by Manfred Wenzel

“In terms of Baukultur, continuous adaptation to current needs offers the opportunity to rectify past mistakes and constantly formulate new qualities.” In the meantime, the technical and planning mistakes of the past have become a heavy burden on society, meaning that no one knows how to deal with them efficiently.

The new Building Culture Report 2022/23 is the most political yet.

His inner reference point is the whole tower of unresolved problems that have piled up: Climate-damaging old buildings, increasing housing shortages, expensive building codes multiplied by runaway construction price inflation, land shortages, urban traffic reversals, overburdened building authorities, social change in the city, and more. That’s tough. And it’s great that the new building culture report takes such a comprehensive look at the problems.

But does it also have a solution?

Let’s put it this way: yes, but it’s not as simple as it sounds. The recommendation for action no longer aims to “fix the mistakes of the past”, but to literally build on them, for example by adding more staff. The main recommendations for action are therefore: “Make restructuring the new guiding principle! … A paradigm shift towards a new culture of restructuring.”

The preservation of existing buildings is thus becoming the central perspective of urban development. In addition to “soft” arguments, the energy advantage is decisive: the existing buildings contain high energy costs. By converting, renovating and adding storeys, this becomes “golden energy”. The term is reminiscent of the sales slogans used by political parties in recent years. In any case, the “Golden Energy Act” would not be far away. Did the authors have something like this in mind?

Remodeling is an old subject.

Around 80 percent of construction activity takes place in existing buildings – converting, renovating, saving, revitalizing, energy-efficient refurbishment. This has always been common practice. Nevertheless, politicians immediately embraced the new model. On February 20, for example, we read that Federal Environment Minister Steffi Lemke and Federal Building Minister Klara Geywitz now want to renovate more existing homes “to combat the climate crisis and resource scarcity.”

Strange: thermal insulation, more economical heating systems etc. have usually been required for a long time and have been a condition for KfW promotional loans for decades. If politicians suddenly had the inspiration to raise more funds for this, nobody would object. However, this would not require a “new mission statement”. After all, the reason why the refurbishment targets have not been achieved so far is because the amount of funding has never matched the announced targets. But there is more to come:

The building stock must be better preserved,” Lemke said in Berlin on Monday. This would save construction costs and waste and thus help protect the climate. Together with the Federal Ministry of Construction, she wants to fight the housing shortage in an ecological way.”

This statement is only seemingly confused. It refers to the required paradigm shift and the concept of “golden energy”: building itself pollutes the climate and the environment due to its high material and energy consumption, is too expensive, changes familiar living spaces and often consumes additional urban space. Therefore, The report proclaims new construction as the political opponent of building culture. Only rebuilding would then be the salvation: no additional land consumption, no (or much less) concrete, no major urban change, no destruction of energy and materials already used.

What’s the catch in the logic?

In construction practice and with the rapidly increasing demand for residential units. As mentioned, it’s not that simple. Conversion is much more complex, difficult and risky than new construction. The report itself states under “Structural obstacles” that the existing building stock is “a great unknown”, which is why “after examining the existing building stock, preference is often given to demolition and subsequent new construction”. It continues: “Fear of the unforeseen, the associated longer construction time and rising costs that can no longer be estimated are common, especially in the case of conversions.”

We think this is exactly right. And as everyone knows: Federal Building Minister Geywitz is under a lot of pressure when it comes to the issue of 400,000 new homes per year. 2022? Missed the target. 2023 and 2024? Will be even worse. The new model will change little or nothing. Geywitz is grasping at a cheap straw and has no idea how expensive it can be.

Building practice is and remains the bottleneck.

For example, if we wanted to demolish less, architects and construction managers would have to be trained to do so. Conversion and revitalization require special skills and a lot of experience with building fabric and construction. None of this is taught in universities. Even the measuring system of a renovation project is different from that of a new building. Digital tools are of little use here. A good renovation architect must be able to “read” buildings, to foresee the complexity of a renovation and to solve it in cooperation with experienced companies. This is usually not easy, not fast, not cheap. Does anyone remember why the “construction tycoon” Schneider had to defraud the Deutsche Bank? Because his conversion projects in Leipzig swallowed up a huge amount of money and were basically not economically viable.

When we started proposing renovations instead of demolitions 30 years ago, people asked us if we were crazy.

Demolishing and rebuilding would be a) more economical, b) faster and would c) enable higher quality. In fact, this is sometimes true. And sometimes wrong. Experienced architects often see more sensible conversion potential than investors. In this respect, we think it’s a good idea to include sustainability efficiency in decisions to a greater extent than in the past and, in cases of doubt, to force investors to think a little more carefully.

In order to improve the cost-effectiveness of renovations and extensions, the report proposes something that would cost nothing apart from compromising on quality, namely special exemptions under building law: “If existing buildings were assessed according to the technical requirements at the time of their construction, this would make conversions much easier.” This would mean that in future it would be permissible to reduce the quality of construction for additional living space created in existing buildings.

We assume that many will get on board the conversion train.

However, politicians will soon realize that the new model does not automatically solve any problems. On the one hand, it will not achieve its housing construction targets. On the other hand, it could be noticed that there is a huge maintenance backlog in local authorities, and not just in schools.

If you want to promote the transition to a more sustainable building stock, perhaps the most sensible thing would be a TÜV for buildings, which would be implemented by the enforcement authority in the same way as the special building inspection. This would contribute to a completely different assessment of the real estate stock. The maintenance backlog in society – among both private and public owners – would become more visible. At present, only the bare essentials are usually repaired and otherwise wear and tear and ecological backwardness are accepted. This also does not correspond to a sensible sustainability economy. Anyone who wants to preserve building fabric so that it can be used for as long as possible and does not have to be rebuilt must not stand by and watch buildings rust and deteriorate.


There is no easy path to a climate-neutral future for cities and sustainable construction. The paradigm shift to a new culture of conversion is not as simple and cheap as it sounds. And it is unlikely to bring about the necessary changes. A normative preference for building in existing buildings is not a sufficient concept when you look at the need for improvement in cities as a whole. And urban development per se is never anything other than “building within the existing fabric”, whether you are revitalizing a building or integrating a new building into an ensemble. We therefore believe that building culture is indivisible – maintenance culture, conversion culture and new-build culture necessarily belong together.