Factors influencing the outcome of renovation projects

Abstract: In Sweden, housing accounts for about 23% of all energy consumption. Sweden wants to reach net zero carbon emissions by 2045; as such, it is likely that energy-saving measures for housing will be needed. Many existing buildings have been in operation for 50 years or more and are therefore in need of modernisation. At the same time, the population is increasing and so is the rate of urbanisation, which is why there is, and will be for the foreseeable future, a need for more housing. Energy-efficient renovation and vertical extension of buildings are potential solutions to these three needs. In this dissertation, three case studies are presented. In the first, buildings which were renovated to incorporate both energy saving measures and vertical extensions were assessed from both a financial viability and an environmental performance perspective. In the second, four different cases of vertical extensions were investigated, two which had been realised and two of which were still in the planning stage, in order to study the development process for extending buildings vertically. The third case study deals with the financial viability of energy-efficient renovation concepts with a focus on prefabricated multi-active facades.Overall, the studies reveal financially viable renovation concepts which can contribute to environmental performance. However, the analyses are sensitive and even small changes can alter the results; in addition, the actual outcome may differ from the results of the analysis, since the renovated buildings are planned to last for decades. While describing the development processes and the success factors can ease project realisation, renovations are complex projects and their effects are not completely beneficial. This research contributes to both practitioners and researcher by highlighting and discussing several factors whichcan influencing the outcome of renovation projects. By learning from other projects and trying to understand the development process renovation concepts can be identified. However, it is argued that renovation is a wicked problem and therefore there is no generic solution that can be applied. Moreover, analyses regarding renovation concepts are uncertain; nevertheless, these analyses are still valuable for decision makers and represent the bestattempts to assess the impact of renovation.