Biocomposites are (once again) capturing our imagination with their potential applications: engineered timbers, such as glu-lam and laminated veneer lumber, are being used for the construction high-rise buildings [1], and plant fibre biocomposites have become go-to material solutions for automotive interior components [2]. The efficient impregnation of timber and natural fibre reinforcements with fluids, such as preservative chemicals and polymer matrices, is necessary to produce biocomposites with robust performance. However, modelling and characterisation of these biocomposites has remained a challenge [2-5].