Daylight Simulation

Please consider the adoption of Useful Daylight Illuminance (UDI) for the daylight simulation metric. This annual metric acknolwedges both a lower and upper bound of usable daylight. Spatial Dayligth Autonomy (sDA) only measures daylight above a minimum and artibrarily assigns 50% as an acceptable level of occupied hours to exceed this minimum value. Then, ASE is used to examine potential glare but a threshold of 1000 lx is woefully inadequate to represent glare. In the indoor environment, the human eye can tolerate illuminance levels up to 3000-5000 lx, which why this is often the upper range of the UDI threshold. Further, direct sun will often have illuminance values above 10,000 lx on a horiztonal surface. So, by adopting UDI you can rely on a single annual metric that respects both dim and bright conditions.