(a) Within the districts established by this Zoning Code or amendments that may later be adopted there exist:
(1) Lots
(2) Structures
(3) Uses of land and/or structures
which were lawful before this Zoning Code was passed or amended but which do not conform to regulations and restrictions under the terms of this Zoning Code or future amendments thereto. It is the intent of this Zoning Code to permit these non-conformities to continue until they are removed, but not to encourage their survival. It is further the intent of this Zoning Code that nonconformities shall not be enlarged upon, expanded or extended, nor be used as grounds for adding other structures or uses prohibited elsewhere in the same district.
(b) Non-conforming uses are declared by this Zoning Code to be incompatible with permitted uses in the districts involved. A non-conforming use of a structure, a non-conforming use of land, or a non-conforming use of structure and land in combination shall not be extended or enlarged after passage of this Zoning Code by attachment on a building or premises of additional signs intended to be seen from off the premises or by the addition of other uses, of a nature which would be prohibited generally in the district involved.
(1969 Code 150.301)