One-dimensional water transport in cores of different concrete types with a moulded surface at one end was investigated by the simple measurement of mass changes during suction and by evaporation tests. Non-destructive methods (magnetic resonance imaging (MRI) and x-ray tomography) were applied successfully to the localization of water distribution within the concrete during such tests. Before the suction test was carried out, all samples were stored for 18 months under constant climatic conditions (35% RH, 70% RH, or 90% RH) to avoid inhomogeneous humidity distributions. They were then sealed with aluminium tape (epoxy in the MRI measurement) on all faces except the moulded surface, thus guaranteeing one-dimensional flow.