The ground plan of this old apartment in Berlin’s Charlottenburg was characterised by limits and crampedness: chopped-up spaces, narrow rooms and a tube-shaped corridor created a depressing feeling and let little natural light in. At the same time, the owners wanted above all friendly and airy rooms that provide ample space for guests and socialising. What has emerged is a spacious living, cooking and eating area, which – as circumstances require – can be transformed into a generous, light-filled single room with the aid of oversized double doors. These highly individual needs required boldness and heavy intervention in the historical floor plan. Yet thanks to numerous customised solutions, the old apartment now optimally meets the demands of the young owners, yet still radiates, post-overhaul, a sense of innate natural confidence.