with a vision, but the diagnostic phase continues throughout the entire project, even during construction. We constantly discover new things: we know our intentions, but the final result takes shape along the way. It’s an evolving process, where we focus on what’s important in the building—what’s relevant for the future and for the new uses it will have. Every project is different. Working on a Renzo Piano building is different from working on a modernist structure or an industrial ruin. But the goal is always the same: to reveal the quality of the existing construction rather than making it look brand new. We always try to preserve as much as possible, but without being dogmatic. Sometimes demolition is necessary, and that’s okay. The key is to be smart about it—analysing the building carefully and deciding which parts to keep and which can be removed to create something new. It’s about making the right decisions. And for us, that gives meaning to our work.

An interesting aspect of working with existing structures is that, in some ways, they offer more flexibility with regulations. New buildings must adhere to strict rules, leaving little room for negotiation. While certain aspects, like fire safety, must be followed precisely, there’s more space for discussion when it comes to structural changes, and other elements. The same applies to heritage regulations, where political views vary—some aim to preserve history unchanged, while others push for radical transformation. The challenge lies in navigating between these extremes to create a meaningful project. In France, there’s the Architecte des Bâtiments de France, who oversees heritage regulations. In Paris, they review projects and decide whether they align with heritage guidelines. But we don’t see them as adversaries—it’s a dialogue. Sometimes they have one vision, we have another, and we negotiate. If you approach it as a conversation, you always find a way.

A dialogue with recent history

CDG: We work with buildings that are part of the 20th-century heritage. It’s interesting because, as architects, we shape the narrative. We define what is valuable in a building, and once that vision is agreed upon, it becomes the project’s foundation. In this process, we decide what elements to highlight. If the client and team agree, we move forward, and in a way, we’re defining its legacy. It’s a fascinating dynamic because every project becomes a discussion about what’s worth preserving.

For the La Halle de Rouvray project, located in the renowned Parc de la Villette, the building was a former factory, practically in ruins. Funding was secured to reconnect it to the Parc, which was a great idea. Our role was clear: first, reestablish that connection with the park, and second, preserve the materiality we found compelling. Fortunately, since the building wasn’t subject to strict thermal regulations—it’s an open volume without heating or insulation requirements—this made it easier. We had to reconstruct the framework, repaint, and replace certain elements to stabilise it. The roof had to be entirely redone because it was collapsing. Our goal was to retain the essence of the place, and we realised the walls were key. They were deteriorating, with exposed bricks and layers of graffiti, so instead of covering everything up, we simply had the workers clean and stabilise them. 

With refurbishment, the process itself often tells the story. In La Villette, we had to replace parts of the structure while keeping others, so it became a meticulous task of mapping each element. At one point, we considered marking the new structural pieces with a different colour from the original ones to showcase the process. But in the end, we felt it would be too demonstrative and disrupt the overall aesthetic. While we value transparency in showing how a building evolves, the final experience for those using the space matters just as much.

We had a similar debate with another project, La bourse d'affrètement de Conflans-Sainte-Honorine, a modernist concrete building by the Arsène-Henry brothers. It’s a beautiful structure, reminiscent of Le Corbusier, with perfectly composed volumes. The concrete was deteriorating, cracking, and falling apart, so we had to restore it for longevity. We faced a choice: match the original pigment exactly to make it look brand new, or embrace the restoration process. We decided to let the repairs remain visible—so now, the original concrete has a warm yellowish tone, while the new patches are slightly gray. It might look unusual, but we like that it shows the history of the building’s transformation.

Honouring the past, designing for tomorrow

CDG: Every project starts with research. In some cases, like Rouvray, the industrial buildings have no known architect, whereas in Conflans-Sainte-Honorine, we worked with a structure by Arsène-Henry, well-known in France. For another project, we studied an early work by Renzo Piano, built in 1991, and carried out its rehabilitation: Thalès Factory (formerly Thompson). This was a particularly complex competition because there was no set program. We had to propose a new use for the building while keeping it adaptable for future needs. Our idea was to phase the refurbishment over time—starting with certain interventions, then adding more in two, five, and ten years. It was a long-term strategy that considered both function and financial feasibility. At the same time, we wanted to restore some of the original design intentions. The building had changed over the years, and one of Piano’s key concepts—a central street—had been disrupted. We proposed realigning it and redesigning the façade in a way that respected the original structural grid but incorporated new materials. 

Last year, we also worked on two exciting projects. One was the refurbishment of the Simone Signoret Theatre in Conflans-Sainte-Honorine. It’s a completely different type of heritage—a 1980s building that, at first glance, isn’t particularly appealing. When we were assigned the project, our first reaction was, "What is this strange building?" But it turned out to be a fascinating challenge. As a cultural venue, it’s all about how the public and artists interact with the space. Our intervention focused on exposing the existing structure while making a more radical transformation to the façade. The goal was to create a new visual identity while still highlighting the building’s unusual shape. 

Another big opportunity last year was our participation in the competition for the refurbishment of the Centre Pompidou—Beaubourg. It was a major project, another Renzo Piano building. We teamed up with Kuehn Malvezzi and CALQ, which was a fantastic experience. Like always, we started by thoroughly analysing the building, trying to understand its fundamental principles and how best to intervene. Our proposal was well-received and selected for the final round. Even though we didn’t get the project, we were proud of our approach.

Drawing the transformation

CDG: In all our refurbishment projects, we enjoy the process of discovering a building, transforming it, and giving it new life. To achieve this, we use a wide range of tools. We carefully document each phase—the initial state, the construction process, and the final outcome. We’re not sure yet what we’ll do with all this material, but we use two main media for documentation. One is photography, a more conventional approach that captures the transformation of cities over time. The other is large-scale drawings, which we work on with Cynthia Walsh, a friend of ours who is both an architect and a draughtswoman. She focuses entirely on drawing and teaches it in architecture school.

We started with the idea of drawing the building at different stages—when we first discover it, during construction, and then after completion. These drawings capture the spirit of the place, its materiality, and spatial qualities in a way that photographs cannot. They allow us to highlight different aspects of the process.