Additional storeys and energetic modernisation

Köln-Niehl „Ford estate“

(North-Rhine Westphalia)


Image: Saniertes Wohngebäude

Source: LEG Management GmbH

The Ford estate is situated about 6 kilometres in the north of the inner city of Köln (approx. 1 million inhabitants) in the district of Niehl. The most important industrial area of Cologne, which is characterised by automobile manufacturers and related suppliers, starts in the east of the estate.

Having once been built in the early 1950s for factory employees, the estate showed a high need for modernisation at the beginning of this millennium. The flats just had an average living space of 47 square metres. Furthermore, with 246 kWh/m²/year, the head demand was very high. The altogether 310 housing units with a living area of 14,211 square metres spread over eleven rows of houses with north-south orientation. The extensive open space with old trees between the various rows of houses are typical for the estate.

Due to the favourable situation close to the city centre, the estate owner found it important not only to modernise but also to create additional living space by using existing space.


Project description

Image: Blick von der Gartenseite auf saniertes Wohngebäude

Source: LEG Management GmbH

The goal of renewing the estate was energy-efficient refurbishment according to the requirements of the “50 Solar Energy Housing Estates in North Rhine-Westfalia” project, to add storeys and at the same time to maintain the urban development-oriented character and open space qualities.

The residents of the old estate stock were informed about the planned modernisation in 2006. Comprehensive conversations with the house communities and the board of tenants helped to gain large acceptance for the planned building project. Despite the announced rent increase, the residents could be convinced of the modernisation measures by lower additional costs, changed ground plans and balcony extensions.

By creating additional living space by adding a storey, the open space with playgrounds and gardens could be maintained. At the southward gabled ends of the houses, the architects planned additional maisonettes with pent roofs oriented towards the south. All in all, creating additional living space by using existing space resulted in 81 new housing units and the total living space being extended by approx. 6,500 square metres, which means 45 per cent more living space.

Futhermore, all flats in the three-storey buildings were modernised. They were provided with new bathrooms, kitchens and large balconies. Their ground plans were revised according to present rquirements so that 264 modernised housing units were left over. Together with the 81 new units from the storey additions, the Ford estate today comprises a total of 345 housing units based on different ground plan variants. One- to four-room flats with 39 to 130 square metres offer space for singles, couples, elderly people and families. The residents can be heterogeneously mixed in this way. Three quarters of the tenants stayed in the estate following modernisation.

Apart from creating additional housing space, the buildings were energy-efficiently refurbished. The concept is based on a combination of energy saving and using renewable energy sources in the field of housing. Two building standards were realised in the Ford estate. In the existing buildings, the building standard was 30 per cent below the legal German Energy Saving Ordinance standard for new buildings – which corresponds to the “KfW-60-Standard” (Energy Saving Ordinance standard funded by the German KfW credit bank).

The storeys added were built according to “KfW-40-Standard” or “3-Liter-Haus-Standard“ (energy demand expressed by tonne of oil equivalent). The heating energy demand of the eleven rows of houses could be reduced by an external thermal insulation composite system, by insulating the cellar and roof areas and installing new windows and doors with heat protection glasses. It means at the same time that the climate-damaging carbon dioxide was reduced from approx. 3,000 tonnes to around 180 tonnes per year.


Project chronology

Image: Blick von der Gartenseite auf saniertes Wohngebäude

Source: LEG Management GmbH

Year Event
2003 idea of concept
2006 planning procedure started
2006 residents informed
2007 construction activities started
2010 construction activities completed


  • To modernise buildings energy-efficiently
  • To create additional modern housing
  • To maintain the urban development structure and open space quality

Types of measures

Image: Neue Balkone

Source: LEG Management GmbH

  • Adding storeys
  • Altering ground plans
  • External thermal insulation composite systems
  • Insulating the cellar and attic storey ceilings
  • Installing new windows and doors with heat protection glasses
  • Making the whole building air tight
  • Equipping flats with controlled ventilation systems
  • Installing a ventilation system with heat recovery
  • Using thermal solar energy


Image: Straßenansicht auf saniertes Wohngebäude

LEG Management GmbH

In Köln-Niehl, creating additional living space by using existing space was favourably combined with energy-efficient modernisation measures. That means the primary energy demand could be reduced to 47 kWh/m²/year, CO2 emissions to 9.5 kg/m²/year. By choosing the addition of storeys as a densification measure, the large open space between the rows of houses and the old trees could be maintained. Following completion of the project, more and at the same time modern housing will be available without the open and green space or the urban development character of the estate being negatively changed.




Further information

The projekt site ist to be found at postal code: 50735 - town: Köln - street: Königsberger Straße 8.



  • Client/Investor: LEG Wohnen NRW GmbH. Kundencenter Köln. Großer Griechenmarkt 2, 50676 Köln, Germany, phone: +49(0)2 21 / 2 09 05-0, fax.: +49 (0)2 21 / 2 09 05-12, email: kc-koeln@leg-nrw.de, website: http://www.leg-nrw.de/
  • Architect’s office: Archplan. Münster, Gildenstraße 2g 48157 Münster, Germany, phone: +49 (0)251 14180-0 fax +49 (0)251 14180-18, website: http://www.archplan.de/
  • Energy planning: KaTplan GmbH: Scharnhorststraße 48, 48151 Münster, Germany, phone: +49 (0)251 48 43 70, fax +49 (0)251 48 43 711, email: info@katplan.de, website: http://www.katplan.de/

Record inserted on 10.12.2014 by the Federal Institute for Research on Building, Urban Affairs and Spatial Development (BBSR) within the Federal Office for Building and Regional Planning (BBR).

Last update: 21.09.2015