What does daylight autonomy mean? How do you calculate the same and how is it different from sDA?
Daylight autonomy is the percentage of time that daylight levels are above a specified target illuminance within a physical space or building for a given duration of time. Mean DA is the average of DA values for the entire daylit area.
Spatial Daylight Autonomy (sDA) is a measure of daylight illuminance sufficiency for a given area, reporting a percentage of floor area that exceeds a specified illuminance level (e.g. 300 lux) for a specified amount of annual hours (e.g. 50% of the hours from 8am-6pm).