Measurement results and experiences from an energy renovation of a typical Danish single-family house

In 2006, new tighter energy performance requirements were introduced in Denmark for both new buildings and renovation. These demands are based on the directive on Energy Performance of Buildings, the EPBD (2002/91/EC). In general the effect of the new requirements for renovation is that existing buildings should be brought up to the energy performance level of new buildings in connection with larger renovations and other substantial changes in the buildings. To demonstrate how it could be done in small residential buildings, a thorough energy efficient renovation of a typical Danish single-family house from the 1960/70’s with need of renovation was initiated by Rockwool International in 2005 and the results from the project are presented in the paper. The house is typical as about 500,000 of a total of 1.1 million Danish detached single-family houses were erected in the 1960/70’s. The purpose of the project has been to demonstrate and document that energy efficient renovation of a typical single-family house would lead to large reductions in energy consumption in a cost efficient manner and at the same time improve living conditions and achieve a commonly acceptable design. A detailed monitoring program was implemented in order to document the energy performance and indoor climate before and after the renovation, which included measurements of energy consumptions, air change rates using blower door and tracer gas methods, indoor climate conditions and solar radiation. One whole year of measurements before and after the renovation is included in the paper. The lessons learned during the process of renovating the house are described. Also, the cost effectiveness of the energy saving measures is accessed, taking into account the twofold benefit of renovation, i.e. the energy savings and the rehabilitation of the building elements physical condition (longer lifetime). Preliminary results from the project are described in [Tommerup 2007]. A similar energy renovation project was carried out a few years ago regarding an old poorly insulated single-family house built in 1927. This project showed that large profitable energy savings are indeed possible. The results are summarized in [Overgaard 2005]. References: [Tommerup 2007]. Tommerup, H. Svendsen, S. Energy Renovation of a Typical Danish Single-family House. In conference proceedings of the 11th International Conference on Passive Houses 2007, Bregenz, Austria. p. 197-202. [Overgaard 2005]. Overgaard, L.L. et al. Energy renovation of an old single-family House, Nordic Building Physics Symposium, Reykjavik, 2005, proceeding vol. 1, p. 260-266.