To give you an idea of what the barrier is cutting off, here's a map of the Main Hall:
Link back to this game
The barrier is mostly outside the Hall and is in straight lines, but got messed up on the east wall (top of map) so it dips and curves and has cut off most of the staircase to the kitchen, and has taken out a chunk of the dais behind the high table.
Bai isn't happy.