The influence of the addition of fly ash obtained from coal combustion as a partial substitute of feldspar on the properties of ceramic tile supports has been evaluated. Clays and other paste additives were characterized by DRX and FRX. The designed prototypes were pressed, dried and fired, evaluating their physical properties (dry and fired shrinkage, apparent density, water absorption) and mechanical properties (flexural strength) and compared to standard cooked specimens. The results indicated that compositions with a high content of fly ash caused a decrease in dimensional changes after firing, density and flexural strength with additions up to 10%; However, with a total replacement of feldspar by fly ash, lower water absorption, lower contraction values and higher flexural strength were obtained, but with superficial defects. Based on the results obtained, it is concluded that the fly ash from the thermoelectric plant at Termotasajero under the working conditions are effective in reducing the density of ceramic products, reducing the cost of transportation and representing a way to recycle an industrial waste generated Pollution problems year after year.