Inquiry on the thermal performances of an experimental double-ventilated roof canopy in a school building in Mali

Cold-roof finishes and ventilated roofs are widely recognized solutions for mitigating overheating, and their combination offers the potential for enhanced performance. A notable variation of this approach, seen in high-end architectural projects in hot climates, features high-albedo corrugated metal roof canopies positioned above solid flat roofs, creating a wide ventilated space beneath. This configuration merges the simplicity of flat roofs with an extreme form of the attic configuration to effectively dissipate solar heat gain. This study hypothesizes that increasing the number of ventilated thermal barriers beyond one can further improve heat dissipation. To test this hypothesis, the thermal performance of an experimental doubleventilated- cavity roof was evaluated in a school in Mali through monitoring and environmental simulations, complemented by parametric analyses. The results demonstrate that the double- ventilated-cavity roof outperforms conventional single-cavity designs, achieving lower indoor temperatures and greater resilience to the ageing of roof cover materials.