•Locally resonant metamaterials-based RC metaslabs for broadband flexural vibration control.•Hybrid vibration control behavior integrating local resonance bandgap and vibration isolation.•Numerical models for designing local resonance bandgap and vibration isolation.•Full-scale experiments for validating the proposed technique and analytical models.•Up to 99.94 % reduction in initial four modal responses of the fabricated RC metaslab. In this study, a novel method is introduced, integrating the principles of the local resonance bandgap (LRBG) with vibration isolation techniques to achieve broadband flexural vibration control in plate structures. This methodology employs locally resonant metamaterial units incorporated into a reinforced concrete (RC) slab, making it suitable for real-world engineering applications. Concurrently, the construction specifics associated with this methodology are elucidated. The mechanisms behind LRBG and vibration isolation within the metaslab were examined using numerical analyses. From these analyses, the frequency range conducive for broadband flexural vibration control was estimated, factoring in both material properties and geometric dimensions. Experimental results on a full-scale RC metaslab, measuring 4,200 × 3,000 × 210 mm, validate that the fabricated metaslab introduces a broadband vibration control region attributed to both the LRBG and vibration isolation phenomena. These findings closely align with the numerical estimations. All bending modal responses inherent in the unmodified RC slab were encompassed within this broadband frequency range. Furthermore, the maximal and initial four modal responses of the RC metaslab were attenuated by up to 81.19 %, 99.57 %, 99.94 %, 99.71 %, and 99.79 %, respectively. Display omitted