Optimizing Glazing Ratios: Enhancing Natural Lighting and Visual Comfort to Reduce Energy Consumption in Classrooms

The quality and quantity of daylight and indoor thermal conditions have been confirmed by various studies to significantly influence the learning and teaching performance and health of both students and teachers within classrooms. As the problem of energy consumption in Egypt increases, the primary goal of using natural light in schools is to reduce energy consumption and costs, but it must also improve student performance. Achieving maximum natural illumination through appropriate glazing ratios is crucial for improving comfort and productivity. Enhancing the amount of natural light in classrooms has benefits, but it is important to cope with potential disadvantages to establish healthier and more sustainable learning environments. The excessive use of windows and insufficient shading and insulation may increase the absorption of solar heat and glare, while also reducing the visual comfort in classrooms. The study focuses on reducing energy consumption and the need for artificial lighting, increasing productivity and visual comfort, in addition to clarifying the effect of window-to-wall ratio and their effect on the ratios of natural lighting within the classrooms, to create healthier and more sustainable study environments. The Design Builder software was used to simulate the impact of different window opening sizes' impact on natural classroom lighting. Seven classroom models were designed, identical in all aspects except for the window opening size, which varied between 30% and 90% of the external wall area. The classroom dimensions were 9m by 6.7m, with the external wall (containing the windows) measuring 9m by 2.7m. The natural lighting performance was evaluated based on several metrics, including average illuminance (Lux), minimum maximum illuminance, daylight factor, glare index, and thermal comfort and energy inside the class.