Agrarian traditions run deep in the Lesponne river valley of southern France, so it comes as no surprise that Puig Pujol & Associés Architectures sought to respect the environment when designing a 540-square-foot home addition. A retired couple commissioned PPA to add a guest room, garage, and extra living space to their country getaway—a barn that’s over 100 years old.

In deference to the rural surrounds, the Toulouse, France–based firm extracted a portion of the hillside adjoining the original house and slipped in a glass, steel, and concrete structure underneath. “A topographic feature of the utmost discretion,” says firm principal Jean-Manuel Puig of the stealthy design that barely peeks from under a blanket of grass.

PPA had to court the French government in order to secure authorization to build. Luckily, the caliber of the project and its sensitivity to its setting “seduced” France’s national architect, who placed his seal of approval on the project—a highly successful marriage of a contemporary architectural vocabulary and vernacular influence.