Lux deprivation

Lux Deprivation is the BEEI factor linking soiled or shaded glazing to reduced indoor daylight and its psychological consequences — sub-clinical Seasonal Affective Disorder, lowered mood and wellbeing. It reframes window cleaning as a health and light-quality intervention rather than a cosmetic one: algal filming and grime on north-facing or overshadowed elevations measurably cut transmitted lux, and restoring clarity restores the daylight the occupant's wellbeing depends on. It is part of the Psychologia dataset of environmental-psychological pathologies.