The Effect of Architectural Configurations on the Biological Light Response in Residential Buildings

Abstract: Daylight has beneficial psychological and health effects that range from enhanced alertness, mood improvements, increased productivity, and well-being. Recently, the interest in non-visual (also called biological) effect of light has increased substantially. Yet, a limited number of research has investigated the non-visual effects of light in Nordic climates. The aim of this thesis is to assess the effect of changing the building configuration on the average Biological Light Response (BLR) that would also translate to a proxy for alertness. This research implements a simulation methodology to simulate the BLR on a residential building located in Malmö Sweden. The building was parametrically modelled using Grasshopper plugin in Rhino, while Honeybee, Ladybug, and Lark plugins for Grasshopper were used to develop the BLR simulation workflow. In the BLR simulation method, four days (two equinoxes and solstices) were simulated with their respective sky conditions for an east- and a west-facing apartment. The simulation considered three CIE sky conditions (overcast, intermediate, and clear) with their corresponding Correlated Colour Temperature (CCT). The results of the simulation in circadian illuminance were compared to minimum and maximum thresholds, indicating the required illuminance to reach 0% and 100% BLR respectively. The BLR percentage was then calculated indicating the average alertness level reached in the space. The simulation results of the base case showed that only March and June days reached an average BLR near the set threshold (75% in this case based on previous research). The total average of the four days was approximately 50%. To improve the BLR of current building design, several parameters in the building were varied, and the best configurations were the ones without the balcony and sunspace, as these elements obstruct glazing areas. In conclusion, the BLR simulation workflow enabled a sound evaluation of the non-visual effects of daylight, paving the way for architects to consider the wellbeing aspect related to daylight during the early design stages.