Energy Refurbishment of Family Houses in Serbia in Line with the Principles of Circular Economy

To achieve material efficiency, the ongoing initiative to improve thermal properties of family houses in the Republic of Serbia should include harmonization with internationally established and nationally adjusted principles of circular economy. The overall aim of this study was to propose a methodology for optimal decision making between alternative materials and components for energy refurbishment of façades in existing family houses. Together with developed criteria, and their belonging indicators, the methodology was tested on selected case study houses located in the central zone of the city of Belgrade. Using the VIKOR method, five suggested scenarios and three sub-scenarios for façade thermal upgrades were assessed against five determined types of criteria: Economic Cost, Function, Circularity Features, Appearance, and Innovativeness. Obtained results—ranking lists of proposed scenarios—indicate that the optimal solution for energy refurbishment of façades in existing houses could include polyurethane insulation material in combination with the wooden window frames and low-E insulation glass. In future research, it will be necessary to introduce an additional assessment criterion related to the ecological quality of proposed scenarios, as the study revealed that a gap between circularity-related quality, and ecological sustainability, of building materials could be significant.