Thermal Comfort in Tropical School Buildings under Changing Climate Conditions

This study investigates the impact of climate change on the indoor thermal comfort of school classrooms in a tropical environment, taking the city of Antsiranana in northern Madagascar as a case study. The analysis focuses on a standardized school building design promoted by the Malagasy Ministry of National Education. Using Design Builder software and climate projections based on the IPCC scenario, RCP 4.5, simulations were conducted from the year 2000 to 2050. Hourly climatic data in epw format were generated through Meteonorm 8.6 and calibrated against field measurements to ensure simulation accurancy. The results reveal a continuous rise in indoor air temperatures, with an average increase of approximately 0.4°C per decade. The hottest months, particularly January and December, show the greatest increases, with indoor temperatures reaching or exceeding 32°C by 2050, well above the commonly accepted thermal comfort thresholds for educational buildings in tropical climates. The PMV index demonstrates a strong linear correlation with air temperature, indicating a progressive deterioration in thermal comfort, especially during the warm season. PMV values in 2050 are associated with moderate to extreme heat stress conditions.In addition, a strong correlation is observed between indoor air temperature and radiant temperature with R ² values consistently above 0.99, confirming the reliability of air temperature as a predictor of thermal comfort. Meanwhile, a gradual decline in relative humidity is noted, particularly after 2030, pointing to increasingly dry indoor conditions likely to affect air quality and occupant well-being. The study provides a clear picture of the thermal dynamics in school environments under future climate scenarios and confirms that climate change will significantly affect thermal comfort in tropical educational buildings.