A novel network growth model to construct larger scale fracture systems is developed. Aperture distributions determined by mesoscale geomechanical modelling are also transformed for use in larger scale networks. The precise aperture characterisation of a mesoscale outcrop sample (2 m × 2 m) is obtained by applying boundary stresses using the combined finite-discrete element method (FEMDEM). The scaling behaviour of the rock sample is examined and quantified for different properties (e.g. spatial organisation, length and aperture) using methodologies that employ power law and fractal geometry assumptions. To grow networks, rather than using the conventional stochastic network model, a self-referencing growth algorithm is developed to populate the geologically obtained pattern together with its geomechanically determined apertures. A larger fracture system (~ 50 m × 50 m) is constructed under a recursive scheme using random walkers to nucleate and propagate fractures in larger domains. Permeability of fracture networks grown to various scales is investigated based on flow modelling by the hybrid finite element-finite volume method (FEFVM). To conclude, this paper presents an approach to estimate hydraulic properties of larger scale naturally fractured rock and has implications for upscaling network properties for reservoir simulation, where no representative elementary volume (REV) can be assumed.