Prototyping eco-insulated panels for facade retrofits in public schools in Chile

In a context of climate change mitigation, improving the performance of existing buildings is essential, as the adverse effects range from the planet's health to people's well-being. In educational buildings, Indoor Environmental Quality (IEQ)—including temperature, humidity, air quality, lighting, and acoustics plays a critical role in students' attendance, motivation, and academic performance. However, achieving adequate IEQ remains challenging in aging school infrastructure, particularly in vulnerable contexts where limited budgets constrain maintenance and retrofit actions. This study focuses on the design and testing of prefabricated modules as a retrofit solution to mitigate thermal bridges in a modular school typology in southern Chile. The proposed system incorporates locally sourced timber and organic-based insulation materials to achieve a low environmental footprint. A comparative analysis was conducted between a retrofitted classroom and a control classroom using in situ temperature measurements and infrared thermography. Results show that the retrofitted wall system exhibits a more stable thermal response and significantly different surface temperatures compared to the control condition. In contrast, improvements in steel thermal bridges were less pronounced and not statistically significant, although variability decreased. Overall, the findings demonstrate the technical feasibility and potential effectiveness of the proposed retrofit system, while highlighting the need for complementary strategies to address localized thermal bridges. This study provides replicable insights for improving the performance of similar school buildings in Chile and other regions with comparable modular typologies.