Veranda as one of the main elements of spatial hierarchy in the traditional Iranian architecture is responsible for providing visual and thermal comfort and energy saving, in the interior and to some extent exterior besides enhancing both the privacy and accessibility as a transition space all around the building. In the Solar Decathlon China 2013 (SDC 2013) house of Team Iran, the roof of veranda has been designed to be a functional part of the above goals. It is composed of several reflector pieces gathered in each veranda frame forming a traditional Iranian pattern. In the southern veranda roof, the reflector pieces are able to rotate on a daily basis, based on the amount of interior light intensity and optimal function of the water wall located in the southern facade. Through the current article this particular veranda design and its detailed mechanisms are thoroughly discussed. Lighting simulations have been performed for the interior of the house, with and without the veranda, in addition to covering different states through the day during distinct seasonal conditions for five specified geometrical layouts in the former case. Meanwhile, a data reduction procedure has been applied and validated by the obtained data in order to get an overall numerical interpretation of each case. The results confirm that the original width between the pattern elements in the traditional layout forms the optimum configuration and the rotation mechanism in the southern veranda roof further enhances the interior visual comfort.