Abstract
Multi-family apartment buildings have the highest energy demand in Europe, consuming 68% of the total final energy use in buildings in Europe (Economidou et al., 2011). Most of them were built between 1945 and 1980 and are now ready for retrofitting and have a huge energy-saving potential. The apartment buildings located all around Europe share many common features; architecture, structure and materials. This makes them suitable for retrofitting with prefabricated modules which allow for cost efficient mass production. In addition building service technologies can be integrated in the modules and the residents can stay in their homes during retrofitting. Quantitative research methodology in the form of a questionnaire has been used to provide data about the use of and expectations for retrofitting with prefabricated modules in 11 European countries among stakeholders in retrofitting. Due to the exploratory nature of the research the intention has not been to test a hypothesis but to provide indicators with which to understand societal trends associated with deep retrofitting.
The findings show that the most important requirements a prefabricated retrofit solution has to offer to be an attractive alternative are; energy performance, adaptability to the building, efficient construction, flexibility in design, and adaptability to the resident's needs. The three most referenced characteristics of good retrofitting design were energy efficiency, cost and aesthetics. The greatest pitfalls associated with prefabrication were limited architectural freedom with poor architecture as a result and high costs.