Daylight Performance of Louvred Shading on Atrium Skylight in Exhibition Gallery

Daylighting is often underutilized in regions characterized by tropical climates. In Malaysia, architectural designs frequently incorporate enclosed walls and facades to minimize solar heat gain. However, this approach limits the penetration of natural daylight into deeper interior spaces. As a result, larger and deeper spaces, such as exhibition galleries, often rely on artificial lighting to achieve adequate illumination, thereby increasing the building’s overall energy demand. To mitigate the reliance on artificial lighting, this study aims to identify and evaluate the effectiveness of vertical and horizontal louvred shading systems applied to an exhibition gallery's atrium skylight within a tropical climate context. Both vertical and horizontal louvred shading configurations were analysed using the VELUX Daylight Visualizer simulation software. The Phase 1 simulation results indicate that the vertical louvred Type D (D = 600 mm, L = 300 mm) and horizontal louvred Type 3 (D = 150 mm, L = 450 mm) configurations demonstrated superior daylight performance when applied independently to the atrium skylight. In contrast, the Phase 2 simulation revealed that combining both louvred shading systems significantly enhances daylight performance. The integrated Type D2 configuration—comprising vertical louvred Type D (D = 600 mm, L = 300 mm) and horizontal louvred Type 2 (D = 150 mm, L = 300 mm)—achieved the most optimal daylight distribution for the atrium skylight in the exhibition gallery compared to other design configurations.