This study evaluates the energy performance of a multi-story social housing complex in Budapest’s 8th District, focusing on the challenges of refurbishing aging urban buildings. Using dynamic simulation software (IDA ICE), the research analyzes heating and cooling loads, energy consumption patterns, and the potential impact of targeted refurbishment measures. Results show that heating accounts for over 85% of total energy consumption, primarily due to heat losses through poorly insulated building envelopes and thermal bridges. Simulation results indicate that energy-efficient interventions, such as enhanced insulation and upgraded window systems, could reduce heating demands by 50–80%, ensuring compliance with EU energy performance standards. By providing detailed insights into effective refurbishment strategies, this study contributes to sustainable urban renewal and offers a practical framework for policymakers, urban planners, and architects aiming to improve the energy efficiency of existing residential buildings.