The Multigap Resistive Plate Chamber (MRPC) is used in many experiments due to its excellent efficiency and time resolution. We have studied the ageing effect on MRPC's glass sheets. In particular we analysed an MRPC built with glass sheets that had been used for ten years in a cosmic ray study. We extracted the glass sheets from these old chambers and built a new MRPC chamber. We used different configurations; significant changes in the efficiency and time resolution have been observed.