DAYLIGHTING IN ATRIUM BUILDING: A STUDY OF THE INFLUENCE OF ATRIUM FAÇADE DESIGN
Free (open access)
Volume 6 (2011), Issue 2
109 - 121
Atrium spaces have the potential to make vital contribution to the sustainable strategy and consequently eco-dynamics of a building. The environmental benefits in terms of daylight, natural ventilation, and heating that an atrium offers are widely recognised. Daylight availability in an atrium space is generally high; however, this may not necessarily be true for the adjoining spaces. Previous studies indicate that the daylight performance of the adjoining spaces can be improved through the design of atrium facades, whereby there is a progressive increase in the fenestration from the upper to the lower floors. Therefore, this paper seeks to systematically investigate the effects of different atrium façades design characterised by varied distribution of fenestrations on daylight (DFs) in an atrium and horizontal penetration of daylight in its adjoining spaces under overcast sky conditions for a four sided, top-lit, square atrium building of Well Index (WI) 1.25. Studies were undertaken using computer simulation software programs ECOTECT and RADIANCE with the objective of understanding the influence of facades and providing guidelines for facade design to create optimal daylighting conditions in the adjoining spaces. Three main curves were developed, each of which included five options of 20%, 30%, 40%, 50% and 60% openings on top floor with a progressive increase in openings and 100% opening on the ground floor. Results demonstrate that façade compositions have a very limited influence on daylight in the adjoining spaces offering very little benefi ts to the lower floors, where daylight is critical. But increase in opening on the top floor may increase DFs significantly on the top two floors. For this study, the option of 60% opening on top floor with progressive increase to 100% opening on ground floor provided the best results.
Adjoining spaces, atrium, daylighting strategies, facade design, fenestration distribution