The importance of interior daylight distribution in buildings on overall energy performance

Simulations of daylight distribution within a house show that there can be significant visual discomfort associated with specific sky conditions. Thermal models of the same building, which include simplified daylight calculations and which calculate annual energy performance of the building, do not reflect extreme visual discomfort and high thermal load associated with these sky conditions. These results illustrate the importance of more detailed interior daylight distribution calculations in assessing the thermal and visual comfort of a building, and in developing energy performance ratings for buildings. Some techniques for incorporating more detailed interior daylight distribution calculations in simplified thermal models are discussed.