Our website uses cookies to help provide you with the best experience tailored to your interests. To use the website with full comfort, please accept to receive all cookies on our website. For more information with regard to Cookies please see our Privacy policy.

Accept Decline

Single-family house in Sundern

The residential building built in 1905 and owned by Melanie and Frank Brakel is located in the city of Sundern in the Sauerland region.

As part of the renovation in cooperation with architect Wolfgang Schröder the 260 square metre villa was modernised with respect to energy technology and is now virtually self-sufficient. In addition to being structurally sound, the intelligent use of HVAC technology, such as an air/water heat pump, thermal solar collectors and photovoltaic modules contribute to the energy efficiency of the building.

With its charming turn-of-the-century architecture, the 260 square metre villa is the new residence of the family of four. The original building is structurally sound with 50 to 120 centimetre brickwork, which eliminated the need for additional insulation. Only the installation of new doors and windows and retrofitting of insulation in the upper ceiling were necessary to minimise the heat transmission losses. With a value of 1.3 h-1, or an air exchange rate of 1.3 times per hour, the villa is very well insulated and nearly fulfils the standards of a new building.

The energy-related renovation was implemented with the consistent use of renewable energy sources. The old oil-fired heating was replaced by a geoTHERM air/water heat pump with an output of about 16 kW, which completely covers the house’s heat base load. The location of the villa is favourable in terms of energy yield via regenerative sources. Almost optimally aligned on the roof of the adjoining former factory hall, “auroTHERM exclusive” solar collectors generate the energy for heating the domestic water. The solar energy thus obtained and the unneeded heating energy from the heat pump is stored virtually loss-free in an 800 litre allSTOR multi-function tank. In addition, 102 photovoltaic modules on the roof generate the entire electric power requirement. With primary energy savings of up to 20 percent the old radiators were exchanged for surface heating elements in the walls and floors. Controlled house ventilation further improves the indoor climate. The recoVAIR ventilation system ensures the necessary exchange of air with up to 95% recovery of the exhaust air.

Facts and figures

Construction sign
Designation, name of project:Single-family house in Sundern
Typology:Single-family house
Location:Sundern, Hachen District
  • Year of construction: 1905
  • Renovation: December 2006 – April 2007
Key figures –
260 m² living space
Key figures –
Energy concept:
  • Installation of a geoTHERM VWL S air/water heat pump with 16 kW with an air/brine heat exchanger in combination with a thermal solar system
  • 800 litre multi-function tank
  • Wall and floor heating surfaces from Pedotherm
  • recoVAIR controlled house ventilation
  • Insulation of the upper ceiling, replacement of windows and doors
Vaillant products:
  • geoTHERM VWL S air/water heat pump with air/brine heat exchanger
  • allSTOR 800 litre hot water tank
  • 6 auroTHERM exclusive thermal solar collectors
  • 102 auroPOWER photovoltaic modules
Building owner:Frank and Melanie Brakel
Architects:Planwerk Architekten und Ingenieure
Dipl.-Ing. Wolfgang Schröder, Sundern
Facilities planner:Pedotherm GmbH
Contracting companies:Pedotherm GmbH,