The aim of the study was to assess the load-bearing capacity of a perforated thin-walled beam cooperating with a particleboard in a structural system. To this end, numerical simulations were conducted using the finite element method (FEM), taking into account geometric and material nonlinearities as well as contact between the beam and the board. The numerical model was validated based on laboratory tests for two spans (3 m and 6 m). The simulations enabled the determination of load-bearing curves depending on the span of the system and the identification of failure mechanisms. The results of the model closely matched the experimental outcomes, confirming its reliability and usefulness for further structural analyses.