Non-conforming lots of record shall be used or developed only in accordance with the following:
   (a)   Residential Development of Single Non-Conforming Lots of Record:  In any district in which single family dwellings are permitted, a single-family dwelling and customary accessory buildings may be erected on any lot of record at the effective date of adoption or amendment of this Zoning Regulation, notwithstanding limitations imposed by other provision of this Zoning Regulation. Such lot must be in separate ownership and not of contiguous frontage with other lots in the same ownership. This provision shall apply even though such lot fails to meet the requirements for the area, width, or both, that are generally applicable in the district, provided that yard dimensions and requirements other than those applying to area, width, or both of the lot shall conform to the regulations for the district in which such lot is located. Variance of yard requirements shall be obtained only through action of the Board of Zoning Appeals.
   (b)   Non-Conforming Lots of Record in Combination: If two or more lots or a combination of lots and portions of lots with contiguous frontage in single ownership are of record at the time of amendment of this Zoning Regulation and if all or part of the lots with no buildings do not meet the requirements established for lot width and area, the lands involved shall be considered to be an undivided parcel for the purpose of this Zoning Regulation and no part of said parcel shall be used or sold in a manner which diminishes compliance with lot width or area requirements established by this Zoning Regulation nor shall any division of any parcel be made which creates a lot with a width or area below the requirements stated in this Zoning Regulation.