Where two (2) or more contiguous substandard lots of record or parts of lots of record are in common ownership and are of such size as to constitute at least one conforming "zoning lot", such lots of record or portions thereof shall be joined, developed and used jointly for the purpose of forming an effective and conforming zoning lot(s). Such contiguous substandard lots of record in common ownership on the effective date hereof shall be considered jointly thereafter as being a single parcel, lot or zoning lot for the purposes of this title. (1965 Code title 6 § 301.0)