To be on file. The Official Zoning Map is an integral part of this chapter. The single official copy of this map, entitled "City of Sheboygan Falls Official Zoning Map," and all amendments thereto, together with a copy of this chapter, shall be kept at the office of the City Clerk and shall be certified by the Mayor and attested by the City Clerk. Any changes in zoning district boundaries shall be recorded on the map. No such change shall be effective until so recorded and until a duly certified and attested certificate describing the change is filed with the map.

Street to be boundaries. The district boundaries are either streets or alleys, unless otherwise shown, and where the designation on the map indicates that the various districts are approximately bounded by a street or alley, such street or alley shall be construed to be the district boundary line.

When lot lines shall be boundaries. Where the district boundaries are not otherwise indicated, and where the property has been, or may hereafter be, divided into blocks and lots, the district boundaries shall be construed to be lot lines where the designations on the map are approximately bounded by lot lines, such lot line shall be construed to be the boundary of the district.

Unsubdivided property. In unsubdivided property, the district boundary shown on the map shall be determined by the use of the scale shown on such map.