This paper investigated the behaviour of locally post-tensioned nail laminated high mass floor panels. Each panel was assembled using butt jointed timber boards. Post tensioning was applied using bracing straps. A total of six panels were tested under four-point bending. The dynamic behaviour of the floor panels was also investigated Results showed that post-tensioning reduced the deflection by almost 50% under the serviceability loading condition. However, the damping ratio was reduced under dynamic tests, though it remained within acceptable limits.