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

Abstract

Many regulations and initiatives to promote the reduction of the energy consumption and carbon emissions have been implemented in the building sector. However, they are mostly targeted for new buildings. In order to reach the goals that are being established, it is necessary to act in new but especially in the existing buildings, which correspond to the majority of the European building stock. Building renovation improves the buildings? energy performance, reducing the carbon emissions related to the operation of the building but 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, IEA EBC project Annex 56, developed a methodological framework to evaluate the cost-effectiveness of building renovation solutions which include a life-cycle impact assessment. Thus, using a particular case study, different renovation solutions are compared with and without considering the embodied energy. The results have shown that the embodied energy do not have a major impact on the evaluation of the cost-effectiveness of the renovation solutions, but as the renovation energy target gets closer to zero non-renewable energy level, its relevance increases.