In the master thesis, we deal with an engineering practice problem. The subject matter is to assess seismic resistance of an educational facility in Ljubljana. Bearing system of the facility, which was built in the fifties, is mainly made of bricks. Geometric and mechanical features of the existent bearing system were examined by technical documentation and by executing research at the facility. Many destructive, partially destructive and non-destructive research methods were used. Later on a theoretical background is presented, which refers to the seismic analysis of objects made of unreinforced masonry. In the program 3Muri an idealized computational model is presented based on obtained information of the facility. The program is based on the macro elements principle and the non-linear method for seismic performance assessment. Pushover curves, the maximum displacement and acceleration of the bearing system are given as the result of analysis of the structure. According to conditions of the valid standard, the bearing system of the discussed building does not reach the seismic resistance. Later on there are analysed different options for improvement of the seismic resistance of the facility. While designing the strengthening measures it has been taken into account that an extension of the building will be built in the near future. Additional reinforced concrete walls and the future extension of the building are presenting final strengthening measures.