The current experimental work was designed and implemented to find the optimal strengthening solution for increasing the flexural load-carrying capacity of structural reinforced concrete (RC) cantilever elements such as RC balconies. This was achieved through the use of innovative L-shaped CFRP ribbed bars (CutInov) with minimal destruction in limited spaces. The CFRP bars are composed of a horizontal extremity, inclined extremity, and transition zone between these two parts. The horizontal part is installed according to the near-surface mounted (NSM) technique, while the inclined part is installed according to the embedded through section (ETS) technique. The inclined part can have different inclinations; however, the higher the inclination, the larger the stress concentration in the transition zone. To assess the flexural strengthening performance of these CFRP bars in balcony-type structures, an experimental program composed of eight RC balcony prototypes was conducted, whereby the specimens were tested under static flexural loading conditions until rupture. This experimental program was designed to assess the influence of the percentage of existing flexural tensile steel bars (two percentages were tested: ρsl = 0.42% and 0.66%) and the inclination of the ETS part of the CutInov CFRP bars (three inclinations were tested: 15°, 30°, and 45°). The strengthening system significantly increased the yield and ultimate load capacity of the balcony prototypes. In the prototypes with ρsl = 0.42%, the CutInov CFRP bars of the ETS parts at 15°, 30°, and 45° provided an increase in the ultimate load of 219%, 176%, and 152%, respectively. In the prototypes with ρsl = 0.66%, the CutInov CFRP bars of the ETS parts at 15°, 30°, and 45° provided an increase in the ultimate load of 104%, 93%, and 90%, respectively. The results demonstrate that the strengthening system efficiency can be improved by reducing the ETS extremity inclination.