ABSTRACT

Energy retrofitting is argued to be the most feasible and cost-effective method for improving existing buildings' energy efficiency. As a sustainable development, building energy retrofits require the consideration and integration of all three sustainability dimensions: environmental, economic and social. The objective of this study is to estimate and compare the sustainable impact of building energy retrofits to determine the maximum sustainable benefit when implementing different energy-related measures. The proposed analysis consists of integrating three approaches for evaluating these benefits. Economic benefits are measured by estimating the payback period of energy-related measures, environmental benefits are measured by estimating the CO₂ equivalent saving per year due to the implementation of energy-related measures, and social benefits are measured by defining a “social impact index” that establishes the impact of energy-related measures on buildings' users. A case study is used to demonstrate the framework for four potential scenarios. The results show that for the case study, energy-related “controlling” and “upgrading mechanical system” measures have the highest sustainable impact among the identified energy retrofitting measures.