Analysis of daylight metrics based on the daylight autonomy (DLA) and lux illuminance in a real office building atrium in Tehran

A major part of an energy-efficient architecture approach is an atrium that can benefit from daylight as a con-trolling strategy to decrease energy loss. The reflectance characteristic of the surface is one of the main pa-rameters for assessing daylight in an atrium building. Daylight factor was announced as the main variable for depicting different diagrams and deriving some crucial conclusions; meanwhile, other factors such as daylight autonomy could show some significant outputs. Office buildings are as important as residential places for spending time. Hence, saving energy and optical comfort should be managed based on the architectural aspects of a building. Accordingly, herein, the reflectance distribution and Well Index are simultaneously assessed. For obtaining the optimum illuminance, validation and simulation are done based on the real atrium office building in Tehran. The results revealed that the reflectance distribution on a uniform model and a striped model, and geometries of a building could have a significant effect on the vertical daylight outputs. When the reflectance distribution was horizontal with the black color at the top of the wall with a reflectance of 0.02, and one white band under with a reflectance of 0.85, the result is the optimized illuminance and DLA.