Moving office onto portacabin on the other side of yard . Told my boss could do a straight run across underground across yard ("that fine ") ,told him it needs to be 600mm depth as we have wagon run over the area (not fine) . Now he's talking about going the longer way round and could i attach to the railing . I've seen many case when runs for sheds or garage s have been screwed to the fence ,but never seen one along a railing.