Hydrogen deflagration in experimental containment vessels is simulated by introducing a modified Eddy Break Up model, with the aim to apply it for hydrogen combustion in containment vessels. First, an additional term is introduced in the source term of the progress variable (non-dimensional fuel concentration) transport equation to extend its applicability from the turbulent to the quasi-laminar flame propagation region. The model is then modified further by introducing the weighted laminar flame speed, which decreases the influence of this quasi laminar term in the same equation. The models are assessed by simulating two experiments, performed in different large-scale facilities. Simulated axial and radial flame propagation, pressure and pressure increase rate, and flame shapes are compared to experimental results. The comparisons reveal that the model differences affect mostly the simulations in the wider vessel.