Daylighting in an atrium-type high performance house

Different lighting strategies for an atrium-type high performance house that was developed for the 2013 Solar Decathlon competition in Datong, China are discussed in this paper. Although daylighting may be abundant in an atrium, with large exposed window surfaces, such design is typically avoided in high-performance houses due to the poorer thermal performance of glazing compared to opaque building envelopes. However, advantages of the atrium design exist in different weather conditions and are investigated in this paper. Insights from a Solar Decathlon 2013 project with a central atrium and a high amount of glasses in the external envelope (80 square meters of glasses) are given. The house was designed considering weather of Datong and Worcester, Massachusetts (US). Simulation results obtained with Radiance and Daysim allow assessing different parameters such as the daylight autonomy index and the useful daylight index. The challenge of visual comfort for a house with such a great quantity of windows is realized considering different parameters related to the visual glare, including the instant and cumulative daylight glare probability indexes. These glare metrics are often inconsistent as the probability of glare was sometimes depending on the selected index. Different chances to have glare issues resulted using different indices. Finally, the influencing factors for blind adjustments in residential buildings are discussed, and according to these factors and to simulation results with several software, the design of the shading systems and their schedules are evaluated.