When refurbishing old buildings with timber elements, the main focus is on improving the load-bearing capacity. However, due to their low mass, timber floors are often subjected to excessive vibration, which results in a loss of comfort due to footfall. One possible retrofit solution for old timber floors is the application of a pre-stressed steel wire rope, which applies an axial force to a beam to counteract the maximum deflection under the same load conditions. Therefore, the retrofit design must take into account the change in dynamic behaviour due to the presence of the wire rope reinforcement. This paper focuses on the analysis, from a dynamic point of view, of both the static and comfort contribution of this type of intervention, understood as a reduction in the vibration frequency of the structural system. The study is developed by analysing different schemes in order to evaluate the best configuration in terms of improving the load-bearing capacity and increasing comfort.