Study the impacts of external shading devices at top floors of high-rise buildings facing unobstructed skies

In many modern cities, most of the building developments are high-rise and are constructed in densely built regions. The amount of daylight received by the interior spaces at the lower floors may be significantly stinted. On contrary, rooms at the top floors facing unobstructed skies can cause excessive penetration of solar radiation and daylight into interior spaces leading to thermal and visual glare and increasing the cooling load. Shading devices are required to lower the cooling demand, eliminate discomfort due to glare and improve daylight distribution. External shading devices can be very useful for designing building facades with lower energy use and better daylight quality. This study analyses the external shading devices including overhangs, side-fins, and recessed windows on the daylighting performance for rooms located at the top floors facing different orientations. The simulations were carried out using RADIANCE program. The findings would be helpful to practitioners for conducting building façade and daylighting designs and aid in the evaluation of factors relating to visual comfort and building energy efficiency.