Lighting layers in a room

Ambient lighting supports orientation, task lighting supports an activity, and accent lighting creates hierarchy and atmosphere. The calculator establishes a quantitative base, while good design usually combines several layers.

Practical example

A 20 m² room with a 150 lx target needs 3,000 lumens reaching the plane. With UF 0.65 and MF 0.80, the sources need about 5,769 lm. Six 1,000 lm fixtures give an estimated 156 lx.

Limitations

The simplified model does not know fixture intensity curves, individual surface reflectance, obstacles, glare or uniformity. A construction-ready design requires photometric data and suitable software.