The microstructural characteristics of sintered clay ceramics depend mainly on the clay type and thermal transformations. Different pore morphology and connectivity change the liquid water flow process through the material, as in the case of roof tiles which are progressively saturated with water during rain. In this study, 2 clays mined in Burkina Faso are used for manufacturing roof tiles. The major phases detected by X-ray diffraction in the two clays are kaolinite, illite, smectite, quartz and feldspar. The thermal behavior of clays by DTA and TG between 25° C and 1100° C is mainly related to individual roles of clay minerals. During sintering, dilatometry curves show successive densification stages in variable temperature ranges, as a function of clay mineral fractions in compositions. It explains differences in microstrutural characteristics and pore structure. The simulation of the capillary …