Sandy: Lowering energy consumption by increasing building retrofits

Around a quarter of greenhouse gas emissions in Germany can be traced back to residential buildings. Existing buildings, therefore, offer particularly high potential when it comes to climate protection efforts. Municipalities play a special role in boosting this potential: they are familiar with the structures of the buildings, cultural factors and financial options – and have good methods of communicating with their residents. In order to support municipalities’ climate protection efforts, the “Sandy” project (the name comes from the German term “Sanierung dynamisch” meaning “dynamic retrofitting”) is investigating how retrofits to private residential buildings can be promoted and is developing corresponding measures based on the results

In the “Sandy” project, which is funded by the German Ministry of Research, the Hochschule für Gesundheit (University for health care professions) in Bochum is currently conducting a study entitled “Vom Klimaschutzkonzept zur zielgruppenorientierten Sanierungsoffensive: Strategien, Lösungsansätze und Modellbeispiele für dynamische Kommunen” (“From a climate protection concept to a target-group-oriented retrofit campaign: strategies, potential solutions and models for dynamic municipalities”). Focusing on Dortmund, Hamm and four additional partner municipalities, the project has carried out analyses and developed concepts which help to increase the number of existing buildings being retrofitted, thereby reducing energy consumption in municipalities. The Öko-Zentrum NRW is one of the top addresses for sustainable construction in the whole of Germany and provides the practical expertise for the research project. Green City Energy from Munich is another practical partner in the research team, which is coordinated by the University of Ulm, and the Karlsruhe Institute of Technology and Kassel University are also taking part.

Engine for progress:

  • Improved knowledge of problems and potential courses of action
  • Field of action with a high potential for climate protection
  • Tools for different local situations
  • Promotion of municipal development

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Photo: Heike Köckler

The possibilities for energy-efficiency retrofitting in private residential buildings range from a partial retrofit to a total retrofit. They can be combined, as shown in this photo, with urban guidelines on protected ensembles of buildings.

Knowing the obstacles to implementation

Those who make energy retrofits to their home save energy, become less dependent on rising heating costs and simultaneously increase the comfort of their home and the value of the property. Despite these benefits, the retrofit rate has been low for many years. What prevents house owners from retrofitting their homes?

Some of the obstacles have already been acknowledged: the amount of time required, which is typically quite long for extensive retrofits, may put older people off from making renovations to their homes. Likewise, high rents in areas that are growing particularly quickly and rents that are too low in areas that are rapidly losing residents also mean that fewer people are willing to carry out retrofits. However, there are other aspects which also influence the decision. These include each individual’s respective living situation, financial security, personal living prospects, the available information as well as the property’s prospects in the future – and the research therefore focused on these criteria. In light of demographic changes, special emphasis was also laid on house owners with a migration background.

A toolkit for municipalities

Together with the municipalities, the results of the surveys were discussed in detail with relevant players in the field, taking into account overall developments within society and the overarching political framework as well as the specific local conditions. Working on this basis, information, motivation and funding measures were developed into a toolkit: these tools range from general recommendations for hosting informational events, to using neighbourhood architects who serve as on-site contacts, to specific and newer approaches that have already been tested, such as ‘retrofit parties’ where a host invites those who are interested to attend a meeting with a consultant. During this process, the measures were designed so that they could be used in the wide range of different conditions found in municipalities or be adapted to these. The measures are supplemented by information regarding policy instruments that municipalities can use to influence the development from a regulatory perspective. Among other things, these include requirements, such as modernisation and renovation orders.

Photo: hsg/Volker Wiciok

“The energy-efficiency retrofitting of private residential buildings depends on many factors. It can be seen as a problem that is highly complex or even impossible to solve. Understanding this variety and complexity as a resource is the first step towards a climate-friendly future.”

Prof. Dr Heike Köckler, Hochschule für Gesundheit (University for health care professions)

Partners and sponsors

  • Hochschule für Gesundheit, Department of Community Health
  • Universität Ulm, Institut für theoretische Chemie, Wirtschaftschemie
  • Universität Kassel, Fachgebiet Ökonomie der Stadt- und Regionalentwicklung
  • Karlsruher Institut für Technologie, Fachgebiet Immobilienwirtschaft
  • Karlsruher Institut für Technologie, Deutsch-Französisches-Institut für Umweltforschung
  • Öko-Zentrum NRW GmbH
  • Green City Energy AG

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