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About Urban Development in Frankfurt am Main

Architect Stefan Forster in Conversation

Stefan Forster founded the Frankfurt-based architectural firm Stefan Forster GmbH over thirty years ago. Together with his partner Florian Kraft and now around 60 employees, he actively follows and shapes urban development throughout Germany. His work focuses primarily on residential construction, the conversion of office and administrative buildings, and the transformation of settlement structures.

One of Stefan Forster‘s current projects is the redevelopment of the Platensiedlung in the north of Frankfurt. The neighborhood is to be revitalized and urban living promoted with the establishment of stores, medical practices, cafés and daycare centers.

SKYLINE ATLAS met the architect and spoke with him about Frankfurt’s urban development, new building trends, the challenges of the Corona pandemic for residential construction, and the topics of sustainability and resource conservation.


“Sometimes I get the feeling that we have forgotten what a decent square looks like and is designed to look like.”

– Stefan Forster

SKYLINE ATLAS: Dear Stefan Forster, thank you very much for taking the time to talk to SKYLINE ATLAS today. More than 30 years ago, you founded your own architectural firm, which today is one of the leading offices in the field of residential construction with around 60 employees. The past decades have been marked by a significant reurbanization, as a result of which many neighborhoods close to the city center have been upgraded. Why is living in the city so attractive again?

Stefan Forster: Architects tend to glorify the renaissance of the city. But the run on cities has little to do with a longing for urban culture. Real urban development is determined by other factors. For example, the transformation from an industrial to a service society, which is accompanied by an ever-increasing concentration of jobs in cities. The education revolution since the 1970s has had a similar effect. Today, more than 50 percent of an age group study at universities and colleges. And these are predominantly located in cities. So are the skilled labor markets that are springing up around them. The changing role of women also plays a role, of course. The suburban model of life, with a male sole breadwinner and a woman taking care of the kids at home, simply no longer fits today’s lifestyles. So the attractiveness of cities has to do primarily with long-term social changes. With their infrastructure and networks. But that says nothing about how livable the city is on a day-to-day basis. In my view, strong growth that has not been managed in terms of urban development has actually made many cities less attractive.


SKYLINE ATLAS: With your architectural practice, you deal primarily with residential construction. What are the biggest challenges today for newly emerging urban neighborhoods?

Stefan Forster: The biggest challenge today is to build something like a neighborhood at all. Like the terms “courtyards” or “park,” “neighborhood” is used by investors as a marketing term. This gives even the most loveless project a positive veneer. One comes closer to the original meaning of a neighborhood if one thinks, for example, of the “Latin Quarter” in Paris. Here, young and old people from different social milieus and different origins live together. However, the mixture of living, working and culture – we also speak of a primary functional mixture – is not an end in itself, but enables a lively public space with a variety of activities. Certainly, a neighborhood does not always have to offer the buzzing street life of the “Latin Quarter,” but without a social and functional mix, without urban density and a public space worthy of the name, the neighborhood as a social space and neighborhood is doomed to failure. All that remains is a territorial unit without quality: larger than a house, smaller than a neighborhood.

The Philosophicum in Frankfurt am Main


Lyoner Straße 01 in Frankfurt Niederrad

SKYLINE ATLAS: Your competition design for the new Hellerhöfe district in Frankfurt included intensively greened inner courtyards. How important will inner-city greening be in the future and what do you think of green roofs and facades?

Stefan Forster: Green spaces can be the assets of urban development under certain conditions. These conditions include that they are designed in a way that is meaningful and of high quality in terms of urban development. Green space can offer recreation and diversion, but it can also be desolate residual space. It is therefore important to integrate parks functionally into the urban space and to treat trees as an urban design element. Urban space and microclimate must be thought of together. Extensive green roofs can contribute to this. They are relatively inexpensive, require little maintenance and allow rainwater to evaporate. Compared to gravel roofs, they also radiate significantly less heat and thus counteract the heat island effect in densely built-up cities. However, the hype surrounding green facades is not justified. Construction costs are high, and maintenance is time-consuming. Intensive facade greening can actually only be realized with luxury apartments, see the “Bosco Verticale” in Milan. Moreover, the ecological effect can hardly be measured. The little CO2 that can be stored in the plants is released again through the consumption of resources in structural engineering and trellis construction. And the facade is also destroyed in the process. I am very surprised that the current Roman coalition is betting so heavily on this horse in its climate strategy.

SKYLINE ATLAS: With Ruby Tower and Lyoner Strasse 01, you have converted two former office towers in Niederrad into modern residential towers. How can the transformation of an office city into a new urban residential district succeed?

Stefan Forster: In general, the transformation of office cities into residential neighborhoods is only possible if the urban structure is massively changed. If we look at the former office city of Niederrad, we first see an autistic collection of office towers and solitaires that form no urban context. Huge gaps gape between the buildings. Dead space that is sometimes parking space, sometimes residual space. Even after more than ten years of gradual conversion into the “Lyon Quarter,” the urban structure still conforms to the principles of a car-oriented city. Movement on foot or by bicycle is hardly possible. How will urban life ever develop here? In my opinion, the basic mistake is to leave urban development ultimately to investors. But they only develop individual projects – selectively and unconnected to the city as a whole. The result is office complexes standing next to residential complexes. Such a coarse-grained “mix of uses” is actually a paradox. It would be more correct to speak of small-scale segregation (laughs). The possibilities of architecture as the lowest level of planning are unfortunately limited here. In the course of converting Ruby Tower or Lyoner Strasse 03, we at least tried to flank an existing building with two new buildings to accommodate additional living space and the neighborhood garage. The buildings are arranged to create differentiated spaces in between – public and communal.

The Ruby Tower in Frankfurt am Main

SKYLINE ATLAS: In the wake of the Corona pandemic, the trend toward home offices has been significantly advanced. The home and workplace seem to be merging more and more in the process. What influence does this have on the architectural planning of future residential buildings?

Stefan Forster: Under pandemic conditions, we have seen that working from home – especially when both parents are employed and are expected to care for children at the same time – can be extremely stressful and conflictual. However, this will return to normal after the pandemic. I don’t think the home office will replace office work, but at best supplement it. For economic reasons alone, this will hardly lead to any changes in the requirements for housing. A permanent study, for example, would increase the size of apartments by at least ten square meters. And the urban housing markets are already tight at the moment anyway. In this respect, I see the prospects for the home office more in the dual use of rooms and in flexible furniture, for example in the bedroom.

Interior photo of the Sonnemannstraße housing project

SKYLINE ATLAS: Recently, more and more residential high-rises or so-called hybrid high-rises with multifunctional use have been built. Examples of this are the Grand Tower, the EDEN Tower or the Omni Tower. What do you think of this trend and would such projects also be an option for your architectural office?

Stefan Forster: The boom in high-rise residential buildings in some cities – above all Frankfurt and Berlin – has masked the structural problems of this type of building in recent years. Compared to conventional residential construction, building costs are much higher, so high-rise residential buildings can only serve the absolute top segment of the real estate market. Many showcase projects such as the Grand Tower or the Henninger Tower are primarily speculative objects. Their contribution to solving the housing crisis is clearly negative. In addition, they often contribute to the social segregation of the surrounding area through gentrification effects. Prudent urban planners such as Jan Gehl have been pointing out for years that the relationship of residents to the urban space is lost above a certain height. High-rise residential buildings thus lead to anonymous residents in an anonymous city – even if the high-rise residential building is “hybrid”, i.e. combined with other uses. Here, one should always ask what the goal of this mix of uses is, and that can really only lie in a lively public space. But if the functions of the public space – keyword “city in the city” – are arranged within the building, this ultimately leads to the privatization of the urban space. Indeed, that is precisely the promise of these hybrid high-rises: working, living, exercising, shopping and relaxing – all without leaving the building.


SKYLINE ATLAS: In our interview, Christoph Mäckler talked about the fact that a mix of uses and multifunctionality are the be-all and end-all of successful architecture. How is it possible that, despite this, such monotonous districts as Frankfurt’s Europaviertel are being created, and what does it take to fill this district with new life?

Stefan Forster: Quite simply, the monotony of the Europaviertel follows the specifications of the development plan. It is nothing more than applied building law. If you stand in front of the “Skyline Plaza” shopping center and look west into Europaallee, you see nothing but apartments for a kilometer on the left and nothing but offices for a kilometer on the right. Such a street naturally disintegrates functionally into two activities and can never become an urban boulevard. It also breaks down in terms of design: the facades of the offices are predominantly dark, those of the residential buildings light. In the Europaviertel, our inability to create livable cities is shown as in a burning glass. In addition to the lack of a mix of uses – which also includes the shopping center, which presents itself to the outside world in a completely forbidding manner – the lack of networking with the neighboring neighborhoods also plays a role. Just take a look at the northern border of the Europaviertel: There are virtually no connections along the Messe, to the Kuhwaldsiedlung and to the Rebstock. Instead, the border is formed by fences, walls and mounds. It would also be possible to make a central exhibition center permeable and integrate it into the city. The Basel trade fair center is showing the way.

In the Europaviertel, our inability to create livable cities is shown like in a burning glass.

– Stefan Forster


The Europa-Allee in the Frankfurter Europaviertel

SKYLINE ATLAS: In the wake of the Corona pandemic, the trend of online retailing has increased significantly. More and more frequently, you read about store closures or even the threat of German city centers becoming deserted. What contribution can architecture make to making our city centers more attractive again?

Stefan Forster: We must not forget that the decline of city centers began long before the boom in online retailing. Shopping centers – whether in the city or on greenfield sites – outlet centers or the so-called business improvement districts have been pushed nationwide since the 1990s. Now this concentration of stationary retail is falling on our feet. The Zeil is the best example: It is actually a kind of open-air shopping center – with the well-known consequences. Over the years, the parallel streets have degenerated into mere service roads, such as Stephanstraße or Holzgraben. At the same time, thousands of parking spaces have been built around the Zeil. As a result, traffic congestion in the entire city center has continued to increase. On Saturday afternoons, the Zeil is overcrowded; after closing time, it becomes a ghost town. And at night, there is always latent aggression because the necessary social control is lacking. Added to this are urban planning problems. The gastronomy should actually be integrated into the pedestal zones of the buildings so that they are enlivened – instead, one dreary shop window follows the next. In addition, the gastronomy with its pavilion boxes blocks the central lines of sight in the middle of the street, and their black mirror glass makes them look as if they were actually closed, even during opening hours. On top of that, there is the online trade. However, I also see an opportunity in this. The existing overcapacities and concentrations of brick-and-mortar retail can be reduced and the city centers can be transformed into metropolitan districts. It is imperative that city centers once again become places that are literally inhabited by people. The remaining stationary retail can then be organized along lively neighborhood streets in such a way that it once again becomes capable of communicating with the public space. For the Zeil, this would mean: less shopping, targeted conversion of individual buildings into residential space, retail and gastronomy in smaller units on the first floor, and a street profile that ties in with the Fressgass. Incidentally, the discussion of reopening the Zeil to car traffic – especially in view of the Fressgass – is completely backward-looking.


SKYLINE ATLAS: In Frankfurt, you keep coming across lifeless squares with little quality of stay. Yet this is precisely the space where public life, social mixing and social participation can take place. Are our politicians and urban planners not sufficiently aware of the importance of such squares?

Stefan Forster: I think we are dealing with a multiple crisis. Urban policy has no sense of the importance of well-designed streets and squares. It neither develops viable visions for the city, nor does it prevent public space from being privatized by companies with aggressive outdoor advertising and pointless large-scale events, and littered by haphazardly parked rental bikes and e-scooters. In addition, there is misguided civic engagement – from the “Grüne Lunge” in the Nordend to various urban gardening projects. But we architects and planners also have a responsibility for the state of public spaces. Too many in our guild unfortunately confuse urban design with surface sealing. Sometimes I get the feeling that we have forgotten what a sensible square looks like and how to design it.


The Konstablerwache in the city center of Frankfurt am Main

SKYLINE ATLAS: Next to the new FAZ Tower in Frankfurt’s Europaviertel, the Timber Pioneer, a six-story building in wood hybrid construction, is currently under construction. In Hamburg and Berlin, real high-rise buildings of this type are even planned. How do you think this trend will develop?

Stefan Forster: Every few years, a new trend is bandied about in the German debate that is propagated as a panacea. So now timber construction is supposed to fix it. Don’t get me wrong, wood can certainly make a contribution here and there – but not for every building task and for every type of building. Particularly since wood has its own problems: it has well-known structural-physical problems, it does not store heat, and its sustainability depends heavily on where we get our wood from. For the foreseeable future, we will continue to need building materials such as concrete or Poroton, but their production must of course become more climate-friendly. With regard to the carbon footprint, regional production also plays a role for materials such as clinker.


The construction site of the Timber Pioneer

SKYLINE ATLAS: Let’s venture a look into the future. What do you think Frankfurt will look like in 20 years? What will be the challenges?

Stefan Forster: As far as Frankfurt is concerned, I am somewhat pessimistic – or let’s say perplexed. Unlike Copenhagen, Vienna or Paris, for example, Frankfurt has failed to boldly tackle the necessary transformation over the past 20 years. Instead of pushing the switch to bicycles and public transportation, the density of cars has continued to increase year after year – also in terms of the number of cars per 100,000 inhabitants. From Nordend to Gallus, the effects of this policy can be seen on every corner: The car has completely colonized public spaces. Intersections, sidewalks, green spaces or front gardens are being converted into parking lots everywhere. I’m surprised that people accept this so readily. And I’m also surprised that the city’s politicians still don’t want to develop a real plan for a different traffic policy – after all, the Grünen have been in government for over 20 years. This conceptual void is then filled with project-related actionism. Following the same pattern, the Hauptwache was already closed to car traffic more than ten years ago, only unfortunately without any urban planning idea of what should happen to the asphalt area that was created as a result. But to end with a positive vision: Frankfurt should take an example from the mayor of Paris, Anne Hidalgo. She has developed clear, easy-to-communicate ideas like the 15-minute city. For years, two percent of parking spaces in the city have been eliminated every year – replaced by the Vélib rental bike system, which is well integrated into the urban environment, by benches or wider sidewalks. For Frankfurt‘s urban policy, however, the greatest challenge is to finally replace thinking in terms of micro-projects with a well thought-out policy and, above all, to want to redesign the city.

SKYLINE ATLAS: Dear Mr. Forster, thank you very much for the interview.


About Stefan Forster

Stefan Forster founded the office Stefan Forster Architekten in Darmstadt in 1989, and has been based in Frankfurt am Main since 1995. He studied architecture in Berlin and Venice and, together with his partner Florian Kraft and the team of around 60 architects, is today one of the leading residential architects in Germany. The spectrum ranges from high-quality apartments to affordable rental apartments and townhouses to large blocks. In addition, the conversion of office and administrative buildings as well as the transformation of settlement structures are among the office’s focal points. Clients include municipal building societies and cooperatives as well as private investors and developers. The office’s range of services includes object planning in service phases 1-5, general planning as well as BIM management and overall BIM coordination. The service phases 6-9, the basic evaluation as well as the cost and schedule planning are offered by the subsidiary Stefan Forster Baumanagement.


Stefan Forster