Daylighting, Architecture and Health: Building Design Strategies

Daylighting legislation
2
2.1 Solar zoning legislation
2.2 Legislation based on window size
2.3 Quantity of illumination legislation
Proponents of daylighting have focused primarily on its
potential for energy savings in efforts to popularize its use.
Because of technical innovations over the years, electric lighting
equipment has become more energy efficient and lighting
energy standards have reflected this. Despite this progress,
however, lighting remains a major energy consumer in large
buildings. According to the U.S. Electric Power Research
Institute, in the United States ’ commercial sector an average
of 37% of the electricity used is consumed by electric lighting
(Energy Information Administration, 1998). Daylighting has
the potential not only to reduce the amount of electric energy
used for lighting but also to lower peak demand and reduce
cooling loads caused by heat released into the space by the
lighting fixtures. Despite these substantial benefits, daylighting
is not a mainstream architectural feature in the majority
of buildings. Some of its proponents suggest that the argument
for daylighting should no longer be based on energy
savings because that approach has not proved effective;
rather, the argument should focus on the benefits of daylighting
for health and well-being (Boubekri, 2004b).
Daylighting is not a commonplace design application
because no compelling legislation mandates it. Daylighting
legislation is beset by many problems, some germane to the
general field of lighting and others more specific to the nature
of daylight as a source of illumination. The spectral quality of
daylight, which is difficult to duplicate artificially, makes it an
almost entirely different type of light to that produced by any