Impact of model detail on daylighting metrics in residential buildings

Abstract

Daylight metrics that shall guide performance-driven design must be applicable to models that reflect the limited knowledge at the time of planning decisions. In particular in residential buildings, the furnishing is beyond the control of such decisions and therefore unknown in the planning phase. The impact of model detail on illuminance- and luminance-based metrics is tested on a residential unit in Singapore. At two elevations, representing a work-plane and the eye level of a standing inhabitant, the metrics are computed from a) a detailed model incorporating furniture and shading devices, b) a model with only shading devices, and c) a minimalist model representing only the design decisions of the architect. As a potential approximation to the detailed model, d) a variant of the minimalist model with wall reflectance reduced to 0.20 is tested. The results for the three levels of detail are compared and indicate the significant impact of detail on all assessed daylight metrics.