The main aim of this research was to analyze how the addition of polymer and wool fibers affects the durability of concrete. Due to the wide range of uses of concrete, more and more companies strive to find solutions to reduce the large amounts of harmful gases produced during concrete production. Therefore, the use of wool, natural and industrially produced fibers is becoming more and more widespread. For the purposes of this thesis, five concrete mixes were mixed, four mixes were made with the addition of polypropylene fibers and one with the addition of wool fibers. Polypropylene fibers were added in percentages of: 0.5%, 1.0%, 1.5% and 2.0%, while the percentage of added wool fibers was 0.5%. After proper care and curing, samples were subjected to the following tests: porosity, resistance to wear by the Böhme method, gas permeability and water permeability. The obtained test results indicate that the use of wool fibers improves the permeability properties. The results of porosity, water permeability and gas permeability tested on the samples with the addition of wool fibers showed better final results with regard to the samples with the addition of polypropylene fibers. It can be concluded that the use of recycled fibers achieves better durability properties of concrete than the concrete without added fibers in it. Looking at natural or industrially produced fibers, natural (wool fibers) dominate over industrial (polypropylene fibers).