Part of the wave

EL: I think our generation, and the one after us, has found a way to adapt to this new world that’s emerging—how to work in it, how to find projects. Our lesson focuses on resilience and adaptability. We grew up with crises. This is normal for us. So we live with them, we build with them. 

CW: It’s worth noting that we joined Echelle-Un, an incubator for young practices at ENSA Paris-Est. That gave us the chance to observe many of our peers, other architects of our generation, who were starting at the same time—and how everyone was practising. At that time, we launched our podcast series, Making Good Architecture, because we were really curious about how the architects around us were working. And the title itself was about exploring both how architecture is made and what "good" means. Does it refer to social impact? Environmental responsibility? Aesthetic quality? We spoke with architects from our generation to understand why they had chosen to go into practice. What we found was that many were driven by strong environmental values or deep commitments to social responsibility in the way they approach projects— that really resonated with Sierra.  

The former way of practising— the “master” architect dictating everything from the top down—was simply no longer how they worked. They wanted to hear from the engineer, the contractor, the craftsperson. They wanted a kind of architecture that would emerge through collaboration, that would make sense in its context. Everyone wanted to work with the community, with the client, with anyone impacted by the project. To make the project meaningful in its specific context—whatever that may be—by creating a kind of ecosystem of collaboration.

Lessons from across the globe 

CW: I'm originally from Kansas, in the middle of the United States, and Éléonore is from Réunion Island, a small French island near Madagascar. We met after studying architecture, during our urban design program at Belleville in Paris.

I previously worked in New York, and one of the main reasons I returned to France to start Atelier Sierra with Éléonore was this sense of freedom and accessibility. It’s possible to start small here. There are so many firms in France—small ones, two or three people—doing meaningful work, getting access to good projects, and having real impact. But in the U.S.—thanks to the way construction and economics have evolved—you’re facing a much larger machine, a bigger corporate structure. It’s really difficult to graduate with a Master’s in Architecture in the U.S. and start your own firm. But in France, even in school, I saw that it was possible. And I think that’s what makes the scene here so rich and interesting: there’s so much diversity and creativity, because there are so many voices. There’s not just one way to do things.

Éléonore and I started working together during our studies on a project about climate change and sea level rise, back in 2013—trying to transform risk into opportunity for the project. The name Sierra came from looking at a map— we both love cartography. We found the geographic midpoint between Kansas and Réunion Island is near Sierra Leone. Today, I think that name represents our approach: this combination of global perspectives and very different origins. It’s something we try to bring into everything we do. 

EL: When we were at Belleville, we were working on several projects: one about sea level rise and territorial resilience around Paris and the Seine river, called Waterworld. And another one, at the same time, a competition in New York—the Queensway Steps, an AIA Emerging New York Architects Competition. It was around an abandoned railway in Queens, New York. The competition called for ideas to transform it into a park. 

CW: What was really interesting is that, unlike the High Line—which runs through the west side of Manhattan, and some very privileged neighbourhoods today—this railway runs through one of the most culturally diverse areas in New York, maybe even in the whole U.S. It’s an immigrant-heavy neighbourhood, less well-known, and not as well-served. So the design challenge was to make something truly inclusive—something that the community could use and take ownership of. Not just another shiny park or commercial space, but something real. 

EL: It was an ideas competition, and we ended up winning with that proposal in 2014, at the end of our studies. We went to New York to present the project, which was a very exciting moment. I think that’s when we truly realised we wanted to work together and eventually start a firm.

CW: Something interesting to mention is that, since it was an ideas competition, we decided to take the risk and actually bend the rules a little bit. The brief was to design the access points to the new park, but we went beyond that. We walked along the whole line and noticed a lot of abandoned or underused spaces—car parks, old industrial zones, empty buildings. Instead of simply connecting to the park, we proposed transforming those sites into community spaces with programming. So each access point wasn’t just a stair or a ramp—it became an activation node. Like stadium seating facing a baseball field, or a longer ramp to allow food trucks and picnic areas. Very simple public infrastructures, but oriented towards the life that was already there. That project really marked the beginning of Sierra.

Driven by curiosity

CW: After that, we each took time to gain experience in offices. It was really important for both of us to understand how architecture is actually practiced—learning how to handle permits, develop technical drawings, and work on construction sites. We needed that. I worked in Paris for a long time at Arte Charpentier, and then spent three years in New York at AtelierTek, which was very exciting. I was lucky to have fabulous mentors—learning to appreciate the grit of the architecture profession but also to gravitate towards optimists. 

EL: I started in landscape and urban design. Then I went to Abidjan, in Côte d’Ivoire, to work in a large architecture firm called Koffi & Diabaté. It was a very important experience because I had to totally change my context and mindset. I didn’t know anything about Côte d’Ivoire. It’s very different from France or even Réunion. So I had to let go of everything I’d learned in France, be humble, and say, “Okay, I’m here to learn from you.” And the Ivorian architects were so good at what they did—very respectful, very skilled. That experience changed me. After that, I returned to France and worked at Atelier King Kong, where I was involved in large-scale housing projects. 

CW: This idea of forgetting what you know to learn something new is crucial. That’s something we share. We both come from modest, unassuming places—Kansas and Réunion Island aren’t the centres of the world. We’re naturally curious. We want to listen and learn from other people. That’s how we approach our work, and I think it’s something that connects us, despite our very different backgrounds. That curiosity and openness—it always makes me happy to see that in our partnership.

Stories, spaces, cultures

CW: From the very beginning, we established core principles that have always guided our practice. These values form the foundation of our approach, though we believe they should evolve over time. Today, what we’re really focused on—and how we like to describe the way we work—is a local approach with a global perspective. And we feel like that encompasses everything. It’s the overarching idea behind how we approach things. Given our backgrounds that span architecture, landscape, and urban design, we don’t like to limit ourselves to a particular typology. We work between social and bioclimatic architecture and resilient urban design—across all scales, from micro-architecture and ecotourism trails to mediation and transitory urbanism, all the way to regional-scale thinking, like floodwater management. We like to experiment with all scales, but always with the same approach: being hyper-sensitive to context.

EL: We’re also interested in the community and the stories of the people who will live in or use these spaces. As we mentioned with the Queens project, it was crucial for us to understand the people impacted by it—not just to propose a pretty building or park without knowing what the community truly needed.

CW: We believe everybody has a story. Everyone comes from somewhere and has a distinct way of using a building. Across cultures, we’ve observed different ways of sleeping, or using the bathroom—so when designing a space, we must remember that every culture has its own customs and habits. We have to understand that to avoid accidentally forcing people into a different way of living. If we want our projects to have a real impact, we truly have to understand how people will use the building, how they’re going to live in it, and what the life cycle will be. It’s not just about functioning on day one—it’s about what the space will be like in five years, in fifteen years. Because the people in that building are going to live their lives there. 

Between landscape and architecture

CW: On the larger scale, we’ve been really lucky in the last year to partner with other firms and participate in public competitions. We worked with Arte Charpentier on a proposal to renovate an old car factory near Paris into a new park and a small café-community hub building. We collaborated with landscape architects, and we designed the small building in the park. We took a risk proposing to adapt and reuse a large portion of the existing industrial structure, which was destined to be demolished—to use this structure to create pergolas, swing sets, greenhouses, and more. We were looking for a way to authentically transform the site without erasing its history. We didn’t win, but participating in the public competition was exciting, and we feel our proposal really encapsulated our respect for each project's history and context.

EL: Another project we’re working on is in Sainte-Suzanne, on Réunion Island—it’s a competition in collaboration with King Kong Atelier, to renovate an old sugar factory into an art and cultural centre. What’s interesting in this competition is that there’s an additional mission beyond just the architecture: urbanisme transitoire and co-conception of the public spaces. On Réunion Island, we live outdoors, so we need areas where people can stay outside while being protected from the sun and rain. In this cultural centre, there will be many open areas—perhaps just an overhang—connecting to nature or the town. There will be buildings, yes, but also very different kinds of spaces. And we have to co-design these in-between spaces with the local population. 

Another important aspect was the large budget dedicated to designing public furniture employing reused materials. As part of this collaboration, beyond contributing to design and research, we also brought contextual knowledge—about the climate and local way of life.

Totems and territories

EL: A meaningful experience for Sierra was the 12 Totems project. It was a great opportunity because it connected a broad territorial perspective with the intimate context of small towns in the Val de Saintonge region north of Bordeaux. One of these towns, Centre-Bourg, needs economic revitalisation, as many young people leave for larger cities in search of work. In this region, there’s a lot of Roman architecture and a strong architectural heritage. There are rivers, forests, and stone that can be used for building. There are resources to highlight.

We had to design and build 12 totems using only two materials. We chose wood—specifically chestnut, which is naturally protected against fire, insects, and so on—and local stone, la pierre de pays. We created micro-architecture with these two materials and proposed a series of variations. It’s the same base structure for all 12 totems, but we adapted each one to its specific site. Each site is about 30 minutes apart by bike, forming a cycling route that links them together. That connection was likely a key reason our proposal was selected—we designed a cohesive network to strengthen the region’s identity and boost its appeal to visitors. Each totem, located in a different town, has a playful or interactive aspect: you have to listen, or pull, or push, or climb.

CW: Since we met, Éléonore and I connected over a shared sensitivity to the environment—we both have a deep love for nature. Even early on, my interest in urban design stemmed from that respect: I saw it as a way to counter suburban sprawl and preserve natural landscapes. This project reflects those shared values and our multiscalar thinking.

Climate and craft

CW: There are a couple of projects that reflect our values and are worth mentioning. One is a restaurant in Réunion Island, which is particularly exciting—it’s for a chef who trained in top international kitchens in Paris and New York and has returned home to open his own place, focusing on local ingredients and a deeply rooted approach. What’s so interesting about this project is that there are so many parallels between cuisine and architecture. The client is sensitive to the question of where materials come from and what it means to place them in a space. It’s exciting to collaborate with someone who has that kind of sensibility. The way he approaches food is similar to how we work with materials in architecture. 

The other project is a brewery for craft brewers near Tours, France. Like the chef, these brewers have a deep sensitivity to the process of making. So, a lot of the language we use in architecture, they understood instinctively—like the importance of ingredients, the process, the time things take. There was such a natural link between what they do and our approach to architecture. That’s something we want to explore more—working with craftspeople and makers, and seeing how architecture can support their world of fabrication. We don’t want to lose that link between the act of making and the architectural process. 

EL: We are also interested in the rehabilitation of old and historic buildings for living with the climate. We have one project near Bordeaux, a very old stone house, and we’re rethinking its uses. It’s interesting because we’re asking: what new materials can we introduce that still respect the history and the way the building works? Stone walls have specific qualities—they’re naturally cooling, and they need to breathe. So the question of how to intervene is complex but fascinating.

Then, in Réunion Island, we’re working on the transformation of a small concrete house into a tropical villa with indoor and outdoor living spaces. The existing house is very basic, totally unsuited to the local climate, but we decided to keep the existing structure. We can build on top of the base that’s there, and we think it’s useful to keep as much material as possible. We can rethink natural ventilation and passive solar protection. It’s fascinating to rehabilitate what we might call ordinary patrimoine. It’s not an official heritage site, but it tells the story of a certain time in Réunion, when this type of house was built everywhere. It feels meaningful to transform it.