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 ?
This paper investigates to adequate the daylighting performance in terms of illuminance level (lux) and daylight factor (DF) in low cost high-rise residential building in tropical area.
The most popular and most used formula to measure and analyze day lighting performance in buildings is the percentage daylight factor [1],[2]&[3].
The objective of study is to analysis the influence of light shelf device on the illuminance and daylight factor levels.
For example, "for many years the yardstick metric of the Daylight Factor (DF) was the benchmark metric.
These included all teaching spaces to have a 2% daylight factor as well as the brightly coloured facade windows to create natural ventilation.
And, with the importance of light and the extent of its power to change moods and environments upper most in my mind, I may well continue to venture into the arena of ballast factor, daylight factor, cosine law and even units of luminance.
In this study, daylight availability was predicted using parameters such as daylight factor, daily radiant energy, and sunlight patterns.
LEED requires a minimum daylight factor (DF) of 2% in 75% of all space occupied for critical visual tasks.
Daylight factor is defined as a ratio of interior illuminance at a horizontal point in a building to the un-shaded exterior illuminance on a horizontal surface under a fully overcast sky (a ratio of outside illuminance over inside illuminance).
As an example, for London weather data with a daylight factor of 3%, 250lux (23.
Calculation of daylight factor DF [%] was carried out for the determination of an effect of three different types of window glasses on the indoor daylighting level in the investigated office.