Scoping Study for Daylight Metrics from Luminance Maps

AbstractMetrics of the quantity and quality of daylight are essential for assessing whether buildings provide good (or even adequate) daylighting for the purposes of human health and wellbeing, visual comfort, and energy saving.At present there are only a few metrics of daylight that are used by designers and researchers. Most of these are very simple, they are based on illuminance and they do not have a proven record in research or usage.Luminance maps offer a richer source of data, and the potential to create new types of metric that will more accurately quantify the quantity and quality of daylight. Recent advantages in camera technology make luminance quick and convenient to measure and to record, opening the way to the development of new luminance-based metrics.This report investigates several potential luminance-based daylight metrics, using real data from surveyed spaces. The metrics are assessed for their stability over time, their ease, accuracy and repeatability of measurement, and their variati...