Existing buildings or portions thereof presently used for residential purposes may continue to be occupied for residential purposes if:
(a) The building complies with the provisions of this Housing Code except as to any variance heretofore specifically granted by the Village; and
(b) The use and occupancy of the building is not, or at the time of construction or alteration was not, in violation of any provision of the ordinances of the Village and applicable statutes of the State, including any rules and regulations adopted pursuant to such ordinances or statutes.