Options of modelling refurbishment in LCA: continuous improvement strategy and next life cycle approach

Compared to other goods, buildings have a long lifespan. It is therefore the norm and not the exception that adaptation will be needed at some point in their life cycle to changing environmental conditions, technical progress and new/additional user requirements. The adaptation of existing buildings to future challenges in the form of refurbishment contributes to sustainable development. The proportion of refurbishments is increasing in both absolute and relative terms in the building sector in Europe. It is therefore surprising that the modelling particularities of refurbishment in the context of a life cycle-based environmental performance assessment are still neglected in the EN-standards. The paper deals with these particularities. Specifically, it presents a typology of approaches starting with a distinction between planned refurbishment as B5 and unforeseen refurbishment as an independent design and construction task / next life cycle, as well as the status of the discussion in selected countries. Recommendations for action for the life cycle assessment are given for specific decision-making situations.