Open Yet Protected
A residential building in Sülz that floods interiors with natural light and opens onto inviting outdoor spaces
The two owners initially planned only to renovate their neighboring apartment buildings in this desirable location near Cologne University Hospital. However, after achenbach architektur conducted a feasibility study, they discovered that renovation would prove both economically unfeasible and impractical with occupied buildings. A new construction emerged as the solution—one that embraces the street while respecting residents' privacy.
The two plots were consolidated to maximize lettable floor space while elevating residential quality throughout. The design prioritizes energy efficiency and a striking street presence. Without an existing development plan, the structure needed to align with neighboring buildings' heights under German building code and integrate thoughtfully into the local streetscape. The three-story design—topped with a penthouse level and anchored by underground parking—takes its conceptual cue from the cascading outdoor terraces, which flood all thirteen units with abundant daylight. The maisonettes on the upper floors, ranging from one to four rooms, maintain full privacy thanks to a clever system of perforated sheet metal sliding screens positioned in front of covered terraces and balconies. These screens offer flexible control over sightlines and shade while textile zip screens filter heat during warmer months. The symmetrical façade, centered around the main entrance, is rendered plaster punctuated by dark green glazed ceramic panels that add visual warmth and material depth at the terraces. Glass balcony railings preserve the calm, uncluttered façade while maximizing views outward. The elevator shaft is cast in textured exposed concrete, a durable and refined material presence.
The shared circulation areas—hallways and stairwell—are finished with robust marine-grade wallpaper for lasting durability. Oak parquet warms the living spaces with a welcoming character, while porcelain stoneware grounds the bathrooms. The two generous top-floor maisonettes feature integrated kitchens with premium natural stone countertops. Sustainability is woven throughout: green roofs, air-source heat pumps, and decentralized hot water systems minimize environmental impact.
Photography:
Philip Achenbach
(Featured in CUBE Cologne Bonn 03|24)
