For hydration curing, CMUs with 15% eco-admixture displayed a slightly lower strength compared to OPC-H at both testing ages. To be more specific, it was 13% lower at age of 1 day and 10% lower at age of 28 days. The strength requirements from Canadian CSA and U.S. ASTM standards for load-bearing CMUs are 15 MPa and 13.8 MPa respectively.