Abstract
In the process of drying of porous materials there is a moving surface separating the dried and wet areas in the body. This surface is a phase transition, which significantly depends on the properties of the material and the temperature, which is due to the external influence of the drying agent and is a function of coordinates and time, and the movement of boundaries is a consequence of phase transitions. The paper presents the properties of the material, namely: heat capacity, density, thermal conductivity coefficients to be the functions of the porosity of the material, densities and heat capacities of body components.