Where uncertainty exists with respect to the boundaries of the various districts, as shown on the building zone map attached to the ordinance codified in this title and made a part of this title, the following rules shall apply:
A. The district boundaries are either streets or alleys unless otherwise shown, and where the designation on the map attached to the ordinance codified in this title and made a part of this title indicates that the various districts are approximately bounded by street or alley lines, the streets shall be construed to be the boundary of such district.
B. 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; and where the designation on the map attached to the ordinance codified in this title and made a part of this title indicates that the various districts are approximately bounded by lot lines, the lot lines shall be construed to be the boundary of such district, unless the boundaries are otherwise indicated on the map. (1997 Code § 17.48.100)