Corrugated sheets placed on girders are very often used in industrial construction as roof envelopes. However, their application is sometimes accompanied by failures namely both from dewatering point of view and heat-moisture regime in roof envelope. As example is demonstrated the roofing of steel hall with saddle roof and parapet and valley gutters which is analyse in this paper. The paper is also documented by the calculation of rainwater-flow by deflected gutter and it is completed by the design of maintenance.



