Solar village Dormagen: Retirement home to passive house standard

In 2011, a retirement home was built to passive house standard in Dormagen. Through an ingenious choice of insulation and construction materials, not only does the building partially supply itself with energy – the owners were even able to build it more cheaply than conventional homes.

The idea came to the architect Yvonne Axler-von Berg when reading a newspaper article: An empty site next to the district hospital in Dormagen was to be developed. To her, it was the ideal location for a retirement home, which the city had needed for a long time. So she presented her idea to an expert who knew how to implement energy saving at retirement homes: Passive house expert Andreas Nordhoff from the Cologne Institute for Building and Sustainability had already built the first passive house nursing home in Europe in Mönchengladbach. Together, the two submitted a proposal and brought in CONESTA Consulting & Construction GmbH & Co. KG as an investor, who then broke ground on the new St. Katerina Retirement Home.

Engine for progress:

  • high solar coverage using seasonal heat storage
  • low energy costs thanks to the passive house standard
  • operator transfers concept to future building projects

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Photo: Axler von Berg

Through an ingenious choice of insulation and construction materials, not only does the building partially supply itself with energy – the owners were even able to build at a price that was about 16 per cent cheaper than conventional homes.

Passive House Cheaper Than Conventional Models

This resulted not only in a building that partially supplies its own energy but also one that was cheaper than those of conventional competitors: Through the ingenious selection of insulation and construction materials, the architects realised the building at a net cost of only EUR 1,050 per square metre. For comparison: A conventional retirement home in 2011 cost on average EUR 1,250 per square metre. A saving of around 16 per cent.

Minimal Heating Requirement – Low Energy Costs

The facility built to passive house standard calculated a heating requirement of 15 kilowatt-hours per square metre per year and is thus clearly below requirements set out in the currently valid Energy Conservation Ordinance (EnEV 2009), which limits calculated consumption to 65 kilowatt-hours per square metre per year. Furthermore, solar thermal systems support the hot water supply: In the summer period, any excess heat is stored in a seasonal water storage tank – a "heat sink" under the floor. By the end of the summer, the temperature of the storage tank has risen to 22-24 degrees Celsius (°C). This reduces heat loss through the floor in winter.

Operator Applies Concept to Other Nursing Homes

Investor and operator have been convinced by the energy and economic benefits of the building. Malteser Rhein-Ruhr gGmbH also wants to apply the passive house standard to further projects in the future. A second home has already been built to this standard in Drensteinfurt in the Münsterland region. The St. Katharina Retirement Home is one of the solar housing developments recognised by EnergieAgentur.NRW. At the end of the 1990s, the state government launched the project called „Mit der Sonne bauen – 50 Solarsiedlungen in NRW“ ("Building with the Sun - 50 Solar Housing Developments in NRW"), which is coordinated by EnergieAgentur.NRW.

Photo: Foto: Axler-von Berg

"St. Katharina contributes to improving the climate in the Neuss energy district with its resource-conserving design. The economical method of construction, low operating costs and a high degree of living comfort make the property attractive for the investor, the operator and residents alike."

Dipl. Ing. Architect Yvonne Axler-von Berg

Partners and sponsors

  • Axler-von Berg Anders Architektur
  • CONESTA Consulting GmbH Co. KG
  • Malteser Duisburg
  • Ministerium für Klimaschutz, Umwelt, Landwirtschaft, Natur- und Verbraucherschutz (MKULNV)
Counselling centers:
  • EnergieAgentur.NRW

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