Monitoring Occupant Preferences for Daylight Levels in Indian Homes: A Case of Ahmedabad

Increasingly, researchers are finding and reporting on the critical role of daylight access in human health and well-being. However, the need for visual privacy, controlling direct sun and glare may cause occupants may have to curtail their daylight access from time to time. Existing research has shown that occupants exercise a large degree of control over their home’s energy use. This paper presents results from a field study of homes in Ahmedabad (hot and dry climate) to estimate the degree of control that occupants exercise on daylight levels in their homes. Eleven homes were monitored for a week for daylight levels received in the living room, use of electric lighting, and activities that have been carried out by occupants. Potential interventions (intentional and unintended) by the occupants, such as using curtains and blinds have been treated as occupant behavioral traits that may impede daylight access. The ideal daylight access of homes was estimated using computer simulation and then it was compared to observations in the field study to estimate the reduction in daylight access brought by the occupant(s). This study reveals the extent of trade-offs that occupants have to make for their daylight access and the occupant's comfort in their living rooms.