ABSTRACT
Designing buildings that use daylight as the primary illuminant requires a different mindset than is often taught in architecture schools, because daylight is dynamic, big, and follows its own whims. To do a good job, it is essential to master solar geometry. The experience of twilight and nightfall also vary dramatically by latitude. Other important regional differences in daylight quality are influenced by weather patterns, landforms, and cultural inheritance.
Daylighting buildings via toplighting is very efficient and has been used since ancient times. Recent innovations in skylight technology have greatly improved their performance. Sidelighting may be the most common approach to daylighting, but has more challenges to ensure visual quality. For example, contrast glare can be avoided if daylight enters a room from at least two directions. The best way to balance the visual conditions in a daylit room is usually with more daylight, because daylight is always in sync with itself.
New efforts are underway to evaluate the success of daylight design. Electric lighting should ideally be considered as a supplement to daylight. Daylight and electric light are very different, and can be complementary. Window management via curtains, blinds, or shades is critical, as are the user-interface systems for controlling them. Finally, placement of windows not only lets daylight in, but also frames a view out, which can drastically alter an occupant’s perception of the space.
