Daylighting strategies for an infinitely long atrium: An experimental evaluation

Summary In a typical atrium building the daylighting of spaces adjacent to the atrium varies considerably with floor level. Two different techniques to overcome this problem are examined: varying glazing area or varying glazing type with floor level. Model studies in the mirror box at BRE show that both techniques achieve the goal of improving the balance of lighting within the adjoining spaces. The paper presents daylight factor measurements on the atrium surfaces and on vertical and horizontal planes in the adjoining rooms. A formula for the luminance distribution on linear atrium facades is developed, and simple rules of thumb for estimation of daylight factors in rooms adjacent to the linear atrium are proposed.