Study: More Living Space Through Conversions

It’s no news that housing construction in Germany needs to be strongly supported in order to meet the demand. Now, a new study showcases an unusual approach.

Living on top of a supermarket? This could become normality. (Image:

German tenants are known to be suffering from the housing shortage. In order to counteract this, around 400,000 flats need to be finalised annually. This goal couldn’t be reached so far – not least because of vacant building land being rare in big cities. On behalf of 16 associations and organisations of the construction and real estate industry, TU Darmstadt together with the Pestel institute from Hanover developed the study “Living room potential in urban locations – increase and conversion of non-residential buildings”, which has been presented in Berlin.

Enormous potential through transformation

Already in 2016, both university and institute presented a study, in which a potential of 1.5 billion new flats has been determined through attic extensions alone. Now, this thought has been continued: The scientists discovered new opportunities for housing construction on parking houses, in vacant office buildings or on top of low-rise supermarket buildings. Without needing to create additional building land, around 1.1 million flats could be built once more – while saving on an area of up to 250 million square meters.

But not only purchasing costs for new construction land would be omitted. There wouldn’t be a need neither for shell construction, nor for extending the surrounding infrastructure. Existing supply works for water and power would only need an extension in order to connect them to the new residential units. With all these savings, such a construction project would be many times cheaper than a whole new building with the same area size.

Regulations form the biggest obstacle

As simple as this calculation might seem, the more complicated and expensive its implementation. Several regulations like for example for the construction permission, fire prevention and energy balance raise construction costs significantly. In case of too extensive modifications, grandfathering can be dropped, making elaborate retrofits necessary, which will come along with their own regulations. For example, constructing additional parking spaces could be just as necessary as the installation of new elevators, should the building surpass a certain height through its transformation. Also, residents could be bothered by this new height, since the building could now cast longer shadows – quite apart from the occurring construction noise.

However, it is not like the scientists didn’t take these obstacles into their considerations. Both obligation and responsibility for promoting new living space lie with the legislator. He has to reconsider old regulations first and foremost, like the parking space obligation. Since many people in large cities more frequently do not own a car, while staying mobile with bikes or car sharing offers, this regulation is no longer up-to-date in urban locations, according to co-author Prof. Dr. Karsten Ulrich Tichelmann.

It remains to be seen how politics and construction industry deal with these ideas. The fact that living space has to be condensed in the future is part of the urbanisation anyway – neighbours will arguably have to get used to that.

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