Modified Expanded Polystyrene (MEPS) has emerged as a promising material obtained by heating and shredding Expanded Polystyrene (EPS) to enhance its specific gravity and strength. This study investigates the suitability of MEPS as a partial replacement for coarse and fine aggregates in non-structural lightweight concrete. The substitution levels of MEPS were set at 10%, 20%, and 25% of the total aggregate volume. Cylindrical concrete specimens (10 x 20 cm) and concrete cubes (15 x 15 x 15 cm) were used for the experimentation. Ultrasonic Pulse Velocity (UPV) and Digital Image Correlation (DIC) were performed to evaluate the mechanical properties of the concrete under compressive stress test. Through DIC, the approach to obtain the concrete's properties, including compressive strength, stiffness, elastic modulus, and poisson's ratio, were obtained. The results demonstrated that the concrete mixture with 20% MEPS substitution exhibited the most favorable performance. Overall, the use of MEPS as a replacement for aggregates in non-structural lightweight concrete shows promise for optimizing the material's mechanical properties. This study provides valuable insights into sustainable construction practices and contributes to the ongoing research in utilizing innovative materials for enhancing concrete performance.