Potentials for a complex and integrated refurbishment of post-war housing stock of Serbia

This paper presents the possibilities for energy retrofitting of existing multi-family residential buildings constructed during the mass construction period in Serbia, which exhibit high energy consumption for heating. The research focuses on determining approaches to achieve deep energy renovation goals through interventions on the building envelope. The study analyzes the application of a methodology of complex and integrated refurbishment by adding volumes (increasing usable space) to existing multi-family buildings to achieve high energy efficiency, modernize residential units, and improve vertical building communications. The study includes analysis of two selected residential multi-family buildings of different types constructed during the same period. The research examines the energy performance of the existing state of selected buildings and two variants of improving the building envelope’s energy performance: refurbishment scenario 1 (without volumetric additions) and refurbishment scenario 2 (with volumetric additions). Current energy regulations in Serbia only analyze energy consumption for heating, limiting the calculation of total energy consumption. Therefore, this study calculates heating energy consumption and determines the energy class based on the results. Based on the Knaufterm simulations, the energy savings for heating energy consumption compared to the existing state are in case study 1 (RS1 73.5%, RS2 79.5%) and in case study 2 (RS1 68.3%, RS2 77.3%). Furthermore, the research explores the application of prefabricated lightweight timber assemblies in energy refurbishment that meet not only energy but also broader environmental requirements derived from the concept of sustainable architecture.