Daylight Availability

From eLADwiki
Jump to: navigation, search


Sky Component, External Reflected Component, Internal Reflected Component
Annual Daylight Illuminance Ranges at Los Angeles, CA; Climate Consultant (UCLA)
Horizontal Incedent Solar Radiation at San Francisco, CA; (Images: Autodesk Ecotect Weather Tool/UW IDL)

Daylight availability comprises available light at a site based on time of day, time of year, sun position, and sky condition. Climate specific issues such as cloud cover play a critical role in determining daylight availability at a particular region. Several reference sources exist for determining daylight illuminance availability in major cities around the globe.

Daylight availability at a given point and time within a building interior is a combination of three primary components. These include the sky component, the exterior reflected component, and the interior reflected component.

The sky component includes diffuse daylight and direct sunlight produced at a given point in time from the sky dome, excluding any site obstruction such as adjacent buildings, tree canopy or other building elements that reduce access to sky light.

The exterior reflected component includes light reflected from adjacent exterior surfaces in the landscape including existing buildings, site surfaces, and surrounding vegetation.

The interior reflected component refers to light inter-reflected within an interior space and is a function of the room geometry and ceiling, floor, and wall reflectances, as well as the reflectance values of interior items such as furnishings.

Section Key Resources
  • Brown, G. Z., Dekay, Mark (2000). Sun, Wind & Light: Architectural Design Strategies. Wiley; 2nd Ed.
  • Robbins, Claude L. (1986). Daylighting Design and Analysis. Van Nostrand Reinhold Company, Inc.
  • Carmody, J., Selkowitz, S.E., Lee, E.S., Arasteh, D., Willmert, T. (2004). Window Systems for High-Performance Buildings. New York: Norton & Company.
  • Hopkinnson, R. G., Petherbridge, P., Longmore, J. (1966), Daylighting. William Heinemann, LTD.
  • Lam, W.M.C., (1986) Sunlighting as Formgiver for Architecture, Van Nostrand Reinhold
  • Fontoynot, M., Ed., (1999). Daylight Performance of Buildings. James and James

Lead Author(s): Chris Meek

Page Key Resources
  • No publications general to this page have been listed.
  • No links general to this page have been listed.
70px-Cc att share.png Except where otherwise noted, content on this site is licensed under a         
           Creative Commons Attribution-ShareAlike 3.0 License
Personal tools