Paul Violet

If I can jump on the tail of this topic: Had a couple of ceilings over skimmed that were maybe 30 years old with no visible signs of cracking. Just the rest of the house had been updated most of it re-boarded and new stud walls etc so thought these might as well be "freshened up". This was about 5 months ago house has been stood empty while work ongoing. The over skimmed ceilings were primed with SBR before being plastered. They have now started to crack in a few place one all the way across a bedroom but not in the direction of the joists but right angle to them. Any thoughts before I maybe resort to putting a false ceiling in??? TIA