bureau de change marries stock brick and tiered concrete volumes for cast house in london

Bureau de Change builds cast house in london

Cast House is a modern, standalone residence located within a tranquil suburban enclave in Clapham, South London. Designed by Bureau de Change architects, the project pays homage to the historic charm of the neighborhood’s Edwardian houses while introducing a fresh contemporary perspective. The area is known for its distinct architectural characteristics, such as gable roofs, bay windows, layered materials, and inviting porch entrances. Cast House integrates these traits by combining London stock brick and precast concrete, resulting in a balanced facade that marries projecting windows with a recessed entrance porch.

The use of precast concrete details, reminiscent of the local architectural style from the 1930s, adds a classic touch to the structure, creating a consistent visual language. The architects chose to incorporate stacked concrete volumes on multiple levels, enhancing both the aesthetics and the connection with the landscaped garden at the rear of the property.

all images ©Gilbert McCarragher

cast house Bridges Tradition and modernity

The entrance facade of the house has been designed to blend with its historic neighbors, respecting the established rhythm of the street. In contrast, the back of the house takes a bolder approach, featuring a series of tiered cubic volumes that extend into the garden, including a sunken patio area. Both facades share a common design concept and use a simple palette of materials, mainly brick and concrete, which are used throughout the entire structure.

To maximize the available space within the constraints of the original house’s footprint and height, the design team at Bureau de Change dug below ground and added an attic room with a dormer window to create a spacious four-story, 420-square-meter house. On the rear elevation, the floors project outward as distinct boxes, allowing each room to open onto a private terrace overlooking the stepped garden terraces. This design floods the interior with ample natural light. Precast panels containing ground granulated blast-furnace slag (GGBS), a cement substitute that reduces the carbon footprint, were used in construction, to also give the concrete a textured appearance, resembling whitewash. The softer, variegated texture of the concrete is achieved through the use of additional molds at the rear, bearing the imprints of bricks, and by revealing the aggregate on the windowsills and planters through timber grinding.

the structure blends harmoniously with the Edwardian-style homes in London’s suburbs

an Interplay of Materials

The concrete volumes have undergone meticulous craftsmanship, featuring framing lintels that accentuate their structure. On the street-facing side, the brick volumes are outlined with interlocking corners, cut at an angle to create a rhythmic vertical pattern that is inverted in the concrete base below. The recessed brick detailing gives the impression that the concrete volumes have been integrated into an existing facade, effectively distinguishing between dynamic and static elements, protruding and receding features, and the juxtaposition of brick and cast concrete, highlighting the overall structure.

When it comes to the interior, the architects added a suspended staircase in a vibrant azure blue, complemented by vertical railings, which connect all floors and guide occupants to the stepped garden terrace, where natural light awaits. The terrace serves as a bridge between the garden and the house, facilitated by a concrete staircase flanked by cubic volumes housing planters and an open hearth for outdoor cooking. In terms of construction, the principles of a passive house have been adhered to, integrating two air source heat pumps (ASHP) and a mechanical ventilation heat recovery system (MVHR) to enhance energy efficiency.