“Story” means that portion of a building included between the lower surface of any floor and the lower surface of the next floor above it; or, if there is no floor above it, then the space between such floor and the ceiling next above it. If the lowest finished floor level directly above a basement or an unfinished space is more than six feet above the finished grade, such basement or unfinished space, whether open or enclosed, shall be considered a story. (Ord. 89-1 § 1, 1989.)