Daylighting of classrooms through courtyards

Due to in adequate architectural standards and bad building design, one can frequently find school buildings with very bad performance regarding energy efficiency. This paper is part of a extensive research program aiming to examine the influence several architectural parameters in the environmental and energy performance of classrooms in warm humid tropics. Here it presents a parametric investigation on the effect of four different courtyard configurations on daylighting of typical Brazilian classrooms. The methodology was based on simulations produced by a computer program called Lumenmicro. Models without openings to the courtyard were compared to another ones with a clerestory, open to the courtyard. Simulations have shown that the natural lighting coming from the courtyard may produce an increment of up to 55% in the average illuminance level and up to 120% regarding the lowest value, considering typical internal and external surface reflectances. It also produces a significant improvement on the uniformity ratio. Results have shown that there is scope to rely mostly on daylighting, to provide adequate lighting to classrooms maintaining the typical building configuration, even under cloudy conditions, if the internal surfaces are light colored.