Space, light, and time : prospective analysis of Circadian illumination for health-based daylighting with applications to healthcare architecture

Light in architecture can be studied for its objective or perceptual effects. This thesis describes an objective link between human health and architectural design. Specifically, the link between daylight and human circadian rhythm (as a proxy for health) is explored. The purpose of this thesis is increase understanding about the health effects of daylighting in architecture. Little in the way of rigorous analysis exists in the emerging field of "evidence-based" design; however billions of dollars are committed to healthcare construction in the United States annually. The next generation of hospitals will certainly be guided by "evidence-based" findings, and so a better understanding of daylight's role in human physiology may influence future healthcare architecture. Therefore, the technical problem addressed here is the prospective analysis of architectural design for circadian stimulus potential based on the state of the art in photobiology. This combines lighting intensity, timing, and spectrum. Included in this thesis are specific recommendations for architectural design, which are based on scientific application of biological findings. Guidelines for circadian illumination are developed and applied. Evaluation of lighting sources (i.e. daylighting, artificial lighting) will reveal those elements of each necessary to meet circadian illumination guidelines. Recommendations for architectural designers will follow that describe how building design can maximize the application of daylighting to promote circadian organization, and thus improve the health potential of the built environment. Thesis Supervisor: Marilyne Andersen Title: Assistant Professor of Building Technology