A journey of tenacity

LR: Paris has always been a hub of creativity and innovation, but there’s a sense that something unique is happening nowadays in the architecture scene. Paris feels like an endless city, offering space for countless voices and expressions in architecture, society, and beyond. Perhaps the increasing number of emerging practices is linked to this moment in time, where people are seeking new ways to express themselves—both as a response to the current era of uncertainty and as a reflection of life in a metropolis like Paris. There is a major change regarding the architectural attitude: closer to materials, resources, and the constructive process. New generations are “learning as they go” to think about architecture in a new way, adapting to new constraints, such as carbon footprints, thermal comfort, energetic performance, and natural materials. It is an exciting moment for architects, as we have the great opportunity to build in a more responsible and lasting way.  

As for my personal trajectory, I studied at ETSAM in Madrid and completed my degree in 2011, just after the 2008 financial crisis. There wasn’t much work for architects in Spain, so my generation went abroad—my friends scattered across different countries. I had already lived in Vienna and considered staying in the German-speaking world, but I sent portfolios everywhere searching for new opportunities. I don’t know if it was destiny or just chance, but I ended up in Paris. I started with a small internship, but it was tough—I didn’t speak French. Arriving in a new city, not knowing the language, knowing no one, and trying to start my career as an architect—it wasn’t easy. That first experience wasn’t quite the right fit for me. Then, I started working at Jacques Moussafir’s office, where I met Jérôme (Hervé), my partner both in the practice and in life. 

It was during this time that Jérôme and I decided to start our own practice. Jérôme launched Heros in 2016, but as we were also a couple, we wanted to minimise the financial risks of starting an emerging office. So, it felt natural for me to join him two years later, in 2018. At first, we focused on private clients—small refurbishments and extensions. But when I joined, we reconnected with some of my former offices. That marked a turning point, allowing us to step into larger-scale architectural projects in parallel with the smaller and more domestic ones. We try to remain polyvalent and open-minded.

Designing through dialogue

LR: Right now, we’re working on everything from a 35-square-meter renovation to a new house, to a 120-unit collective housing project on the outskirts of Paris. That kind of range is essential to us—it keeps things dynamic. We give the same level of attention, passion and creativity to a small project as we do to a large one. At first, we were mainly working on private flats. But then, we were invited to participate in a selection process for a project in Villeurbanne, near Lyon. 

Villeurbanne’s historic centre was built as social housing in the early 20th century and features France’s first steel-structured skyscrapers. The public developer and urbanist were selecting three teams of three architects each to co-design the expansion of the historical axis. Our team included Hardel Le Bihan (architecte mandataire), Plages Arrière (a local architect), and Heros (the young office). We advanced to the final round, which involved an oral presentation. Unlike other teams that focused solely on architectural concepts, we approached it from a more personal, human perspective. During the presentation, we described our experience of walking through the neighbourhood, climbing the stairs of the towers, and listening to the people who had lived there for generations. There was also a personal connection—one of the architects from the local team had a great-aunt who had lived in one of the towers since its construction. Maybe that human connection made a difference, and in the end, we were selected.

It was an unusual process—there was no predefined architectural project. Instead, the public developer organised a series of workshops, where each team developed their project in dialogue with the others. The idea was to create a neighbourhood collectively, designing in parallel rather than in isolation. That experience reinforced something we believe in deeply—that architecture isn’t just about form or aesthetics. It’s about dialogue, people, places, and the way stories shape cities.

Navigating political complexities

LR: The experience with the project in Villeurbanne has been both rewarding, as we were selected, and extremely challenging, as the project has yet to begin. Every design decision and architectural choice required approval not only from our client but also from the urbanist, the public developer, the mayor and ABF (Architecte des Bâtiments de France). It’s a reminder of the other side of this profession that we need to learn to work with.

It felt like being part of a huge machine, where even the smallest details—like the colour of a wall or the design of a metal element on the facade—required approval. As we progressed with the design, we worked alongside the other architects, and the validation process became a slow, step-by-step journey. Then, political changes took place—the city of Lyon shifted to the Green Party, and they required more sustainable designs. This led to a six-month pause while the urban project was revised. As a young office, it was challenging. Even today, we focus on balancing smaller projects alongside larger ones, which has become a good strategy to stay active.

What was particularly difficult about this project, which was highly political, was the feeling of not being in full control of the design. You realise that decisions are not entirely yours—urbanists dictate the city’s shape, and the ABF has a say in many design elements. The process was long, and after several years, the project’s financial and economic aspects became more complex due to the uncertain geopolitical situation in recent years, which led to rising prices. Ultimately, you feel somewhat stuck, caught in a political context, with the building site yet to get started. Eventually, this long process forced us to develop a pragmatic approach with an essentialist design strategy. 

This kind of political complexity is nowadays very usual in Paris, even in small-scale projects such as our office project Aicard, situated in the 11th arrondissement. In this case, the project consists of a restructuring and elevation of an existing building from the beginning of 20th century. As an act of reparation and resilience, the difficulty resides in responding to a client’s demand as well as the ones coming from the mayor of the arrondissement, the city of Paris and the ABF. Dialogue, consistency and architectural principles, together with tenancy, become really important aspects of the project. It can take years to obtain the building permit, but this kind of project is definitely emblematic of our time as it allows to rebuild the city on itself. 

Single units become collective housing

LR: In our work with social housing, we pay close attention to the housing plan itself. This is one of the key aspects of our practice: we believe that a family living in a stand-alone flat should have the same quality of life as one living in collective housing. Our work on smaller-scale projects constantly informed our involvement in larger-scale interventions. For us, both private and collective housing should offer the same qualities, and that’s what we strive to develop in our office.

In this sense, we understand collective housing as a collection of family units, including new constraints such as vertical superposition, urban context interactions, technical and structural inputs and regulation complexity. Both scales of the project deal with the everyday lives of future inhabitants, and they should require as much work and effort from the architecture practice as possible. 

Pushing the boundaries of materials and efficiency

LR: We are currently developing an ambitious project in collaboration with Atelier Villermard Associés in the Chapelle-Charbon new development zone (ZAC), located in the 18th arrondissement of Paris. This large site once belonged to SNCF, the French national railway company, and was transformed into a park in 2020. The site had been part of a large social housing operation in the 1990s, but today, it faces a challenge: the existing buildings have blind facades facing this new park. In Paris, living in front of a park is extraordinary and extremely rare, so the city and public developer aimed to create a new set of housing buildings to face the park and integrate green corridors, aligning with the existing social housing. Our project will feature 78 social housing units, shared spaces, and commercial areas.

The public developer, Paris & Metropole Aménagement, launched a competition for several new buildings, including three main buildings facing the park and two larger buildings with nine or ten stories. Each site is developed by an architecture office, some of them already well-known as Bruther, Rafael Gabrion and Clément Vergely; others are emerging practices, like Hub + Nicolas Lombardi, Palast, and Heros. What was exciting about this opportunity was the public developer's emphasis on high environmental and technical performance expected for the projects. They worked with some of the best experts in the field, including, a renowned urban planner and architect (h2o) and landscape architect (Base), and top engineers specialising in bio-sourced materials and new construction techniques (Laurent Mouly) as well as environmental aspects (Franck Boutté). The programme set the environmental expectations incredibly high, and when we received it, we were both impressed and overwhelmed. But it also pushed us to think about how we could meet these standards. We decided to use stone, a material we hadn’t worked with before. It appeared to us to be the better choice to reduce the carbon footprint and take advantage of its thermal inertia. Stone, especially limestone, is a key feature of Paris architecture, and we thought it would help bridge the architectural language of the new buildings with the city’s traditional character. 

This project began with little knowledge of stone, and the learning process was intense but rewarding. We ultimately won the competition by using this material not only for the facades but also inside the building, in walls separating the flats, allowing people to live in direct contact with it. The use of limestone inside the flats connects the public and private spaces uniquely, and it also contributes to the building’s thermal inertia. 

A good project comes from a good client; in our case, it also comes from a good urban and developing programme. These ambitious environmental requirements made it “easier” for us as architects because we didn’t have to convince the client of the importance of sustainability or performance. These aspects were already rooted in the initial programme. Throughout the design process, we had to be constantly aware of the carbon impact, energy consumption, and the building's overall performance. As architects, we couldn’t simply make decisions without considering how they would affect the project as a whole. Everything is interconnected, and each adjustment affects the final outcome, so we worked closely with the engineering team to ensure the best possible results. Today, it's no longer about what the architect simply wants; it's about making sure that the solutions we propose actually work in real life.

Low carbon, high stakes

LR: You try to avoid using too much steel and concrete, as was done in the past, but when it becomes too expensive for a project that's already at a good level, you have to add other materials to balance the costs. The issue is that as soon as you introduce materials like steel and concrete, the carbon impact increases. Finding the right balance between carbon and costs is the key to achieving a project.  

For instance, in the Chappelle-Charbon project, although we worked with limestone—which is excellent in terms of carbon impact, as it can be used with minimal transformation straight from the quarry—we still didn’t meet our carbon goals. To improve on this, we incorporated reused steel elements for the balconies in the inner courtyard. This counts as zero carbon, which is a clever way to balance out the environmental impact. But technically, it’s complicated. How do you prove that the reused steel works well in terms of structural calculation or fire safety? 

Therefore, all these aspects together make projects much more technically demanding from the start. For a young practice like ours, it can be as overwhelming as intellectually exciting and challenging. The best way to approach it is to learn—stay close to the materials, attend lectures and trainings, meet people in the industry, and work closely with your engineering team. If you don’t push beyond the basic architectural solution, you can't really work with these constraints in a meaningful way. Without this understanding, your project can end up just being a response to these technical constraints, rather than a true architectural position.

In Paris, experimenting with materials is increasingly becoming a political act. The challenge lies in striking the right balance.