Daylighting simulation of japonese architecture using all sky model

There are two purposes for this paper, one is that the calculation method, which took sunlight into consideration using All Sky Model, is shown, and another is executing simulations by this method. The simulations are able to verify the daylighting technique of Japanese traditional architecture. Skylight and sunlight intensity are calculated using All Sky Model. The algorithm of daylight calculation uses the virtual cube, which divided into many grid cells. This cube is placed on a sample point and the illumination at the sample point from each patch is calculated. Calculation of interreflection is executed based on this result of the illuminance. The daylighting simulation of a room was executed by this calculation method. As a result, this simulation confirms us the method often used in traditional Japanese architecture, which is using reflected daylight from garden as indoor illumination.