The evolution of high-rises puts more challenge for achieving indoor visual comfort because the source of getting natural light inside is solely through sidewalls; especially in deep floorplan like office buildings, where visual discomfort is very usual to be experienced. Without any measure taken, it leads to a situation where the illuminance exceeds the comfort requirement next to the window by making an over-lit area which causes glare issues; furthermore, the illuminance decreases in a gradient along the depth leaving illuminance below comfort requirement towards end of the room making under-lit area, which demands use of artificial lighting. This creates an uncontrolled and non-uniform distribution of daylight along the depth. Moreover, daylight is very dynamic in nature that keeps changing along the time, this adds complexity in design; and hence it leads to use of computational design methods.
This research aims to improve visual comfort efficiency of an office space with the help of computational methods by developing a facade system that distributes the daylight to indoor space more uniformly, bringing balance of light intensity between under-lit and over-lit areas of a space to a visually comfortable range or daylit range (300-2000 lux), adapts to various external factors that are responsible for dynamic daylight behaviour; and results in a controlled distribution of daylight throughout the depth of the space for occupant’s comfort. The strategies applied for the design development as computational methods is by mean of parametric modelling, daylight simulation and optimisation.
The study results in a dynamic façade scheme that validates with visual comfort criteria, which also includes evaluation of glare and contrast. The study also covers constructability and feasibility aspects of the proposed scheme. As the final outcome, an average of 88% of working plane is found to be within the daylit range having average illuminance of 561 lux, which is distributed with an average uniformity ratio of 0.57 with minimal risk of glare and contrast; validating that visually comfortable environment is achieved. This further indicates that the use of artificial light can be reduced by 88%, saving equivalent energy consumption concerning artificial lighting.