Exhaustion of natural aggregates is one of the growing problems in the construction industry today. As such, this study examined the effectiveness of pulverized mud crab shells (PMCS) as partial fine aggregate substitutes in producing concrete roof tile. There were three set-ups of differing percentages of PMCS (0%, 10% and 15%) in this study. The samples were compared through their physical and mechanical properties. Properties assessed include permeability test, water absorption test and flexural strength test. One-Way Chi-Square was utilized for permeability test while in water absorption test and flexural strength test, One-Way ANOVA was utilized. The results revealed that in the permeability test, all three set-ups passed the standard requirement with three samples each achieved with no water leaking for 24 h. All five samples with 15% PMCS passed the permeability test. Also, all three groups of samples passed the water absorption test with less than 5% of water absorbed. The samples with 10% PMCS had the least water absorbed. The sample with 15% PMCS obtained the maximum flexural load. Cost-benefit analysis showed that the sample with 15% PMCS was the most expensive. Although the production was not cost-efficient, its benefits still outweighed the costs. The results conclude that PMCS could be utilized as partial replacement to sand in manufacturing concrete roof tile with 15% PMCS being the most suitable and adequate replacement. Thus, it is recommended to implement by batch production of all the samples with the same mix and proportion to achieve uniformity among the samples. In addition, it is encouraged to add more set-ups of varying PMCS percentages to achieve better data comparison and results.