There are several parameters that have an influence on daylight access, or rather, daylighting performance of a room:

  • Climate: the climate in which a building is located, defines how many days you have daylight availability and how many days you have an overcast sky with limited access to daylight.
  • Latitude: the latitude of the site in which a building is located, defines the position of the sun (i.e. solar altitude) in different seasons. The farther you get from the equator, the more solar altitude changes between summer and winter.
  • Room geometry: distance from external windows in a room (i.e. depth of the room) has a huge impact on daylight access and daylighting performance of the room.
  • Obstructions: external obstructions such as neighbouring buildings can limit daylight access from several windows in a room. Internal obstructions, such as columns, may also limit the point access to daylight.
  • Windows and roof lights: the location of windows, glazing to floor area ratio, and visible light transmittance value of glazing have a major influence on the daylighting performance of a room.
  • Shadingexternal shading devices or screens, if not properly designed, could reduce daylight access in the room. Shadings must be properly designed for specific climates to have a small impact on daylighting performance while reducing cooling demand as much as possible.
  • Internal finishes: use of light-coloured flooring and linings, increases the reflectance of daylight in a room, contributing to a better distribution of daylight in the room.