Unless otherwise shown, the district boundaries shall be construed to be parallel to and a specified distance from the center lines of streets, alleys, parkways, waterways, railroad rights-of-way or such lines extended, as noted on plans.

Where such boundaries are indicated as approximately following the property lines of publicly owned lands, such lines shall be construed to be such boundaries.

Measurements stated on the Zoning Map are perpendicular or radial distances from street lines measured to the zone boundary lines, which, in all cases where distances are given, are parallel to the street line.

In all cases where a district boundary divides a lot in one ownership and more than 50% of the area of such lot lies in the less restricted district, the regulations prescribed in this chapter for the less restricted district shall apply to such portion of the more restricted portion of said lot which lies within 30 feet of such district boundary. For purposes of the section, the more restricted district shall be deemed that district which is subject to regulations which prohibit the use intended to be made of said lot or which regulations require higher standards with respect to setback, coverage, yard, screening, landscaping and similar requirements.

In all cases where a district boundary line is located not further than 15 feet away from a lot line of record, such boundary line shall be construed to coincide with such lot line.

In all other cases where dimensions are not shown on the map, the location of boundaries shown on the map shall be determined by the use of the scale appearing thereon.

No building shall be erected, moved, altered, rebuilt or enlarged nor shall any land or buildings be used, designed or arranged to be used for any purpose or in any manner except in conformity with all regulations, requirements and/or restrictions specified in this chapter for the district in which said building or land is located.

No yard or open space required in connection with any building or use shall be considered as providing a required open space for any other building on the same lot or any other lot.

No lot shall be formed from part of a lot already occupied by a building unless such building, all yards and open spaces connected therewith and the remaining lot comply with all requirements prescribed by this chapter for the district in which said lot is located. No permit shall be issued for the erection of a building on any new lot thus created unless such building and lot comply with all the provisions of this chapter.

Nothing contained in this chapter shall require any change in the plans, construction or designated use of a building complying with existing law, a permit for which shall have been duly issued and the construction of which shall have started 90 days before the date of first publication of notice of the public hearing on this chapter, and the ground story framework of which, including the second tier of beams, shall have been completed within six months of the date of the permit, and which entire building shall have been completed in accordance with such plans as have been filed within one year from the day of the passage of this chapter.