Cost-benefit analysis of sustainable upgrades in existing buildings: A critical review

Sustainable upgrades in existing buildings embrace activities enhancing the economic, environmental, and social aspects of the building and its occupants. This research aims to review the current body of knowledge related to cost-benefit analysis (CBA) of sustainable upgrades in existing buildings, while also investigating the CBA methods, cost modeling approaches, and diverse benefits explored in the literature. Moreover, the latest findings, trends, and research gaps for future investigations are identified. Despite the challenges and limitations of CBA, this methodology remains a powerful tool, providing valuable insights for the decision-making process of building upgrades. Most studies prioritized energy savings as a primary benefit in the CBA of building upgrading measures, with greenhouse gas emissions reductions taking the next significant role. This review of recent studies underscores the critical role of sensitivity and uncertainty analysis in the CBA process, highlighting energy price and discount rate as key uncertain variables. This study contributes to the field of sustainability assessment of upgrading measures by providing a deeper understanding of CBA and highlighting research gaps and future directions in this field.