Visual Comfort Assessment of Different Shading Strategies in a Commercial Office Building in the Southeastern US

It is challenging to design buildings that simultaneously consider both the dynamic nature of daylight and specific occupant preferences. The authors have investigated this problem by studying the performance of four specific shading strategies using quantitative measurements of occupants visual comfort: discomfort glare and daylight availability. This paper specifically evaluates the performance of four shading strategies, two types of electrochromic (EC) glass, an automated fabric roller shade, and a venetian blind in a building located in the Southeastern United States. This paper examines how these technologies impact occupant visual comfort and it also examines how the buildings perform relative to the two metrics outlined in IES LM-83-12. Horizontal illuminance and high dynamic range images were recorded to assess the existing luminous environment in order to better understand the potential of various shading strategies. Calibrated daylighting models were also constructed in DIVA. Our results suggest that perimeter-zone occupants benefits from EC glass as it can reduce more than 40% of glare annually in this zone. Findings from the interior zones are shown that all four shading strategies perform quite similarly in regards to reducing the glare. This study suggest that by providing a designer at early-design-stage with direct information related to the level of daylight availability and glare condition within a space will lead to improve occupant’s visual comfort