Daylighting in hospital patient rooms: Parametric workflow and genetic algorithms for an optimum façade design

Abstract

Daylighting and access to external view in hospital patient rooms can positively contribute to patients' healing and improve staff performance. This paper introduced a parametric workflow and optimization for generating and evaluating alternative façade configurations. The approach developed in this study manipulated the external wall façade at efficient inclination angles and changed window distribution for the optimization of daylighting of a south oriented patient room under the desert clear-sky of Cairo, Egypt. Grasshopper, a parametric modelling tool was used to automate the daylighting simulation process. Daylight analysis was performed by the use of Divafor- Rhino plugin via integration with Radiance and Daysim software. A genetic algorithm was used to generate and evaluate the performance of the most successful solutions by automatically adjusting different variables through control nodes until near optimum solutions were reached. Results demonstrated that parametric workflows and optimization can be effectively used to generate unconventional patient room façade designs that provide superior daylighting performance. The approach proposed in this study produced a wide range of unconventional façade designs that achieved 100% daylit area on both the bed area and the room area, with 0% of partially-daylit and over lit areas.