Concrete degradation, caused by cracks and fissures, presents a significant sustainability challenge for the construction industry, with direct implications for maintenance costs and CO₂ emissions. This study aimed to develop porous capsules for self-healing concrete applications, employing volcanic aggregates as carrier agents due to their high porosity and mechanical stability. The capsules were produced through vacuum saturation using sodium silicate as a healing agent and coated with polyvinyl alcohol (PVA) as a barrier material to facilitate self-healing in cementitious materials. Capsules with diameters ranging from 2 to 8 mm were characterised through sphericity and circularity measurements, porosity testing, compressive strength analysis, and chemical composition determination using FTIR-ATR spectroscopy. Results showed efficient encapsulation, achieving saturations of up to 53.13%. The addition of 6% PVA coating increased capsule compressive strength from 2.15 to 2.47 MPa, ensuring their survival during the concrete mixing process. In conclusion, the developed capsules demonstrate potential for incorporation into concrete for self-healing applications, thereby extending the service life of structures while simultaneously reducing maintenance costs and CO₂ emissions associated with cement production.