ABSTRACT
This chapter helps designers to understand the nature of daylight as a resource and to establish a basis for their daylighting design. By comparing the actual daylight resource available with the requirements set by the building programme, one can establish daylighting targets for the building project in question, and evaluate different strategies for satisfying these targets. Daylight considers two components diffuse light from blue sky and clouds, and direct light from the sun. However, in crowded urban sites, reflected light from light-coloured buildings may provide useful daylight. The daylight available at the site relating to climate and site properties and the functions that require illumination in the building provides the starting point for analysing where daylighting is a viable option and to what degree one can expect to replace artificial lighting with daylight. The regional or overall daylight climate at a location is determined primarily by latitude and cloudiness.
