Study of Optimal Area of Atrium for Daylight Utilization (Case Study: Administrative Building in Qazvin, Iran)

Atrium has been used with various shapes and purposes in many different climates and buildings especially public ones. It is mainly used to take advantage of daylight in buildings. Therefore, achieving the optimal atrium dimensions is of great importance. This research employed computer simulation using Ecotect and Radiance for daylighting. The collected database is created using simulations for different atrium proportions in IRAN-Qazvin climate zone, where using atria could improve building performance based on the clear sky condition. The aim of present study is assessing the impact of atrium width and clerestory height on the amount of Average Daylight Factor (ADF) in different floors of horizontal top-lit atria and determining the appropriate geometrical sizes for the ten 5-storey, four-sided atriums to provide sufficient daylight in office spaces. Qazvin climatic conditions were simulated in Ecotect, Design Builder and Radiance. Ten 5-story administrative buildings with atrium ranging from 5%-50% area and one without atrium were modeled. The results showed that optimal samples were buildings with 10% and 15% atrium area in terms of daylight utilization.