I live in a building built on a hill with, in order of descension, the 4th floor through the 1st floor, a ground floor, and a terrace floor. The front of the building enters through to the first floor and the back of the building enters through to the terrace floor.
So I guess my points are a) the terrace is the bottom floor which is the opposite of the definition of "terrace" in my opinion and b) it's impossible to leave the building from the "ground floor" without taking a flight of stairs.
So I guess my actual point is yeah Pub we're right the rest of the world is wrong deal with it!