Green Crown Of Frankfurt-Nordweststadt: Reactivating Post-War Housing Through Collective Space And Energy Retrofit | Masters Design Project

Site Context

The project is located at Gerhard-Hauptmann-Ring 266–272 in Nordweststadt, Frankfurt am Main, a post-war residential district characterized by modernist planning principles, repetitive housing blocks, and generous green open spaces. The existing building is a linear social housing block composed of four cubic volumes with flat roofs, typical for the area’s rational and economical construction logic. While the neighborhood benefits from greenery and good infrastructure, the housing stock faces challenges related to energy performance, spatial rigidity, and changing living patterns, especially the growing need for home-office spaces and shared community areas.

The intervention focuses on the rooftop as an underused spatial and energetic resource. By extending the building vertically, the project introduces new collective and semi-private programs without altering the existing apartments. The added level accommodates shared working spaces, flexible communal kitchens, and transitional half-open zones that function as social condensers. At the same time, the rooftop extension acts as a climatic buffer and energy-enhancing layer, improving the building’s overall performance while reinforcing community life within the Nordweststadt residential fabric.

Design Process

A new construction was designed on top of the building, using the existing flat roof and changing it into liveable space. Firstly, construction would require breaking the ceiling above the staircase and insulating the rest of it properly. Later on, each staircase would be enlarged to one additional floor with lightweight timber frame construction. The stairs to the rooftop would be made of steel elements easily joined to each other, which would make this construction phase really quick. After that, modular timber frame construction would be built, with 2 meters distance between each frame. Next, that construction would be filled with polycarbonate sheets, which would create half-open spaces. The last phase of design would be to build fully insulated spaces that would be inside those half-open ones. They would not be too enormous but big enough to use them as working areas.

The building would not only have the purpose of fulfilling spatial requirements of residents, but its main goal would be to improve building performances. That aspect would be achieved by implementing an energy recovery system in the new construction. Half-open spaces would be filled with different kinds of plants that can help in creating a good atmosphere but would also raise temperature and humidity. This system would collect it and transform it into a renewable energy source for residents. New spaces can also work as thermal buffer zones. In winter they would work as an extra insulation layer, helping upper apartment units to maintain heat, and in summer residents could open sliding doors to increase ventilation and let a lot of fresh air in.

Final Outcome

The interior would be adjustable to the resident’s needs. Most of the furniture would be moveable, which makes the kitchen, common space, and working areas really flexible. In special working rooms, which were highly required by current residents, moveable walls and furniture would allow them to fit the space to their own needs, no matter if it is a small home office or a bigger workshop for a few people.

Outer spaces would be partially left to their own to decrease maintenance costs. These areas would be changed into green roofs, but on most of them there would be just grass growing that does not require any gardening work. They could also work perfectly for younger residents, who can use it as a playground. Some spaces would be changed into orchards, where residents could grow their own plants, and others would serve as areas for solar panels, which would also improve the building’s performance.

Conclusion: Ultimately, the project reclaims the rooftop as a shared spatial and energetic resource that responds to contemporary living needs. The lightweight vertical extension introduces communal spaces while improving the building’s thermal and energy performance. In doing so, the existing post-war housing block is redefined as a flexible and sustainable framework for collective living.

[This Academic Project has been published with text and images submitted by the student]