The City of Mount Vernon is hereby divided into the following classes of districts:
A. 
Residence districts.
R1-7
One-Family Residence
R1-4.5
One-Family Residence
R1-3.6
One-Family Residence
R2-4.5
Two-Family Residence
RMF-6.75
Multifamily Residence
RMF-10
Multifamily Residence
RMF-15
Multifamily Residence
H
Hospital
B. 
Mixed-use districts.
[Amended 4-30-2021, approved 4-30-2021]
MX-1
Commercial Corridor District
MVW
Mount Vernon West Transit Oriented Development Zone
C. 
Nonresidence districts.
NB
Neighborhood Business
OB
Office Business
DB
Downtown Business
CB
Commercial Business
LI-15
Landscaped Industrial
LI-7.5
Landscaped Industrial
I
Industry
D. 
Special zoning districts.
[Amended 11-10-2021, approved 11-11-2021]
R1-TH
One-Family Townhouse Residence
RMF-SC
Multifamily Senior Citizen Housing Floating Overlay Zone
UR-PUD
Urban Renewal Planned Development
PUD-2
Planned Unit Development
PAP
Planned Adjacent Park Zoning District
UR-PUD-S4
South Fourth Avenue-East Third Street Urban Renewal Planned Unit Development Overlay Zone
The boundaries of all districts are hereby established as shown on a map entitled Zoning Map, City of Mount Vernon, New York, dated October 16, 1997, and as may be amended from time to time and certified by the City Clerk, which map accompanies and with all explanatory matter thereon is made part of this chapter. The official copy of this map is kept by the City Clerk, with copies thereof kept by the Department of Planning and Department of Buildings. Unofficial copies at a reduced scale are included with copies of this chapter. Whenever the City Council amends the Zoning Map, the City Clerk shall notify the Commissioner of Planning, who shall cause the amendment to be made to the official copy of the Zoning Map and to the copies kept by the Department of Planning and Department of Buildings.
Where uncertainty exists as to the locations of any boundaries shown on the Zoning Map, the following rules shall apply:
A. 
District boundary lines follow lot lines, streets, municipal boundaries, rights-of-way, railroad rights-of-way or watercourses, or are parallel or perpendicular thereto, unless such district boundary lines are fixed by dimensions, as shown on the Zoning Map.
B. 
Where district boundaries as shown approximately following streets, rights-of-way, railroad rights-of-way or watercourses, the center lines thereof shall be such boundaries.
C. 
Where district boundaries are shown approximately following municipal boundaries or lot lines, such municipal boundaries or lot lines shall be the district boundaries.
D. 
Where district boundary lines divide a lot, the location of any such boundary, if not indicated by dimensions, shall be determined by use of the map scale appearing thereon.
E. 
If the district classification of any property is in question, it shall be deemed to be in the most restrictive adjoining district.
Where zoning districts are referred to as "more restrictive" or "less restrictive," the designations shall refer to the order in which the districts are named in Chapter 267, Article III, the first named being the most restrictive.
Where a lot in one ownership of record is divided by one or more district boundary lines, the following shall apply:
A. 
Uses permitted in one district may not extend into another district where they would not otherwise be permitted.
B. 
Dimensional requirements shall be measured from the lot lines and not zoning district lines.