"Shortened" grass walls becomes full length after loading saved game

[palpie1980]

I have a grass wall. On top of it there are kind of "battlements" looking. If I build stairs leading up to the top of the wall, the "battlements" are cut of and the wall fits nicely under the stair's height.

If I save and then load the game the wall has become full height with the "battlements" and I have to jump to get past it when I walk up the stairs.