Abstract This study evaluates the effect upon the compressive strength of ceramic masonry bricks when industrial byproducts known as soot are added. The research includes an analysis of the granulometric properties of the constituent components, performed manually with ASTM C136‐01 screens to determine particle size using apertures sized from large to small; an analysis by XRD of the mineralogical phases present; a compressive strength analysis performed using standard compression testing machinery; and a water absorption measurement calculated according to Colombian Technical Standard: 4017:2015—Methods for the Sampling and Testing of Masonry Elements and other Clay Products. Five trials were performed using different mixtures of clay and soot, at substitution rates of 20%, 30%, 40%, 50%, and 60%. These mixtures were prepared under identical conditions in order to ensure validity of the resulting comparisons. The results showed that bricks with 20%, 30%, 40%, and 50% added soot demonstrated superior structural strength compared to conventional units. Bricks incorporating 60% soot, however, were found to have lower strength and high porosity.