The daylit area – Correlating architectural student assessments with current and emerging daylight availability metrics

This paper proposes a method for testing current and emerging daylight availability metrics such as daylighting factor, daylight autonomy, useful daylight illuminance and LEED 3.0 requirements against building occupant assessments of a daylit space. During spring 2011 the method was tested as a classroom exercise by 60 architectural students enrolled in two graduate-level building science courses in the 2nd floor studio space of le Corbusier’s Carpenter Center in Cambridge, MA, USA. The results from this test yielded that the Lighting Measurement protocol for Spatial Daylight Autonomy, that is current being developed by the Illuminating Engineering Society of North America (IESNA) daylighting metrics committee, reproduced the student assessments of the daylit area in the space more reliably than the other tested daylight availability metrics. These findings are preliminary and still need to be validated and refined in other spaces. Apart from providing valuable data points for scientific experiments, the method also has substantial educational value as a teaching exercise for architectural students to develop an intuitive understanding of contemporary daylight performance metrics, as well as a feeling of how their personal lighting preferences compare to these metrics.