Indoor Air and Thermal Quality in School Buildings. Demonstration of BIM-Integrated IoT Window Signaling System

Indoor Environmental Quality (IEQ) plays a crucial role in the health, well-being, and cognitive performance of students in school environments. This study presents the integration of Building Information Modeling (BIM) and Internet of Things (IoT) sensors for real-time IEQ monitoring and dynamic ventilation control. A BIM-integrated window signaling system was developed using visual programming to process real-time sensor data and provide feedback on optimal window operation times. The methodology consisted of five phases: (1) development of a BIM model of the case study and calculation of window opening time, (2) on-site deployment of an IoT sensor system, (3) integration of real-time environmental data into the BIM model, (4) generation of a continuously updated digital twin for IEQ assessment, and (5) comparison between calculated ventilation times and measured environmental parameters. The system was tested in two classrooms of a school in Rome, Italy, where temperature and CO₂ concentration were continuously monitored. The results indicate that the calculated ventilation schedules effectively maintained indoor temperatures within recommended thresholds. However, CO₂ levels frequently exceeded the guide value threshold in one classroom, revealing discrepancies between the expected and actual window opening behaviors of occupants. The study underscores the role of occupant compliance in ventilation effectiveness and demonstrates how BIM can function as a dynamic decision-support tool by integrating real-time environmental data, automated parameter updates, and graphical trend visualization.