Myself and my neighbour had a timber fence installed in April, and now all of the 6' 4x4 posts have large cracks running down the grain, up to 5mm wide and 20mm deep. We are meeting the contractor to discuss it but he says that some cracks are inevitable as wood is a natural material. I've never seen fencepost cracks like this - any idea what went wrong?
The timber was pressure treated.
Chris