PERTANIKA JOURNAL OF SCIENCE AND TECHNOLOGY

Daylight is an important component of indoor environmental quality, yet its distribution in tropical high-rise low-cost housing is often uneven due to variations in building height, façade orientation, and unit depth. This study aims to validate the Integrated Environmental Solutions – Virtual Environment (IES-VE) simulation software for assessing daylight performance in tropical high-rise low-cost housing in Kuala Lumpur. A quantitative approach was adopted, combining field measurements and simulation modelling. Field measurements were conducted at different floor levels and room depths to investigate horizontal and vertical daylight distribution within residential units. The Daylight Ratio (DR) was used to represent actual daylight conditions under tropical sky environments, while simulation results were evaluated using the Daylight Factor (DF). The comparison between field measurements and simulation results showed differences ranging from 15% to 20%, which fall within the commonly accepted validation threshold. Statistical validation using Mean Bias Error (MBE) and Root Mean Square Error (RMSE) indicated small deviations between measured and simulated values, while correlation analysis demonstrated a strong agreement with a coefficient of determination (R²) of 0.9917. The findings confirm that IES-VE can reliably simulate daylight performance in tropical high-rise residential buildings. The validated simulation model provides a reliable platform for future climate-based daylight modelling and visual comfort assessments, including the evaluation of daylight availability, solar exposure, and glare performance. The outcomes of this study contribute towards the development of evidence-based daylight design recommendations and support future improvements to daylighting guidelines for tropical high-rise residential buildings.