For the purpose of this chapter, the Borough of Chambersburg is hereby divided into 11 types of districts, which shall be designated as follows:

The above districts and the boundaries of such districts are hereby established as fully described in "Record of Zoning District Boundaries," kept on file in the office of the Borough Secretary, and as graphically shown on the map titled "Chambersburg Zoning Map." Said record and map are hereby incorporated by reference into this chapter and shall be as much a part of this chapter as if all were fully described herein.

The district boundary lines are, unless otherwise indicated, either the center lines of streets, alleys or such lines extended, or lines parallel thereto, railroad right-of-way lines, natural boundary lines such as streams, and the municipal Borough lines as they exist at the time of enactment of this chapter. Where figures are shown on the Zoning Map between a street and a district boundary line, they indicate that the district boundary line runs parallel to the street center line at a distance therefrom equivalent to the number of feet so indicated.

Where a district boundary line divides a lot which was held in single and separate ownership at the time the boundary line was established, the use regulations applicable to the less restricted district shall extend over the portion of the lot in the more restricted district a distance of not more than 50 feet beyond the district boundary line.

Upon the annexation of any territory to the Borough, the Town Council may add the annexed territory to the Zoning Map by proceeding in the manner set forth in Article XXII of this chapter. After the effective date of the annexation and until the Town Council has added the annexed territory to the Zoning Map, the annexed territory shall be subject to Low-Density Residential District (LDR) regulations.