AN OCCUPANT-CENTRIC APPROACH TO ASSESS THE IMPACTS OF BUILDING GEOMETRY PARAMETERS ON CIRCADIAN LIGHT DESIGN: A VIEW-BASED ISOVIST ANALYSIS

ABSTRACT This study extends the applicability of using view-based techniques for building science designers focused on architectural daylighting. Through the development of a holistic computer simulation workflow that integrates results from both isovist and lighting simulation tools we question how different office types perform in terms of creating an indoor environment with high circadian potential, vertical lighting and whether an isovist analysis can provide insights into access to windows for daylight availability and views. Six office buildings were simulated in ALFA for Rhino to run the daylighting analyses and the Isovist software to run the isovist analyses. By testing this novel method, the study identified a workflow to assess building zones and workstation locations suitability for achieving specific LEED and WELL buildings credits. Results show that open-plan offices with clustered workstations have higher drift and lower area/perimeter ratios, whereas open-plan cubicle offices create spaces with high occlusivity, smaller vistas, and obstructed lines of sight. These results were applied to compute an equation that correlates occupants’ seated position with sufficient circadian entrainment lighting benchmarks based on a building's geometrical configuration, shape factor, area/perimeter ratio, compactness, and occlusivity. The equation can be further applied to cases that match the study's limitations and conditions to provide quick insights into the circadian daylighting performance of office buildings. This equation is a free alternative to otherwise expensive and time-consuming circadian lighting simulation software, which can be used to test chronobiological lighting in the early design phases or in post-occupancy evaluations.