This study investigates waste glass (WG) as an environmentally friendly substitute for natural sand in cement mixtures. Plastering mortars were fabricated by replacing sand with WG at proportions of 10%, 20%, and 30%. X-ray diffraction, Thermogravimetry, Scanning Electron Microscopy, and Energy-dispersive X-ray spectroscopy characterized the mortars. Compressive strength was measured at two ages (7 and 28 days) for WG-containing mortars. Results confirm the suitability of waste glass as a sand replacement in mortars, with the 20% WG sample showing optimal compressive strength, contributing to environmental and economic impact reduction. Thermogravimetric analysis of the 30% WG mortar shows a significant difference in mass loss percentages compared to the reference mortar, losing only 3.65% at 28 days versus 7.85%. Additionally, waste glass increased mortar density, reducing porosity and enhancing structural uniformity. Despite a decrease in compressive strength values, the results remain satisfactory for application in the Civil Construction industry. This comprehensive exploration underscores the potential of waste glass as a sustainable alternative, emphasizing its positive effects on both performance and environmental considerations.