Dynamic mechanical spectroscopy and differential scanning calorimetry measurements carried out on PVDF films are reported. Several mechanical relaxations are observed around - 100° C, -40° C, and 17° C at 1 Hz, respectively. It is shown that thermomechanical treatments induce variation of material morphology as revealed by calorimetry and low-frequency mechanical spectroscopy. The effect of long-term ageing at room temperature is attributed to reversible melting and formation of small crystallites. The molecular rearrangements involved in ageing at room temperature are characterized by a slow dynamics.