A mother and her daughter's family wanted to live together under one roof—in two distinctly separate, self-sufficient homes while preserving the freedom to support one another and enjoy their intergenerational bond. Grosche Burgmer Isensee, an architectural practice from the Bergisches Land, designed a sustainable timber structure on a sloping site in Bonn-Ückesdorf that seamlessly merges interior and exterior spaces, offering both residential units sweeping views toward Venusberg and the Siebengebirge mountains.

The primary challenge was creating distinct entrance areas and independent garden access for each residence. By staggering the units, the architects achieved separate outdoor spaces and entries—each shielded from the elements and outside views. From the street, the building reads as a unified composition; from the garden side, its dual nature becomes apparent. Each unit unfolds across multiple levels, with the family residence also claiming the basement level. Both spaces flow generously onto a spacious garden terrace, partially sheltered by upper-floor overhangs. Floor-to-floor daylight penetrates through roof openings and expansive façade glazing, creating luminous air spaces around the stairs and galleries that visually connect the levels. As a timber structure, the building functions as an effective carbon sink. Load-bearing walls employ timber-frame construction with cellulose insulation, while partition walls, ceilings, and roof elements use glued laminated timber for superior acoustic performance. Selected interior elements remain exposed to harness wood's natural climate-regulating properties and minimize finishing materials. The façade is predominantly timber, clad in horizontal pre-greyed silver fir boards. Wooden window frames, metal components, and panel details echo the façade's natural grey palette. Passive solar control comes from structural overhangs; active protection is provided by external blinds and textile shades. A geothermal system delivers efficient heating and cooling year-round.

www.grosche-burgmer-isensee.de

Photography:
Natalie Bothur
www.nataliebothur.de

(Published in CUBE Cologne Bonn 04|24)