which similar to result obtained by Bravo and de Brito [30] for specimens with 0–20% tire crumb content. This shows that 20% tire crumb mortar can achieve 9.57% higher water absorption than the normal mortar due to the pores created by the tire particles during hydration in the hardened mortar. Further substitution of tire crumb above 20% leads to a reduction in water absorption due to the fact that tire crumb does not absorb water and only the hydrated parts of the matrix retain water.