Bacalan Block / COSA Colboc Sachet Architectures

Architects: COSA Colboc Sachet architectures
Area: 17700 m²
Year: 2021
Photographs: Ivan Mathie
Manufacturers: KEIM, Kone, LONGISolar, Schüco
Products Used in This Project: Mineral Concrete Stain – Concretal®-Lasur by KEIM
City: Bordeaux
Country: France

Bacalan Block by COSA Colboc Sachet Architectures repurposes an industrial site in Bordeaux, centered around the Maison des Ecluses with its eight 36-meter silos integrated into a vibrant urban landscape. The silos, covered in ivy, anchor the silo garden, featuring ground covers, shrubs, and trees inspired by the Landes forest. Public spaces, including a forecourt, square, and paths, connect the site to the city. A 3-star hotel links the garden to local amenities, while the 4-star hotel leads guests through silos transformed into a lobby and reclaimed spaces. A glass galleria connects the garden to an outdoor café. Rooftop rooms, a restaurant, and a spa offer panoramic terraces overlooking the Garonne River and Bordeaux’s historic center. Concrete facades with lowered window sills frame views, while reflective materials allow the architecture to blend into its natural surroundings.

Bacalan block / cosa colboc sachet architectures

The industrial buildings on this site are remnants of former production processes, now appearing as a collection of objects with varying geometries that no longer convey their original purpose. Within the Bacalan block, the Maison des Ecluses features eight 36-meter-tall silos. These silos, no longer in use, have been overtaken by ivy, which has crept across their surfaces, eroding the concrete and altering its coloration over time.

This setting portrays a still life transitioning into a new landscape. The new constructions are organized around the silo garden, which serves as the project’s centerpiece and backdrop. Layers of ground cover, featuring periwinkles, ferns, heather, leafy shrubs, and flowering plants, gradually transition into umbrella pines, white willows, and geometrically shaped cordylines.

This symbolic forest, inspired by the nearby Landes region, extends into a forecourt, a square, and a landscaped path, all of which have been designated as shared public spaces for the city.

The 3-star hotel links the basins to the garden, which continues through the para-hotel area via a landscaped path that leads to nearby neighborhood amenities located east of the plot, including the tram, parking, and the Vatel Institute.

Guests of the 4-star hotel experience a journey through time as they pass through two silos: the first, hollowed out and seemingly reclaimed by nature, and the second, enclosed by a protective membrane and illuminated by an oculus, which houses the lobby. The silo garden is visible through a glass galleria with sliding windows, enabling the café to extend outdoors beneath white, drop-arm awnings. As a crystalline contrast to the silos, the opening to the hotel and its lifts frames a vertical view that connects the garden and the city, leading to the rooftop rooms, restaurant, and spa. Surrounded by a panoramic terrace, these public spaces offer views of the Garonne River and Bordeaux’s historic city center.

The construction system is tailored to its functions, featuring a minimalist design of facades composed of modest concrete assemblies. The window sills are lowered to enable guests to enjoy the surrounding landscape from the comfort of their beds. The height is designed to accommodate a table and bench, creating a more functional and livable space.

The collective rooftop spaces, including terraces, suites, restaurants, and the spa, complement the architecture with their use of metal and glass materials, as well as their shed-style roofs.

The architecture conveys a sense of timelessness, seamlessly integrating with its surroundings as if it has always existed. It blends into the garden’s vegetation, vanishing behind reflections in the joinery, mirrored soffits, and the diverse functions it serves. This creates an architecture of subtlety and inconspicuousness.