The calculation of the roof structure for an industrial hall has been carried out. The roof structure consists of main prestressed beams, secondary reinforced concrete beams, and a steel sheet roof covering. The main prestressed beam has an "I" cross-section. Prestressing is performed without the occurrence of cracks. The dimensioning of the prestressed beam and the required number of cables have been completed. Checks of the ultimate limit state and serviceability limit state for the main beam have been conducted. The transfer and anchorage length of the cables and the neutralization of the cables have been determined to ensure that no cracks appear in the beam. The secondary beam has been dimensioned. The selected secondary beam has a reinforced concrete trapezoidal cross-section. The ultimate limit state check for the secondary beam has been performed. Finally, the anchorage lengths and overlapping lengths for both beams for all their reinforcements have been calculated to detail the reinforcement of their cross-sections, and all calculated beams are presented in graphical representations, i.e., drawings.