There is another glitch that not many people know about in the first area on the right side (quick revive side)
First, go into the front room (facing the courtyard and fountain), where all the windows are.
Then, stand about in the doorway, or in that general area and kill yourself.
When you respawn, run jump and crouch underneath the window, in the lowest panel closest to the pipes on the far side of the room.
The zombies go to whereever you died!