No building shall be erected on a lot of less area or of minimum average width less than hereinafter specified by the regulations for the district in which such building is located.

For the purpose of this chapter, the lot area shall be measured from the base setback line and shall be exclusive of the area between the base setback line and the existing property line ultimately to be included in the street.

In determining the minimum average width of a lot such measurement shall be made by a line perpendicular to the line establishing the average depth of the lot, at any point where 1/2 the required minimum area would fall on each side of such line establishing the minimum average width, provided that the frontage at the street line measured by a straight line on a curving frontage shall not be less than 50% of the required average width, whichever is greater.

No lot area shall be reduced by any means so as to create a lot of less than the required size or so that the existing offsets, setbacks, open space or lot area would be reduced below that required by the regulations for the district in which such lot is located.

Where a lot has less land area or width than required for the district in which it is located and was of record at the time of passage of this chapter, such lot may be used for any purpose permitted in such district, subject to the regulations governing substandard lots set forth under Chapter 478, Subdivision of Land, of the Code of the City of Port Washington; provided, however, that in no case shall the setback or offset requirements be reduced except by order of the Zoning Board of Appeals after due hearing, or as otherwise herein provided. The open space requirements in the case of such lot may be reduced without appeal provided the open space is equal to at least 50% of the actual lot area.