Nowadays, the composite pressure vessels are the most mature mode for storing hydrogen at very high pressure. Regardless of the many advantages of the composite pressure vessels, storage under high pressure leads to the use of thick layers of composite, and the behaviour of this type of structure is poorly mastered due to the higher impact of the process on the material-structure behaviour, and especially at the dome area. In order to model the behaviour of composite pressure vessels, in this paper a structuring model of composite pressure vessels is proposed. The structuring model takes into account the variability and specificity of the geometry of the dome area that is considered as the most problematic part of the composite pressure vessels. We integrate in our sizing model properties such as end of helical layers, thickness evolution, winding angle evolution, voids and fibre content.