The use of all land and every building or portion of a building erected, altered and with respect to height and area, added to or relocated and every use within a building or use accessory in the city shall be in conformity with the provisions of this chapter. Any existing building or structure and any existing use of properties not in conformity with the regulations prescribed shall be regarded as non-conforming, may be continued, extended or changed subject to the special regulations provided with respect to non-conforming properties or uses.
(2001 Code, § 11.01)