analysis of 18 buildings from the 1960s and 1970s in Berlin City West
Bollinger+Grohmann GmbH, Berlin
Solares Bauen GmbH, Christian Neumann – Fraunhofer ISE
Holtz Gostomzyk Architekten, Berlin
The occasion for us to conduct a study was given not only by the ongoing discussion about reducing our CO2 emissions, but also, and above all, by the visible deterioration of buildings from the 1960s and 1970s, as witnessed in countless cities throughout Europe – together with the resultant high level of vacant properties.
What are the requirements for a successful renovation and what means are needed for its implementation? To find out, we sampled 18 office buildings in Berlin City West, examining them for their potential to be made usable again for a further 20–30 years through being renovated.
Why buildings from the 60s and 70s? The buildings from this period have long exceeded their first usage cycle. Furthermore, due to their often inherent utilitarian nature, they also provide a good basis for being stripped down to their load-bearing structure and thus present a starting point for developing a new idea for a further usage cycle.
As architects, what interests us is the question of how to implement quality in renovation projects. The politically motivated programmes for energy saving (Energy Performance Certificates, promotional programmes) have so far proven to be unsuitable for initiating a sustainable improvement in quality. Isolated measures, such as improving the building envelope, may even cause the opposite effect in the long-term, because, although they tie up large investments, they are ultimately insufficient for making a building become an active part of the city once again. A building that has simply been renovated in terms of its energy efficiency but is otherwise of low quality will not be in demand. There is more to a successful project than this.
The renovation of existing buildings is an important component of sustainable economic management. A renovation and the subsequent additional period of use will open up new perspectives for a building beyond its usual lifecycle of con- struction, usage and deconstruction. Buildings whose basic structure gives them possibilities for further usage are naturally more economical and therefore more attractive, since up to 40% of a building’s total value is attributable to its basic structural fabric anyway. Our study reveals various ways in which this potential can be opened up and, therefore, offers different approaches for giving a new lease of life to derelict properties.
Using differentiated analyses, the sampled reference projects were examined in terms of their surroundings and the structure of the buildings. Together with the concepts for usage that were drawn up in parallel, perspectives can then be identified on the basis of which bespoke solutions can be developed for user/target groups.
A building that previously served as pure office space does not necessarily have to be re-used in such a mono-functional manner. It is entirely possible that the potential analysis will reveal more suitable uses or user groups that will put a property in a new marketing bracket. The ideas for new contents can turn derelict buildings into completely new projects. The holistic processing can produce results that make the renovated property indistinguishable from a “new building”.
The only way of designing a tailormade solution from the complex requirements is to have an integral planning, beginning at Phase 0 (i.e. the project development phase, including analysis, target groups, usage variants) and going right through to the project realisation. All aspects (infrastructure, urbanistics, sociology, economics, engineering science, sustainability, design) play a role here through all phases of the project. It is only by networking the teamwork of the different parties involved in the project that the desired planning quality is made possible.