Energy Performance and Thermal Comfort in Madrid School Buildings Under Climate Change Scenarios

Resumen

Featured Application The findings of this study can guide the design and prioritization of energy retrofitting strategies in existing school buildings. Public administrations, technical offices, and design teams can use simulated scenarios to evaluate the impact of passive and active measures-such as envelope insulation, solar control, and mechanical ventilation-under both current and future climate conditions. This approach is especially relevant for high-occupancy buildings in warm or temperate climates, where indoor comfort and energy efficiency must be carefully balanced.Abstract This study presents a detailed analysis of the energy performance and thermal comfort conditions in four existing school buildings located in Madrid, Spain. Dynamic simulations were conducted using TeKton3D-(iMventa Ingenieros, M & aacute;laga, Spain)- an open-source tool based on the EnergyPlus engine-to model four improvement scenarios: (I) current state, (II) envelope retrofitting with ETICS and high-performance glazing, (III) solar control strategies, and (IV) incorporation of mechanical ventilation with heat recovery. Each building was simulated under both current and projected 2050 climate conditions. The case studies were selected to represent different construction periods and urban contexts, including varying levels of exposure to the urban heat island effect. This approach allows the results to reflect the diversity of the existing school building stock and its different vulnerabilities to climate change. The results show that envelope retrofitting substantially reduces heating demand but may increase cooling needs, particularly under warmer future conditions. Solar control strategies effectively mitigate overheating, while mechanical ventilation with heat recovery contributes to improved comfort and overall efficiency. This study highlights the trade-offs between energy savings and indoor environmental quality, underlining the importance of integrated renovation measures. The study provides relevant data for decision-making in climate-resilient building renovation, aligned with EU goals for nearly zero and zero-emission buildings.