The present work describes the viability of a mortar binder based on two industrial by-products: poly(vinyl chloride) (PVC) particles from scrap and anhydrite (CaSO₄) from fluorgypsum. Mortar composites were made incorporating different amounts of PVC particles and cured at constant room temperature during various periods of time. From X-ray diffraction, it was possible to follow the hydration process and to estimate the effect of the PVC particles on anhydrite transformation to gypsum (CaSO₄·2H₂O). Compressive strength from uniaxial testing was measured from stress-strain curves carried out at room temperature. According to these results, the hydration rates of the composites depend on the concentration of PVC particles and there is an enhancement in their compressive strength as particle content increases, reaching values of 36 MPa after 28 days.