Improving Thermal and Energy Performance of Buildings Through Building Performance Simulation-Based Optimization A Case Study of a Residential Villa in Cairo, Egypt

The building construction sector accounts for approximately 40% of global energy consumption and significantly contributes to greenhouse gas emissions, underscoring the urgent need for sustainable design practices. In hot-arid climates such as Cairo, Egypt, the dependence on energy-intensive cooling systems exacerbates these challenges, particularly in villa residences where conventional construction methods often overlook thermal performance. This study examines the potential of using building performance simulation-based optimization (BPSO) to enhance thermal and energy performance in a residential villa building in Cairo, Egypt. A baseline building model, reflective of typical local construction practices, was developed using Design Builder software with Energy Plus as the simulation engine. This model underwent parametric optimization of building envelope systems, specifically focusing on external walls and glazing systems configurations, evaluated across 25 design scenarios. The primary objective was to minimize energy consumption and related CO₂ emissions while ensuring indoor thermal comfort. The results indicated that the optimal building configuration, consisting of 160 mm-thick precast cement sandwich panels walls and 25 mm-thick double-insulated Low-E glazing, achieved a significant reduction in HVAC energy consumption and CO₂ emissions of up to 18.76% compared to the baseline building model. This study addresses a notable gap in simulation-based research of residential villas within hot-arid regions and offers a replicable framework for architects, developers, and policymakers to implement data-driven design strategies. Ultimately, it highlights the effectiveness of building performance simulation-based optimization in advancing thermal and energy efficiency and sustainability in Egypt's rapidly growing residential sector.