A Numerical Assessment of Daylight Performance of Office Buildings in Dhaka, Bangladesh: Introducing Light Shelves to Enhance Daylighting Quality

  • Nafis Sadat Department of Architecture, Faculty of Civil Engineering, Rajshahi University of Engineering and Technology, Rajshahi, Bangladesh¬
  • Nabilah Nargis Department of Architecture, Faculty of Civil Engineering, Rajshahi University of Engineering and Technology, Rajshahi, Bangladesh¬
Keywords: Daylighting, Useful Daylighting Illuminance, Light Shelves, Office Buildings, Tropical Climate


Daylighting is one of the significant factors affecting the working environment in an office which is recognized as a vital source of energy savings. Occupants require proper daylight for desk jobs in their working spaces which largely depends on a set of internal and external aspects. This paper aims at analyzing the natural daylighting performance of the office buildings in Dhaka and providing a few design options concerning light shelves in order to enhance interior daylighting performance. A total of eleven commercial office buildings were selected in the survey based on a set of building parameters that has significant effects on daylighting. Among those selected buildings, one typical office building was further analyzed and simulated for a more detailed assessment of daylighting performance. Daylighting performance is assessed in terms of illuminance value concerning useful daylighting illuminance. The resultant data shows the inner office region lags in terms of illuminance value and is not very suitable for office works. Hence, light shelves were introduced as architectural design elements which were then simulated at different heights and angles to find out the optimum solution for daylighting enhancement which will save electrical lighting energy consumption.


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