This paper discribed the new heat transfer mathematical model created to represent the convective heat transfer of solar radiation from a sunlit window with Venetian room blinds. For the calculation of convective conponent of solar heat gain from a sunlit window, stack effect was introduced to the heat transfer mathematical model. This model was experimentally verified using acutual values measured with the test apparatus. As a result, convective component and shading coefficients that were measured agreed with calculated one and the effectivenes of the model was shown. The relationships between shading coefficients and slat reflectance, incident solar radiation and incident angle were shown by this model.
