Rethinking monument protection?

Building in existing buildings is becoming increasingly important. However, the requirements of monument preservation often present architects with challenges. As the architect Thomas Will once put it, heritage conservation negotiates the past and the future in the present. But how much future is possible in the area of conflict between preservation and use?

When Winfried Brenne began to take an interest in the preservation of modern architecture, monument protection was still in its infancy. Almost half a century has passed since then, during which the Berlin architect has repeatedly wrestled with the requirements of monument preservation. Brenne is one of the big names in this field. Together with Franz Jaschke and Fabian Brenne, he has renovated numerous icons of modernism and post-war modernism since 1990, including Walter Gropius’ Bauhaus building in Dessau, Werner Düttmann’s Akademie der Künste in Berlin and Hannes Meyer’s former ADGB Federal School in Bernau. It was an issue of the magazine of the Deutscher Werkbund, “Werk und Zeit”, which aroused Brenne’s interest in the subject of building in existing structures in 1977. Its main topic was the Berlin housing estate “Onkel Toms Hütte”, built by Bruno Taut. His architect colleague Helge Pitz, with whom he later shared an office, lived in a terraced house right there. Although the magazine focused on the socio-historical background of the estate, the two architects quickly realized the architectural significance and quality of the “Onkel Toms Hütte” estate.

Even if there was little evidence of this in the meantime: window surfaces with insulating glazing had replaced the small double box windows, while aluminum doors took the place of the original wooden doors. According to Brenne, a fundamental problem was that the new emulsion paint coatings on the existing smooth plaster at the time led to structural damage. The owners, including many private individuals, had then painted the houses with a “mouse-grey” emulsion paint.
The idea of looking at a relatively young housing estate – built between 1926 and 1931 – from a conservation perspective was still unusual at the time. It was not until 1975, the European Year of Monument Conservation, which marked the beginning of “modern” monument conservation in West Germany, that the subject gained momentum. From then on, a concept of monument was consistently applied in West Germany that understood the monument as a testimony to history and also included artifacts of industrial culture and everyday history from the 19th and 20th centuries.
In addition, a more holistic approach to the surviving built environment prevailed: The protection of ensembles became much more important and urban planning began to integrate heritage conservation objectives.
In order to find out more about the Onkel Toms Hütte estate, Brenne asked the State Monuments Office for access to the files. In Zehlendorf, he was given the key to the file room. “Unimaginable today,” Brenne states, “In Berlin in the mid-1970s, monument protection still had no basis, and today’s methodology was only slowly emerging.” The city did not receive a monument protection law until 1978.

Brenne’s initiative was to pay off: “I went through the files and found a letter from Bruno Taut to the supervisory and building police, which also contained a color plan”. The architect discovered from the construction files that the estate houses were originally painted with colorful mineral paints from the Keim company, consisting of earth pigments. “That was a big surprise,” emphasizes Brenne. “Everyone was talking about white modernism, and then we came to realize that the Waldsiedlung was polychrome.”
The Pitz-Brenne architectural workshop at the time set to work on a comprehensive survey of the modernist housing estates designed by Bruno Taut in Berlin, which later served as the basis for the restoration of the buildings in line with their listed status. To this end, the architects collected thousands of material samples.

After reunification, Berlin’s heritage conservation sector also had to reorganize itself, reports Brenne. “It was a very wild time,” he recalls. “Monument preservation was under extreme pressure after reunification.”
In 1998, his office, together with the Stuttgart-based company Transsolar Energietechnik, entered a federal competition for the conversion of the baroque arsenal of the German Historical Museum in Berlin. An initial design with suspended ceilings and raised floors for the new building technology would have so fundamentally altered the character of the building’s interior that it was rejected by the conservation authorities. In contrast, the proposal by Brenne Architekten envisaged an innovative, decentralized air conditioning system that made use of the building’s deep window recesses. After a one-year test phase, the refurbishment was carried out in accordance with the preservation order, which was praised by the then State Conservator Prof. Dr. Haspel as the “art of the smallest possible intervention”. For Brenne, this formulation sums up what needs to be done today when building in existing buildings: “Adapt the existing building to today’s uses with as little structural effort as possible – in every respect.”

Architects, clients and monument conservators do not always agree straight away: “There are also cases that lead to discussions in detail, and then you have to find ways to reach a compromise that saves the overall idea”. He has obviously succeeded in doing this very often: In 2020, Brenne was honored by the German National Committee for Monument Protection with the German Prize for Monument Protection, Karl-Friedrich-Schinkel-Ring, for his tireless struggle for such compromises.
The most important thing is to learn from the building, understand it and document it, summarizes Brenne: “Without a substantive, structured inventory, you can’t do sustainable planning.” However, it is precisely the inventory that is too often skimped on. “If this is not available, you may end up in conflict during construction”. As monument preservation has significantly higher requirements than in the past, this can lead to a cost dilemma. “Building in existing structures requires a detailed ‘search for traces’ and as objective an examination of the building’s DNA as possible,” emphasizes Brenne. After all, every building has its own specific construction with its material and technical or production-related characteristics. In addition, there are further specifics such as spatial structure, types of use and function or surfaces.

Due to climate efficiency and ever-increasing costs in the construction industry, architects today are striving for low-tech solutions and sufficiency. This was the case, for example, with the recently won competition “The Museum of the Future” for the RWTH Aachen University together with KRP Architekten.
In stark contrast to the magnificent, albeit dilapidated, façade is the small-scale interior structure. The aim of the competition team was to restore the quality of the space by minimizing interventions. In order to preserve the historic windows, a second level – clay bricks with windows like a display case – is to be used inside. Clay is an ideal building material for regulating building physics, as it absorbs moisture and releases it again. The result: low building maintenance costs, good indoor climate, little technology, no air conditioning.
The architect advocates the networking of knowledge in a database, which helps to evaluate a building in advance. “This way, the building owner or craftsman knows, for example, what building materials he will find and how they should be maintained.” What’s more, he says that heritage conservation needs to move out of its niche existence: “In recent decades, it has gathered a great deal of knowledge about existing buildings and their life cycle, which now provides important starting points for the reform of the construction industry and the building turnaround.”
All this against the background that the number of listed buildings in Germany has increased seventy-fold since 1970, and the trend is rising. However, in view of the acute construction crisis, clients and architects are increasingly finding themselves in a dilemma when it comes to finding a balance between additional monument conservation costs and proliferating, more expensive building standards.

“When you see how much breath – some builders need compared to ‘new builders’ or ‘demolishers’, more support should come from the state,” demands architect Achim Mayer from Mühlacker in a letter to the Deutsche Architektenzeitung. The magazine had asked architects about their experiences with monument protection. “The financial burden is sometimes very oppressive due to the length of the construction period and I wonder how some people cope with it.” Hamburg architect Frank Lutze also reported negative experiences, saying that he often experienced the local heritage office “not as a partner, but as an opponent”: “A definition of heritage protection based exclusively on the preservation or restoration of the original condition leads to requirements that often make the economically viable use and development of listed buildings impossible,” he reports. As a result, some monuments may be left to decay, warns Lutze.
“What happens when the much-praised processes of consideration and small-scale decisions in a functioning democratic constitutional state have to give way to ideology and monuments are classified in radical categories rather than according to their characteristics?” asks Marc Jordi, who runs an architecture firm in Berlin together with Susanne Keller. “We have experienced this ourselves using the example of the medieval episcopal church of St. Mary’s in Berlin, which has undergone many alterations, bishops, priests and Baumeisters over its 700-year history, but which, as a monument of special rank, is now no longer allowed to undergo any external changes according to the State Monuments Office,” he reports.
The Marienkirche is therefore in the same category as the Neue Nationalgalerie by Mies van der Rohe, which was built in the late 1960s – i.e. in a small time window – and can be attributed to just one author. “This prevents an adaptation to what is structurally necessary for a church and its congregation,” complains Jordi.
“So is monument protection going too far here by freezing a condition and no longer allowing any leeway, or is the monument being protected from the short-term interests of its users and thus preserving social values?” Susanne Keller also questions such rigid interpretations of monument protection. A more differentiated view on the part of monument conservation is needed, the architect believes.

At the same time, Jordi and Keller are proven advocates of monument protection: “Without it, the architectural cultural heritage would have already disappeared in many cases and many fine things in need of protection would have been swept away.” Economic aspects also speak in favor of preserving and using historical substance: “The houses, streets, roofscapes, old towns, industrial areas and village centers that are protected are the long-term economic winners due to their preserved beauty or uniqueness.”
For Keller and Jordi, enduring and mediating the conflict between often long-term social values and short-term private interests is part of the cultural task of architects. “We need to renegotiate and make monument protection more pragmatic,” Winfried Brenne also postulates. The protection of building culture is only sustainable in the long term if it can be reconciled with the interests of future use.

Read more: Anyone entering the house in the Unesco World Heritage Horseshoe Estate imagines they are in a time capsule.