Timber engineering is currently crossing new frontiers in terms of performance, as illustrated by the increasing number of high-rise buildings. This has been made possible by high performance joints, as for example glued-in rods (GiR), and innovative engineered wood products, such as cross-laminated timber (CLT). This paper sheds light onto the mechanical behaviour of GiR joints in CLT by numerically modelling, setting the focus on the prediction of the joint load-carrying capacity, for which very few data is currently available. The analyses are based on extensive experimental testing of GiR joints. In a first step, the relevant material strength properties are characterised, with a particular focus on the timber. Then, a 3D numerical model is built, based upon which the influence of rod diameter and anchorage length on the distribution of shear and transverse normal stresses is illustrated. Lastly, both mean and lower 5%-quantile GiR joint load-carrying capacities of each of the eight experimental test series are predicted using a well-established probabilistic method, resulting in a very good agreement with experimental data.