Thesis presents the calculation of static and strength of a wooden roof, built of spruce wood. The basic strength properties of wood and strength classes, important for the design of timber structures, are presented. The basis for the calculation is the triangular king post truss with rafters being attached to it. The dimensions of individual structural elements bearing the load, are verified as foreseen by Eurocode standard (dead load, live load, snow load, wind load). Internal voltage and deformations of load-bearing elements are generated by TOWER 6.0 DEMO computer programme, considering impacts on the structure by Eurocode methodology. Dimensioning is based on the method of limit state load (MSN) and the method of the marginal status utility (MSU). Analysis itself shows that the structure is constructed safely, but in terms of consumption of material very wastefully. In the analysis it was found that we needed a timber classified in the strength classes. Because of complexity of Eurocode system it is necessary to use modern computing devices and computer programmes. It is also necessary to know a number of other standards, related to Eurocodes.