Assessment of daylight quality in simple rooms
The present report documents the results of a study on daylight conditions in simple rooms of residential buildings. The overall objective of the study was to develop a basis for a method for the assessment of daylight quality in a room with simple geometry and window configurations. As a tool for the analyses the Radiance Lighting Simulation System was used. A large number of simulations were performed for 3 rooms (window configurations) under overcast, intermediate, and 40-50 sunny sky conditions for each window (7 months, three orientations and for every other hour with direct sun penetration through the windows). A number of light indicators allowed understanding and describing the geometry of daylight in the space in a very detailed and thorough manner. The inclusion of the daylight factor, horizontal illuminance, luminance distribution, cylindrical illuminance, the Daylight Glare Index, vertical-to-horizontal illuminance ratio as well as scale of shadow gave valuable information allowing a detailed description of the three-dimensional geometry of daylight in the space. It should be mentioned however, that there is no universal definition of light quality. The approach in this study was to analyse differences in daylighting conditions for a number of lighting parameters. The results gave clear indications of, for instance, which room would be the brightest, under which conditions might glare be a problem and which type of window would yield the greatest luminous variation (or visual interest), etc.