A fundamental challenge for today and the future is the preservation of existing constructions. In addition to repair and maintenance measures, the effective strengthening of existing structures is of central importance to this issue. According to current regulations, a large number of existing reinforced concrete (RC) structures show deficits in their shear capacity, which is often limited by their existing shear reinforcement. The application of thin carbon reinforced concrete (CRC) layers can be a suitable and effective alternative to previously used strengthening methods. In this study, two RC T beam types, which differed in cross-section, were strengthened with CRC. The essential parameters of the strengthening layers were varied, and the influence of these changes on the load-bearing behavior and shear capacity of the T-beams was analyzed. Compared to non-strengthened test specimens, load increases of about 40% were achieved in the CRC-strengthened T beams.