The article presents a validation method for computationally determined glulam strength values. Using numerically modelled glulam, featuring brittle tensile failure, different load configurations were examined in a computationally performed study. The corresponding bending tests show variations in the bending strength depending on the applied configuration. From physical perspective, these strength variations are caused by the interaction between the actual natural strength variability, changes in the load configuration and/or the member volume and the
brittle material behaviour. A targeted comparison between the apparent strength variations, obtained from the computational procedure on the one hand and a related analytical method on the other hand, leads to almost identical results. The comparison proves therefore that the computational approach reflects the principles of the
size effect according to the Weibull theory with sufficient accuracy. The study generally exemplifies that related analytical methods, if available, are a beneficial tool to verify and validate computational procedures.