daylight factor

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factor, daylight

The ratio of daylight illuminance received at a given point inside a room to the simultaneous illuminance on a horizontal plane outside exposed to an unobstructed sky. It is usually expressed as a percentage, 5% or more being considered a well-lit room.
References in periodicals archive ?
Realistically, there is no uniform sky that is uniformly illuminated so that values of the percentage daylight factor in building spaces can be directly measured.
In the field work daylight factor calculations ie Le/Lo X 100 and Lw/Lo X 100 the readings which were seen to have the influence of direct sunlight were disregarded.
It found that by providing daylight via skylights, the total glazing area could be reduced, on average, from a maximum 20 percent of floor area to 12 percent of floor area while achieving the same baseline average of daylight factor target of five percent.
The performance of building for daylighting is commonly evaluated regarding to daylight factor (DF), through themethod of daylight factor accepted several years ago by the Commission International de l'Eclairage.
Below we present the daylight factor and the daily total radiant energy of the courtyard space.
For the simulation of this new single zone atrium house, we used Autodesk Ecotect program to calculate the daylight factors in the worst case condition (mid winter at noon) and chose a better fenestration design for the house.
interior surfaces which influence internally reflected component of the daylight factor calculations are: walls with white plaster [rho] = 0.
On the west side of School B, an average daylight factor of 4.
The daylight factor is defined as the ratio of the actual illuminance at a point in a room to the illuminance available from the Commission Internationale de'lEclairage (CIE) overcast sky (Herkel and Pasquay 1997).
0 provides live alerts and estate-wide energy generation monitoring across all renewables investments, with support for multiple sites and taking full account of both weather and daylight factors.
In addition, customers can run several simulation and analysis studies, such as calculating solar availability, determining heating/cooling loads, calculating daylight factors and determining potential ENERGY STAR scoring.
For, while Libeskind would inevitably have tested his compositions himself to understand the visual effect of light falling on internal surfaces (a process which physical models are perfect for as light is scaleless), a more sophisticated animation technique is required for more quantifiable analysis before the lighting consultants can make recommendations to introduce controls where necessary (especially in spaces where the contrasts between low daylight factors and dramatic shafts of direct sunlight are common).