The effect of moisture on materials leads to changes in their physical and chemicalproperties. Materials with different porosities are saturated by various mechanisms. Thispaper is focused on water transport or diffusion in various porous structures. The Hot-BallMethod is used for determining the water content in certain parts of a specimen. Theprocess of water transport or water diffusion is closely related to a porous structure.Porosity affects the transport properties of a material; therefore, knowledge of themechanisms distributing the water in materials with different porosities is very important.The measurements were carried out by thermal conductivity sensors (hot-ball sensor)located in different positions along the path of the water’s movement. The principle of thehot-ball sensor (thermal conductivity sensor) is based on the Hot-Ball Method formeasuring thermal conductivity. The local moisture content and local temperature ofa porous stone is inspected using the Hot-Ball Method, where the measured values of thethermal conductivity are correlated with the water content. The experimental set up for theinvestigation of the water diffusion in stones is described.
