Cementitious grouts are cement based materials containing fine aggregates that can be modified using organic polymers. During hydration of the cement, the grout will harden to a rigid material. Such grouts are available with different particle sizes and granulometry. Special microfine cements are very common for pre- and post- injection use, as they are able to fill and penetrate smaller cracks and voids than ordinary portland cement based grouts.

Cementitious grouts usually are a cost effective injection solution and the flowability and curing time can be adjusted by the use of admixtures. However, in case of high water ingress, wash-outs can occur and setting might be delayed or hindered due to the dilution effect in very wet strata.