Stumpergasse 56 was built under Vienna's Gemeindebau NEU programme: indefinite leases, capped rents and no equity contribution required make housing durably accessible, not just cheap at handover. On a small, awkward infill site, formerly home to the Institute for Advanced Studies, 46 residential units of 37,44 to 165 m² with two to five rooms were realised, each with its own outdoor space.

The mix targets young Viennese, single parents, families, couples and seniors, including a shared flat for six queer seniors. District heating, photovoltaics, external sun shading and triple-glazed windows keep running costs low for the long term. Combining social diversity, low operating costs and a central location near Mariahilfer Strasse, the project shows how affordable housing works in a dense urban setting.