Life-cycle costs and impacts on energy-related building renovation assessments

Abstract

Many regulations and initiatives to promote the reduction of energy consumption and carbon emissions have been implemented in the building sector. However, they are mostly targeted at new buildings. In order to reach the goals that are being established, while it is necessary to implement measures in new buildings, this is doubly the case for existing buildings, which correspond to the majority of the European building stock. Building renovation improves buildings’ energy performance and reduces the carbon emissions related to the operation of the building, but this involves adding new materials and technical systems. The production process of these new materials uses energy (embodied energy) and releases carbon emissions. In this sense, to evaluate the relevance of the embodied energy in building renovation, the International Energy Agency Energy in Buildings and Communities (IEA EBC) project, Annex 56, developed a methodological framework to evaluate the cost-effectiveness of building renovation solutions that includes a life-cycle impact assessment (LCIA). Thus, using a particular case study, different renovation solutions are compared both with and without consideration of the embodied energy. The results show that the embodied energy does not have a major impact on the evaluation of the cost-effectiveness of the renovation solutions, but that as the renovation energy target gets closer to a zero non-renewable energy level, its relevance increases.

Keywords:

• Life cycle impact assessment, LCIA, LCA
• building renovation
• energy efficiency
• carbon emissions
• embodied energy