Shading of the roof surface directly influences the thermal conditions and thus also the hygrothermal behaviour of the roof construction. Especially in the case of wooden flat roofs, shading can lead to a reduction in drying and therefore taking in account the effects of shading is essential for a moisture-safe design of such roofs. In this paper, possibilities to account for different shading situations in hygrothermal simulations are shown and their influence on the roof structure are discussed.