“It’s not such a big deal to convert dwellings into dwellings,” jokes Xavier Brunnquell, founding partner, alongside Axel André, of Paris-based architecture office Brunnquell André. He’s referring to the transformation, led by his firm, of the Caserne Exelmans—a barracks for the Gendarmerie, France’s military police force, located in Paris’s 16th arrondissement—into a mixed-use complex containing a homeless shelter and affordable rental apartments. While it’s true that the ensemble’s dimensions and ceiling heights lent themselves to its new role, the required upgrading and reconfiguration were nowhere near so simple as his quip suggests. Indeed, the operation’s successful conclusion was in large part due to its long time frame, which stretched over a 10-year period from 2016 to today.

The story’s origins arguably go back even further, to the early years of the millennium, when the French government enacted legislation obliging every agglomeration of over 50,000 inhabitants to increase its public-housing provision to at least 25 percent of the total available stock. Besides aiming to ensure sufficient accommodation for lower-paid key workers, the law sought to promote better social cohesion by avoiding ghettos of rich and poor. Notoriously, some of the wealthier municipalities—most famously Neuilly, on the edge of Paris, France’s highest-earning commune whose longtime mayor was Nicolas Sarkozy—resisted, opting to pay fines rather than comply. And even within a city like Paris—which, governed by the Socialist Party since 2001, has now reached the goal—there were pockets of defiance, such as the famously bourgeois 16th arrondissement, which borders Neuilly. Therefore, when the gendarmes announced their intention to leave the Caserne Exelmans for new barracks in the suburbs, city hall seized the opportunity to redress the balance.

Brunnquell André’s involvement with the site dates back to 2016, when Paris Habitat, a municipally-owned public-housing provider, commissioned the studio to undertake a feasibility report to help it in negotiations with the Ministry of Defense. Constructed by architect Julien-Michel Morize in 1907–09, the barracks took the form of an ensemble of six freestanding buildings in brick, ashlar, and rubblestone, with a main entrance block of seven stories (including attics) on the boulevard to the northeast; two five-story lateral wings behind forming a courtyard; and a two-floor stable block with a clocktower closing the rear of the court to the southeast. In the corner between the stable block and the northwest lateral wing was the single-story bathhouse, while the captain’s residence stood on the boulevard to the northwest of the entrance building. Demolished during a 1980s modernization program, the captain’s house was replaced by a six-story stone-faced accommodation block in concrete, while the remainder of the ensemble was upgraded with PVC window units and mechanical ventilation.

As Brunnquell recalls, after the gendarmes vacated the barracks, in 2018, the city organized a “competitive dialogue” that sought “a method rather than a design” for the transformation. For this stage of the process, the firm teamed up with Yoshiharu Tsukamoto of Tokyo office Atelier Bow-Wow, whose practice has a long-held interest in repairing and mending. “Yoshi was our anthropologist,” explains Brunnquell. “He helped us understand the relationships between the future occupants in order to build a shared narrative.” The final project also took on board lessons learned from the site’s 2018–23 occupation by Aurore, a charity that runs emergency accommodation for the unhoused.

As completed today, the ensemble comprises four principal programs. While the main entrance block and the northwest lateral wing contain 50 affordable dwellings, the southeast lateral wing is home to a 53-bed shelter for the homeless; the 1980s building contains 26 studio apartments for people in situations of precarity, while the stable block houses a children’s daycare and medical center; as for the bathhouse, it has become a meeting space for local societies and associations.

In its original state, the northwestern wing comprised two halves, each with its own staircase. To convert it into a homeless shelter, Brunquell André united the whole with corridors, installed an elevator, and turned the attic into bedrooms by adding dormer windows. For the daycare center, the firm built a small metal-clad extension to the southeast, which allows for a rooftop play area hidden behind tall fencing. Where the affordable dwellings were concerned, “the apartment typologies were suggested by what was already there,” says Brunnquell. The result is 27 variants ranging from single-person studios to four-bedroom family homes; a little bigger than today’s standards, many of them feature large kitchens that can also serve for dining. At one end of the entrance wing, a lightweight infill extension provides extra bedrooms for the adjoining apartments, while throughout the complex, in line with Paris Habitat’s energy-consumption objectives, perimeter walls are clad internally with a 6-inch-thick layer of insulation.

What makes the project especially rich is the way it respects the spirit of the 1909 building, with fixtures and fittings recuperated on site or brought in from other properties of the same era. Before work began, Brunnquell André made a thorough inventory of everything that might be reused or recycled, from floor coverings and doors to radiators and sanitary equipment. In the completed project, reconditioned parquet floors preserve traces of former occupation; tomettes—hexagonal terra-cotta floor tiles, traditional in France since the 18th century—have descended from the attics to the apartment kitchens; restored iron stair balustrades feature carefully detailed inserts to meet today’s code; while 300 paneled wooden doors, ripped out of another Paris Habitat property because they were no longer compliant with fire regulations, have transformed into wardrobes, cupboards, room dividers, wainscoting, and even plant containers. Outside, the architects repaired the roofs, replaced all the windows with new timber units, reinstalled long-lost wooden shutters, and gently cleaned the masonry to preserve a little of its patina. All of this care and effort, they say, was brought in for a slightly under-average cost thanks to the diligence of the main contractor.

Brunnquell’s one regret, in an otherwise exemplary operation, is the courtyard, which he imagined far greener and tree-filled. But, because of the two staircases in the homeless shelter, the fire services refused, insisting their trucks come right in and park on a hard, stable surface. In light of France’s record-breaking heatwaves, the architects hope to renegotiate this stipulation.