The aim of this paper is to investigate the performance of CLT beams with and without holes loaded in-plane under various loading conditions with special emphasis on shear loading and the in-plane shear behaviour considering the complex internal structure. CLT beams present a much better solution for beams with holes or notches as compared to glued laminated timber beams thanks to its lay-up where tensile forces perpendicular to the beam axis can be transferred by the transversal layers. In order to have in-depth understanding of the local mechanical behaviour in shear stress transfer between laminations, numerical analyses based on 3D-FE models are used.