Investigating the effect of daylight on seating preferences in an open-plan space: A comparison of methods

As a dynamic element revealing architectural space, daylight not only provides substantial illumination but may also influence how occupants interact with the space. This thesis investigates one aspect of interaction, whether there is an effect of daylight on seat choice behaviour. Previous studies have provided limited evidence of an association between daylight and seating preferences of individuals, in part because each study employed different methods to measure and quantify seating preferences of individuals. This concern is compounded by the fact that previous research has tended to use a unique set of daylight metrics in addition to a unique set of measurement points in the test space. This raises the discussion as to the method by which daylighting conditions were evaluated and the procedure with which seating preferences were sought.

This study used two procedures to examine whether daylight affects seating preferences in an open plan room. The first was a stated preference approach in which individuals were asked to indicate the factors they perceived to influence their choice of seat location. Responses were sought from both those who were about to enter the room and those who were already seated in the room. Daylight was suggested to be the most important factor amongst those respondents already seated in the room, but was less important among those people who responded at the entrance.

The second was a revealed preference approach which draws inferences on seating preferences from the actual choices made by individuals in the test room. The data were collected using two methods. One was a snapshot method, recording actual seating behaviour of individuals at regular intervals and the other was a walk-through method, following individuals from the moment they entered the room until they chose a seat. The influence of daylight was investigated using a dynamic simulation modelling method to predict daylight illuminance in the test space. The method was to derive a set of daylight metrics for each individual seat over the observation period. Results showed that higher illuminances led to increased seat occupancy, but only in close proximity to windows. It was found that using a questionnaire to ask people about their seat choice when already seated led to the suggestion that daylight had stronger influence than was found in the revealed preference approach.