All three of these components need to be accounted for to determine the daylight factor. A daylight factor of 2 is a typical level one would want to achieve for an office space. It assumes that 2% of the total light that is outside the building ends up on the working plane or desktop. Assuming an average outdoor illumiance of 2500 foot candles and a daylight factor of 2% the indoor illumiance on your desktop would be 50 foot candles (2% x 2500 foot candles = 50 foot candles). Other typical daylight factors for various spaces are
- Discussion Groups – 14
- Residential Living Room – 1
- Residential Kitchen – 2
- Office – detail work – 4
- Office – drafting – 6
- Office – corridors – 0.5
- Schools – classrooms – 2
- Schools – art rooms – 4
- Hospitals – wards – 1
- Hospitals – waiting rooms – 2
- Sports facilities – 2
- Warehouse – bulk storage – 0.5
- Warehouse – medium size storage – 1
- Warehouse – small item storage – 2