A subdivided lot in an urban residential neighborhood and a revised 1960s masterplan set the parameters for this infill project. The homeowners' vision for exposed concrete architecture became the design catalyst. Baurmann Dürr Architects responded with a compact, monolithic structure featuring solid lightweight concrete exterior walls. This modern material serves dual purposes—structural support and thermal insulation—while creating a protective façade outside and a finished interior surface within. Given the site's modest footprint, a conventional multi-layer wall assembly would have consumed precious square footage. The solid walls measure 45 cm thick, a solution refined through the use of standard frame formwork to control costs. The finished surface was then treated with hydrophobic protection. The material itself becomes the building's aesthetic signature: no plaster, no paint—only the subtle, velvety texture of lightweight concrete defining the envelope. The interior walls create striking contrast: conventionally masoned, lime-plastered, and finished white.

The floor plan evolved directly from the site's constraints: the compact footprint required by infill development and the sloping terrain, which reserves the best views for the upper level. This dictated the placement of the kitchen and dining area on the top floor, where a generous roof terrace with outdoor fireplace extends the sightlines and captures panoramic views. The garden level contains the living room opening to the landscape and the master suite, while ground level houses the entry and private quarters. A single-run staircase and soaring vertical void unite all three levels spatially.

The garage nestles beneath the house as a distinct volume. Its wooden cladding has been carbonized—a process that chars the surface to weatherproof it naturally, without paint. This darkened, subtly lustrous finish dialogues beautifully with the slightly porous, soft surface of the lightweight concrete above.

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(Published in CUBE Stuttgart 01|21)