Concrete Masonry Units (CMUs) are widely used for non-load-bearing walls in building construction; however, conventional CMUs are often produced with material properties that exceed the functional requirements of such applications, leading to material inefficiencies. This study developed a Construction Management decision framework for selecting crumb rubber–modified concrete masonry units for non-load-bearing applications. The study evaluated the performance characteristics of conventional and crumb rubber–modified CMUs, with and without steel mesh reinforcement, in terms of density, compressive strength, and strength development. Laboratory results were analyzed and benchmarked against applicable standards for non-load-bearing masonry units. The findings show that crumb rubber modification influences CMU density and compressive strength, producing properties that may be suitable for non-load-bearing applications, while steel mesh reinforcement can enhance mechanical performance. Based on the experimental results and standards-based evaluation, a structured decision framework was developed to support construction managers and engineers in selecting appropriate CMU alternatives for non-load-bearing walls. The study provides a practical decisionsupport tool that links laboratory performance data with construction management requirements.

Keywords: concrete masonry units, crumb rubber modification, non-load-bearing walls, construction management, decision framework