Sustainable transformation is currently one of the most challenging topics, also in the construction industry. Sustainable housing must be affordable – but how? VIVID spoke to experts about solutions.

Even as a student of architecture, Prof Dr Eike Musall was interested in energy-saving construction. During his doctorate on the subject, he took part in the "Solar Decathlon Europe" student competition, which centred on the construction of a highly efficient building that covers its energy requirements exclusively with self-produced solar energy. Six years ago, he took up a professorship in the Department of Architecture at Düsseldorf University of Applied Sciences (HSD). When the "Solar Decathlon Europe 21/22" came to Wuppertal, Eike Musall applied again, this time with a team of staff and students from all seven faculties of the HSD.

‘The aim of our MIMO (Minimal Impact Maximum Output) project was to tackle the topics of energy-saving and sustainable construction with students from a scientific perspective and to build physically,’ explains Eike Musall. In the follow-up project "Living Lab NRW", funded by the state of NRW, students and test subjects live in MIMO for teaching and research purposes in order to analyse its energy efficiency and room comfort using meters installed in the house.

Participant in the workshop 'Circular Economy Material Resource – A Building Material Store for Düsseldorf', which took place in June 2024 at the Living Lab Campus NRW in Wuppertal.

Another project that has emerged from MIMO in the Department of Architecture is the "CO2Bau cooperation platform". Background: The Ministry of Culture and Science called for the formation of networks and the joint promotion and advancement of ideas in the field of sustainability. ‘In the construction industry as a whole, we are dealing with a high level of complexity and have to overcome numerous hurdles because there are many different interests. That's why we came up with the idea of turning the interdisciplinary MIMO project into a cooperation platform that identifies these obstacles, so that we can analyse and remove them together. One step is to establish a parts warehouse in the greater Düsseldorf area,’ explains Eike Musall. The aim is to store material from the demolition or conversion of buildings that would normally end up as waste so that it can later be reused in other building projects.

Prof Dr Eike Musall implemented the MIMO project with a team of staff and students from all seven faculties of the HSD. The objective: energy-saving and sustainable construction.

How does Musall assess the overall possibilities of building sustainably and cost-efficiently at the same time and thus creating affordable living space? ‘One aspect of sustainable construction is sufficiency,’ he explains. Sufficiency in construction means planning very consciously and economically, scrutinising needs and habits. ‘In Germany we live on an extremely large area of space. The question is whether we can condense our lives and live on less? What's more, in this country we are used to every cable and every pipe being laid under plaster; sound insulation and accessibility are also an issue - which not every flat necessarily has to fulfil,’ he explains. One idea in this context is the endeavours towards building type E, an innovative approach to cost-effective construction. The Federal Ministry of Housing, Urban Development and Building (BMWSB) - together with its partners from the Alliance for Affordable Housing - has set itself the goal of making housing construction simpler, faster and more efficient. Overall, there is a need for support from politicians in the form of stable and permanent funding in order to create predictability.

Sometimes, however, it is enough to scrutinise the equipment that is standard for us today. Thorsten Ehrich, founder and managing director of EHRICHarchitekten, knows that it is possible to make savings without sacrificing comfort. He has set himself the goal of developing the most economical, aesthetic and sustainable solution possible for every architectural issue. He specialises in revitalisation, conversions and listed buildings. Thorsten Ehrich has noticed that the city of Düsseldorf is very co-operative and encourages the high-quality conversion of existing buildings. More and more developers are also realising how sustainable this is. ‘With all sustainability issues, it is important to come back to simple, common sense. What am I actually asking of the environment and my surroundings? Sustainable construction is no different,’ explains Ehrich.

Thorsten Ehrich, founder and managing director of EHRICHarchitekten, knows that it is possible to save on furnishings without sacrificing comfort.

The important question is what standard you want to establish. ‘Of course, you can install the latest technology in every living space - or decide that a socket in every corner will suffice. It's about only implementing features that I actually need in order to remain cost-effective.’

When it comes to the use of materials, he also advocates an aesthetic rethink. ‘Walls don't always have to be papered. If you see rough, slightly uneven plaster in Tuscany, you find it romantic. In Germany, it's perceived as a defect.’ He is concerned with attitude – and would like to see more naturalness as a kind of counter-movement to aesthetic artificiality.

Nevertheless, the current very high property prices, which ultimately also inform the projected rents, stand in the way of affordable living space. But even here there are exceptions - such as one of Ehrich's clients, an institutional contractor, who can charge fair rents because he maintains a steady number of buildings. An example that shows how important it would be to put more housing construction back in the hands of cities and municipalities.

Ehrich also sees the "building type E" approach as having a promising future. ‘I spend a lot of time in Holland and often see that pipes and cables are not concealed. When I asked a friend why they build so cheaply here, he said that the opposite was the case and that they had therefore considered more cost-effective alternatives. The Dutch aim for a work-life balance that is different from us Germans. We often want to establish a level of comfort that we can't actually afford,’ said Thorsten Ehrich.

Cornelia Zuschke, Councillor for Planning, Building, Housing and Real Estate of the state capital Düsseldorf, blames the high prices of land and ground in particular for the fact that the cost of housing construction has skyrocketed in recent years. This is where the city wants to come in and exercise a right of first refusal on land in order to stop speculation, but also with regards to the use of its own land, e.g. in subsidiary companies or co-operation models. Zuschke also praises the generous funding programmes of the state of NRW, for example for the subsidised rental segment in both funding channels A and B, but also mentions the city's "housing impulse programme" for the middle rental segment for rented and owner-occupied flats. Another focus is on reducing bureaucracy and providing support in the approval process for conversions or extensions and working with the Chamber of Architects and its members on creative advisory services; new approaches are also being taken to identify and thus procure land for developers. Promising approaches that will get affordable housing construction underway in the state capital. And in Düsseldorf it is urgently needed! •

Words: Tom Corrinth
Pictures: PR, In-LUST, Jennifer Burgmann, In-LUST, Jennifer Burgmann, Eike Musall Privat, eam MIMO, Marvin Hillebrand, EHRICHarchitekten , Martina Ferrera, Martina Ferrera

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