Towards Energy Efficiency in Existing Buildings: A Dynamic Simulation Framework for Analysing and Reducing Climate Change Impacts

This research presents a multi-scale framework designed for assessing the energy performance and climate vulnerability of three existing residential buildings in a small Central Italian municipality. By integrating dynamic energy simulations with high-resolution climate projections, the study investigated how the selected building typologies responded to changing environmental conditions. Validation against Energy Performance Certificates (EPCs) confirmed the framework's robustness in accurately capturing energy consumption patterns and assessing retrofit potential. The results revealed a general reduction in heating demand accompanied by an increase in cooling requirements under future climate scenarios, with notable differences across building types. The reinforced concrete building showed greater sensitivity to rising temperatures, particularly in cooling demand, likely due to its lower thermal inertia. In contrast, masonry buildings achieved more substantial energy savings following retrofit interventions, reflecting their initially poorer thermal performance and outdated systems. Retrofit measures yielded significant energy reductions, especially in older masonry structures, with savings reaching up to 44%, underscoring the necessity of customised retrofit strategies. The validated methodology supports future wider applicability in regional energy planning and aligns with integrated initiatives aimed at balancing climate adaptation and cultural heritage preservation.