The Impact of Clerestory Window Height on the Performance of Fixed Horizontal Lightshelf on Daylighting Classroom in Dhaka, Bangladesh

Md Fahad Islam

doi:10.18034/ajase.v10i1.19

Authors

Md Fahad Islam Architect

Keywords:

Light shelf

clerestory window

daylight simulation

classroom

Abstract

This paper investigates the impact of clerestory window height on fixed horizontal light shelf performance regarding daylighting quality in classrooms. As a case study, a south-facing classroom of a university located in Dhaka was selected, and five alternative models of 3300 mm high case spaces were created with light shelves at the height of 2100mm above the floor finish. Varying heights of clerestory windows were used in the models to analyze the influence of clerestory windows on light shelves' performances. The three-dimensional models of the classrooms were first generated in Ecotect to investigate the interior illuminance level and uniformity distribution with static daylight performance metrics. The models were also imported to Radiance, a raytracing software, to create rendered images for crosschecking and validating Ecotect findings. Then, to compare the findings with dynamic daylight metrics, the results were verified and refined with DAYSIM. The result showed that a 750 mm high clerestory window with a fixed horizontal light shelf at the height of 2100mm above floor finish performed better for a classroom face south compared to other studied alternative clerestory window heights.

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