Optimum Geometry of Double-skin Self-Shading Facade of Classrooms with the Aim of Creating Energy Saving and Visual Comfort in Isfahan Province, Iran

The significant energy consumption in educational spaces worldwide and its environmental impact greatly influence the quality of space, learning levels, and student comfort. Despite offering free school energy costs, developing countries like Iran have not established specific design principles to ensure student comfort. Additionally, the poor design of school building exteriors, such as the common installation of large, unshaded windows in Iranian schools, causes glare issues. The primary objective of this study is to control direct sunlight and increase shading, thereby reducing its impact on energy consumption and enhancing visual comfort. This paper proposes a novel solution that combines a self-shading facade with a double-skin facade for classroom spaces. The study variables, involving the modification of the geometry of the double-skin self-shading facade via DesignBuilder software and the Daysim plugin, were compared to a simple double-layer facade. Based on the results, the optimal scenario for the self-shading double-skin façade with the specifications of a triangular pyramid module shape, ridge position fold 3/2 the module height, cavity depth 7.0, and number of module 2×2 exhibited 40% lower cooling load, 25% lower heating load, and 95% lower lighting load than a simple double-skin facade. At the same time, all scenarios of the new solution provided better visual comfort and daylighting criteria compared to the simple double-skin facade. The modularity and use of indigenous brick materials in the double-skin self-shading facade design reduce construction costs.