Retrofitting towards energy-efficient homes in European cold climates: a review.

Existing buildings represent a significant energy saving potential in Europe, and retrofitting the building stock is essential to reach European targets. Retrofitting measures should reduce the energy consumption as well as improve the indoor climate while still being cost-effective. This can be challenging in European cold climates. This paper discusses energy performance requirements and challenges in the retrofitting process. It also presents an overview of the retrofitting status and relevant energy saving retrofitting measures with their potential for residential buildings. Measures to lower the building's energy demand and electrical energy consumption and measures to control and monitor the energy use are discussed. Some research directions for the future of building energy usage are suggested. The literature indicates that significant energy savings can be achieved from retrofitting the building envelope. Relatively few research papers have been devoted to the energy saving potential of building control systems for existing residential buildings. However, these savings seem low compared to those that can be achieved through energy conservation. The actual savings from retrofitting the envelope, HVAC-systems and control systems are case specific and should be assessed for reference buildings of each housing typology. [ABSTRACT FROM AUTHOR]