An interview with Carmen Duplantier Flexible and Sustainable Urban Development

Reviving town and city centres to fight the doughnut effect
Reviving town and city centres to fight the doughnut effect | Photo (detail): © Lena Kronenbürger

Why does the “doughnut effect” worry architects in Germany and France? And what will the schools of the future look like? Carmen Duplantier, an architect and research fellow in the Sustainable Urbanism Department at the Technical University of Munich, talks about reviving abandoned town centres and designing sustainable houses.

By Lena Kronenbürger

Carmen Duplantier, you work on the theory of architecture in the Department of Sustainable Urbanism at the TU Munich and on the practice of architecture at your own firm. To what extent are these two activities mutually complementary and enriching?

In recent years, I’ve taken part in several competitions for the revival of town centres. I’ve increasingly noticed that I like to think outside the box and, above all, would like to gain a more in-depth understanding of the theory behind certain sustainable concepts. I'm not the only active practitioner in the department, there are other architects and urban planners working there too. So there’s always a great interdisciplinary exchange going on there.

What does it mean in concrete terms to revive a town centre?

It's a matter of making towns and village centres more lively and attractive again. One very good example is Freyung, a town in Lower Bavaria. There were a lot of vacant premises in the centre of town and no more activities offered there. More and more people had moved from the centre to the outskirts. That’s what known as the “doughnut effect”. In France, you often find these “voids” in medium-sized towns, which is why the Cœur de Ville initiative has been launched there to revitalize towns like Libourne, for instance. In Freyung, Olaf Heinrich, a young, dynamic mayor, eventually decided to declare war on the doughnut effect. When supermarkets wanted to use premises outside the town centre, he told them, “If you want to open here, then only in the town centre.” Many people were sceptical at first, but the town developed a solid holistic concept, especially with regard to transport, housing and cultural facilities.

Given the importance of collective activities, does sustainable architecture mean recognizing people as social beings?

Yes, because acting sustainably means assigning a great deal of importance to the social component, without of course losing sight of environmental and economic considerations. We always need to strike a fine-tuned balance between these three components.

You’re originally from Bordeaux and now live in Munich. What do you like about the city?

It has a very high quality of life. There are plenty of open green spaces. Munich is also polycentric, every neighbourhood is lively. I still remember how impressed I was the first time I rode my bike along the Isar. Without having to go past industrial estates, without even realizing you’re leaving the city, you just keep going – as if riding through a “green corridor”. That was a terrific sensation! Before that I was living in Paris and, though I like Paris a lot, I often felt cramped there. But Munich has some major challenges to face as well: there’s a large influx of people, so the city keeps building more and more. Consequently, the question is how to increase density without sacrificing the quality of life here. The average living space per person here is very large compared to other cities. Increasing housing density isn’t just a matter of building more densely, we should also think about how to get by with less living space.

What contribution does architecture need to make in response to the urgent global environmental issues we face?

We’re currently facing a formidable challenge. Generally speaking, the building industries have a major – and often, unfortunately, adverse – impact on the environment. So a lot has to change there! It’s important for buildings to be well insulated and energy-efficient. Furthermore, we should use more sustainable and local materials, even if they cost more. That’s an investment that simply needs to be made. Cities have expanded over the years, partly because people want to build single-family houses. That means sealing the soil over large surfaces, which is responsible for the destruction of natural areas. We should be moving back towards the centre instead. Not only that, but the increased traffic is a problem we mustn’t underestimate. This is why it’s important to create mixed-use central areas. In concrete terms, we should create urban neighbourhoods for people to both live and work in.  

You’re in the early stages of planning a building. How do you go about designing a sustainable building?
My first question would be whether it’s in a sustainable location: is the site already developed? Does it need new infrastructure? The next step is to look at the local architectural culture: What shape are the roofs? What materials were used to build the houses there? Are there any local materials we can use? I think it’s very important to respect the existing built environment. Will the new house harmonize with the street’s existing aesthetic or form a jarring contrast? I’m not in favour of artificially doing up houses to make them look old. You can build in a modern style and still adapt to the built environment. I also really like working with the existing elements of a given site. If there’s a beautiful tree on the property, for instance, I see it as an opportunity and integrate the tree into the overall picture of the new premises. Orientation – in other words, which direction the various parts of a house are facing, especially in terms of the sun – is also essential to designing a sustainable building. In our latitudes, windows facing south should be larger in order to save energy. Last but not least, flexibility is a key aspect of sustainability.
How can a house be designed flexibly?
In thirty years, a given house will be used differently from the way it is now. If you have two children, you need two rooms. But when the children grow up and move out, you can rent out the vacant rooms, for example. You have to consider questions of age, too. Will the residents eventually need a lift or is a bedroom on the ground floor already planned for later on? This is an example of very individual use, but there are other kinds of examples. We keep building underground car parks, but whether we’ll still be using as many cars in fifty years as we do today is questionable. In my opinion, garages ought to be built with more headroom so they won’t have to be demolished later, but can be used for other purposes.
Does architecture adapt to people or do people adapt to architecture?

Architecture should always adapt to people because it is made for them.

But what about HLM, social housing in France?

The idea, which was inspired by Le Corbusier, was that if you build vertically, you need to create lots of open spaces – to safeguard air quality, among other things. But in France, too many of these housing projects have been built and too many people from the city centres crammed into them. That wasn’t the ideal solution. The problem was partly due to zoning, i.e. the creation of mono-functional areas with increased traffic. In the 20th century, for instance, commercial and industrial areas developed outside city centres, far away from residential areas. Nowadays, urban planners try to avoid this zoning and to mix uses and social strata instead.
So you advocate long-term planning.

Yes, definitely. I think we in Europe, unlike the US, have a feel for architectural culture and usually know when it’s important to, say, restore a building rather than tear it down.

Are there differences between the ways Germany and France dealt with the destruction after World War II?

What struck me when I moved from France to Germany was that reconstruction was handled very differently in Germany. When a neighbourhood was destroyed in France, it was rebuilt from scratch, like the centre of Le Havre, for example. When a neighbourhood was destroyed in Germany, it was often rebuilt exactly as it was before, like the centre of Munich, for example, or the palace in Karlsruhe, which was faithfully reconstructed according to old photos and plans. Certain buildings may provide orientation for a city, so it might have been easier for the city of Karlsruhe to find its identity again through exact reconstruction. How Notre Dame is to be rebuilt is, of course, a very topical debate. There’s heated controversy between proponents of rapid reconstruction and those who favour taking time to think carefully about how to rebuild it. 

You work on both German and French projects. Is there a difference between working in Germany or France?

Architectural practice is freer and more audacious in France than in Germany, especially in the design phase. German architects have a lot more responsibility, on the other hand, because they have to work on more phases than their French counterparts. Construction generally costs a lot more in Germany than in France, but is often of higher quality. People spend a lot more money on building a house or a new school. The projects also take much longer than in France.

Are schools designed differently in the two countries?

Schools in France, as in Germany, generally consist of classrooms, long corridors and an enclosed schoolyard. But a new concept has now been developed in Bavaria: so-called Lernhäuser (“learning houses”), in which the schoolyard is not the closed courtyard we’re familiar with, but a garden, an open park. In these Lernhäuser, classrooms for first-, second-, third- and fourth-graders are placed around a multi-purpose room with a patio or atrium. There are several such clusters in the school building, each containing various age groups learning in “their own house”. You have these small units even in a very large school. This model is sustainable too, for its modular system can be expanded whenever necessary and is consequently highly flexible.