Therefore, deformation may build up until it exceeds a certain value, and brittle failure of the member may then occur. It should be added that it is usually the limiting strain that generates the amount or size of reinforcement. However, it may also happen that it is not the stress or strain limit state criteria that are decisive in the design process but rather factors such as fatigue resistance and resistance to sudden member rupture resulting from creep. In steel-reinforced structures, on the other hand, it is practically always this ultimate limit state that is decisive. Equally, it should be noted that the strength of a composite bar decreases as its diameter increases, and this is unheard of in steel bars. This paper presents another alternative method of strengthening timber beams using steel and basalt and glass in the form of prestressed bars. This study aims to investigate the effectiveness of the reinforcement, which can then be applied to all types of timber beams. A tension force of 10 MPa was applied to the reinforced bars, corresponding to approximately 2% of the ultimate tensile strength of steel, as the element with the lowest tensile strength. In addition, the load capacity of the beams, stiffness values, and MR as a function of mid-span deflection and failure mechanisms were analyzed experimentally. FEM numerical models were also used to compare the results to the experimental studies. In this study, the main objective was to show the differences in static work after using different fibers and steel. It should be noted that basalt and glass fibers achieve the highest tensile strength as well as all fibers having a tensile strength higher than steel. Glass fibers have surprisingly good wettability through polymers, so the resin adheres easily to them, while the number of air voids at the interface between the materials is negligible. Therefore, very good adhesion can be obtained between fibers and the polymeric material. Glass fibers are also characterized by their high tensile strength or lack of electrical conductivity as well as low thermal expansion. They also have disadvantages, such as the fact that their tensile strength and modulus of elasticity decrease at elevated temperatures. Glass fibers also tend to creep under long-term loading, their strength decreases over time, and they have less corrosion resistance than other fiber types. However, these disadvantages can be mitigated using hybrid bars through the right selection of component materials. Because of the cheap cost of these bars, they are the most widely used material in construction. Basalt fibers, on the other hand, are a single-component material obtained by melting solidified volcanic lava. These fibers already have better physical and mechanical properties than glass fibers and are also relatively cheap. For this reason, along with glass fibers, they are also the most widely used raw materials for composite bars. It should be noted that the main positive characteristics of these fibers include high fire resistance, high sound insulation, high fatigue strength, and internal vibration damping capability. It should also be noted that these fibers have a fiber operating temperature of 982 \({}^{\circ}\)C; a fiber melting point of 1450 \({}^{\circ}\)C; high hardness; and high resistance to corrosion, including acid and alkaline corrosion, which is very important when compared to steel. FRP fibers are characterized by their high strength and stiffness and yet low weight and size. In addition, GFRP rods have a lower elastic modulus, while BFRP rods have a higher one. This is because composite fibers have the most important role in determining the elastic modulus of FRP bars. In addition, all FRP bars have a lower modulus of elasticity than steel, which is related to the fact that it has poorer resistance to the effects of creep. In composite materials, fibers have much better resistance to high temperatures than the resin surrounding them.