The diploma thesis presents the technical documentation drawn up for the purposes of the project for building permit acquisition. The design of a five-storey office building was made in accordance with the Eurocode standards. The bearing structure is designed as steel space frames, which run in the longitudinal and transversal direction. Floor and roof structure is designed as a concrete composite slab. Permanent loads, variable loads, seismic and fire loads have been defined and considered in the design. The calculation of internal forces is made by means of the analysis and design software Scia Engineer 2012. The design of the bearing structure is performed by means of a non-linear global analysis by taking into account the second-order theory and geometrical imperfections. Modal response spectrum analysis was carried out in relation to seismic loads. The structure is designed in accordance with the capacity design rules for a high level of ductility. Further, typical joints and foundations have also been designed and fire analysis for fire resistance class R60 was carried out. Within the diploma thesis we have also made dispositional schemes and details of typical joints.