This paper used the existing formulae in estimating resistance parameter of reinforced concrete structure to assess the effect of concrete produced from pit-sand in Akure metropolis, on the resistance parameters of a collapsed building in Oba-Ile, Akure. Site inspections were carried out on the collapsed building, and concrete samples were taken. Both destructive and non-destructive methods were used to determine the structure's concrete strength. The number of reinforcements in each structural element was determined by exposing them. Resistance parameters such as moments of resistance for slab (MRS), for beam (MRB) and shear capacity (VC) of the structural elements were estimated using existing formulae and, compare the results with the structure's actual resistance parameters. The average concrete strength was 8.5 N/mm 2 which was less than 20 N/mm 2 , the prescribed concrete strength for construction of the building. The estimated resistance parameters MRS, MRB and VC based on 8.