The urban planning specification of the L-shaped building and the diverse spatial program were challenging: 74 apartments between 39 and 115 m² on 6 upper floors including maisonette apartments, special types of living & working, office space and a two-storey kindergarten. The design solves this complex task with three interlocking elements. The children’s playground could only be accommodated on the roof. PV elements are now a matter of course. Access via a single staircase with adjoining communal spaces that promote social interaction has proven to be cost-saving. The parking spaces are located in the neighboring parking garage. Attractive open spaces are provided by a spacious garden area for the kindergarten as well as private balconies and loggias. Green meeting areas with trees and a lively material and color concept contribute to the desired “inner urbanity”. The primary architectural means of achieving this is a diversity of design that is intended to create a sense of identification with the residential building and a high level of residential satisfaction, as well as meeting the important requirement of Viennese residential construction for “social sustainability”. The result is a sustainable building ensemble that meets modern living, working and community requirements in the city and is only possible in this quality through optimal cooperation with an open-minded property developer.