The spacious loft on the ground floor of a commercial rear building in Berlin-Kreuzberg is located on the premises of a former car repair shop. Together with the owner a generous living and working environment has been created, yielding an atmosphere that is determined by the choice of materials but also by technically complex and sophisticated measures such as underfloor heating and an acoustic ceiling. Both of these interventions go visually unnoticed, but have a big impact on the sense of well-being. In order to build separate areas for the kitchen and the bathroom (including a sauna) the former workshop has been divided in height, creating space on the upper level for a workspace and a media lounge. A large solid brick step morphing into a big open fireplace acts as a space-forming element. All fixtures in this area have a subtle appearance suggesting that they have always been part of the building. Bedroom and bathroom form a spatial unit which surface has been covered with concrete using a special spatula technique and is illuminated through internal windows and glass elements. The children's room and study are located in the side wing. The desire for sufficient storage space for the family of four was met through various built-in cupboards and cabinets with linoleum surfaces and timber elements. The materials used were coordinated in great detail with the owner. The spectrum ranges from cement tiles with graphic ornaments, manufactured steel glass walls to a large number of custom-designed and manufactured built-in furniture. The conversion of a car workshop to a residential loft may not be particularly innovative, but in this case particularly tricky. High requirements came into play, specifically in terms of the amenity value regarding heating and room acoustics while maintaining the character of the former workshop in the long-run. Great emphasis has been placed on an acoustic ceiling that is not recognisable as such, but still ensures excellent room acoustics, and the technically high challenging installation of the screed floor with integrated heating. A high level of creativity had to be demonstrated in order to organise a space that works well for a family of four, but also fulfills their desire for an open layout. Potential space under the stairs has been utilised for the kitchen, a media platform has been organised above the kitchen as well as a workstation that sits atop like an aerie with a perfect view of the living room. The new elements needed to achieve partition of space have been designed not be recognizable as newly built structures, such as the brick step, the open fireplace and the steel glass wall to the bedroom. The bathroom has been provided with daylight through various glass openings, the toilet has been given a glass lid. The access concept is also creative: in addition to the main entrance, there is a shortcut from the master bedroom through the bathroom and closet to the children's room area. Furthermore, it has been possible to integrate a small guest room and an adjoining bathroom equipped with a sauna. Primarily sustainable materials were used for the redesign of the car workshop, such as reclaimed bricks, untreated steel and concrete filler for wet areas. We were also able to stick to our maxim of "no plastic" with this building project.