Reducing greenhouse gas (GHG) emissions through energy reduction in buildings is a high priority for policy-makers in the European Union and elsewhere. However, although long-term sustainability targets exist on the societal level, it is not obvious how these targets may trickle down to individual sectors and further down to specific organizations or buildings. The aim of this paper is to illustrate an approach for evaluating renovation measures in order to identify appropriate target levels in early project stages and what is needed to achieve a number of proposed sustainability targets. The evaluation approach is supported by a tool that can be seen as an aid to making rough estimations of the environmental impacts. Sustainability target levels in a Swedish context are presented for three issues: operational energy use, GHG emissions due to total energy use for building operation, and embodied GHG emissions due to production of materials. The approach to support well-grounded retrofit decisions is shown with a case study. The tool developed, in combination with a suggested step-by-step evaluation approach, provides an effective way to evaluate various potential improvements, and their consequences, in early project stages. However, other tools with similar functionality may be used. Results from the case illustration imply that it is possible to achieve the proposed sustainability targets for operational energy use by implementing nine measures. However, the targets for GHG emissions for operational energy use and embodied GHG emissions were not achieved because of an energy supply with too high a share of nonrenewable fuels.
Buildings from the record year era are now 40 – 55 years old and in many cases in need of extensive renovation measures. This need for renovation could be seen as an opportunity to achieve overarching sustainability target levels and to perform renovation with a holistic approach. This thesis aims at creating support for the formulation and achievement of adequate environmental targets that relate to overarching Swedish Environmental Quality Objectives. The overall aim of the thesis is to contribute to an understanding of the current situation of environmental management in renovation processes. The scope of this thesis is limited to the aspects energy use and greenhouse gas (GHG) emissions from energy use and material production. This thesis contributes to this aim with a stepwise procedure for evaluation of measures together with a proposal for target levels for three environmental aspects. The first paper appended to this thesis investigates how six Swedish property owners performed renovation projects. From this paper it can be concluded that the main barrier (except economic ones) are characterized by lack of knowledge about overarching objectives and what aspects define a sustainable built environment. The second paper assesses embodied GHG emissions due to material production for the totality of measures needed to reduce operational energy demand per unit heated floor area by 50% compared with 1995. On a national level, embodied GHG emissions are estimated to be 12% of the reduction of GHG emissions achieved by operational energy demand reduction. The final paper appended to this thesis uses a case study building to illustrate a working procedure to identify project-specific target levels for three environmental aspects. In addition, it identifies indicative improvements necessary for the achievement of long-term targets for those aspects, which could be focused and further investigated in later project stages with the help of a long-term plan of action.