The research object is a novel method for evaluating the self-healing capacity of cementitious composites incorporating cementitious capillary crystalline waterproofing (CCCW) admixtures, specifically using cement paste and concrete specimens with artificially created through-channels simulating cracks. The research method involves preparing cylindrical specimens (26 mm diameter, 140 mm height) with a controlled 0.4 mm diameter axial channel formed by a removable polyamide-6 string, followed by qualitative (visual air bubble observation) and quantitative permeability assessments after 65 days of wet curing, employing the BB-2 vacuum device for air permeability and the UVF-6 installation for water penetration depth under pressure in accordance with GOST 12730.5. The results demonstrate that specimens with the CCCW admixture (Krystaline Add1) exhibited significant self-healing, with specific compositions achieving a water resistance grade of W8 and partial or complete channel sealing.