Cross-laminated timber (CLT) floors often face vibration challenges in long spans under heavy loads, and improvements in their vibration performance typically focus on achieving composite action. This research evaluates the potential of hybrid CLT-steel composite floors as alternatives to conventional long-span CLT floors. The key parameters analyzed include fundamental frequency, vibration dose value, peak acceleration and velocity, response factor, and root-mean-square acceleration and velocity. These results were compared with predictions from the new Eurocode 5 draft. While the hybrid composite floor’s fundamental frequency was approximately three times higher than that of the CLT floor, its damping was around 60% lower, leading to similar acceleration responses between the two. The findings emphasize that damping, rather than bending stiffness or fundamental frequency, plays a crucial role in the serviceability of hybrid CLT-steel composite floors.