The Analysis of Natural Lighting-based Visual Comfort for Classrooms Building by Using Velux Daylight Visualizer

This study aims to determine the level of natural lighting at a school building carried out with the use of the Velux Daylight Visualizer (VDV) software. VDV is a software for analysing natural lighting on building model. The output is Daylight Factor (DF) or Daylight Natural Lighting Factor and Illumination (E). E value is the main indicator of the level lighting and visual comfort in the room by referring to simulation results referring Indonesian’s Standard of SNI 03-2396-2001 for visual comfort. Results shown the existing conditions in the classroom have a low level of lighting with majority measurement points having average lighting level below 250 lux. To improve the natural lighting quality in the classrooms, variations of walls-to-windows ratio (WWR) applied the model. The variation of WWR is conduct an experiment to substitute its value in regression equation. With the increasing size of the opening at WWR 30%, the distribution of DF values at measurement distance 1 meter and 2 meters increases compared to WWR 20%. Trend also continues to occur at WWR 40% to WWR 60%, the DF value has increased quite significantly, especially at several points blocked by walls or meeting points between light from 2 adjacent windows.