In the plots of base shear versus roof displacement, the narrow hysteresis loops of specimen F1 contrast with the apparently more dissipative response ofspecimen F2, as confirmed by the comparison in terms of cumulative dissipated energy. Therefore, panels caused only a contraction of the hysteresis loops, significantly decreasing the displacement capacity of the bare structure for similar maximum loads. A similar trend was observed in terms of local response of beam-column joints because panels partially inhibited the relative slip of the connection system, causing the frame to fail at much lower displacements because of the local failure of its panel-to-structure joints.