A building or structure or portion thereof occupied by a nonconforming use which is or hereinafter becomes vacant and remains unoccupied by a nonconforming use for a continuous period of one year, shall not thereafter be occupied except by a use which conforms to the use regulations of the district in which it is located. (Ord. 2004-28, 10-20-2004; amd. Ord. 2005-33, 9-21-2005)