General dimensional regulations and regulations (as well as
clarifications, notes, and references) specifically referenced to
the tables follow:
A. Building height.
(1) Adjacent to residences. In any zone, required setbacks shall be increased
by one foot for each foot buildings exceed 35 feet in height.
(2) Barns. In the AG District barns may exceed the height limit.
(3) Exceptions. Unless subject to FAA requirements, the height limits
specified in the tables shall not apply to the following: chimneys,
flares, stacks, storage silos, satellite dishes, antennas, elevator
shafts, rooftop mechanical equipment, ventilators, skylights, church
towers, cupolas, domes, pinnacles, spires, silos, water tanks, and
similar elements, provided the combination of the building and element
does not exceed 100 feet in height (unless otherwise specifically
provided for in this chapter).
B. Building separation. Except within the DC Zone, all buildings or
open covered structures situated on the same lot must be separated
from one another by a minimum of 10 feet or as regulated by the New
Hampshire State Building or Fire Code.
C. Building stories.
(1) Floors below grade. Floors with any portion below grade do not count
toward meeting requirements for a minimum number of stories. Any floor
with at least 1/3 of the floor to ceiling space situated at or above
grade shall count toward the maximum number of stories permitted.
(2) Upper floors. Upper story/attic spaces count toward the minimum required
number of stories specified in the dimensional tables if a portion
of the floor area of those upper story/attic spaces equal to at least
1/2 the floor plate of the building has a ceiling height of at least
seven feet.
D. Corner lots. On corner lots, for the purpose of setbacks, there shall
be established a front, a street-side side, a (regular) side, and
a rear. The ordinary front setback shall apply to that section of
the lot which is deemed the front, as determined by the Director of
Building, Zoning, and Licensing Services (based upon the locations
of the front entrance, street address, path to the front, and driveway;
E911 standards; the prevailing pattern of the other buildings on both
blocks; impact upon the streetscapes; and other appropriate factors).
The street-side setback shall apply to that side of the lot facing
the other street. The street-side setback shall be the ordinary side
setback in that district.
E. Density rings. The density rings are shown on the Official City of
Rochester Zoning Map that is adopted as part of this chapter and only
apply to multifamily dwellings/developments. The rings are defined
as follows:
[Amended 2-6-2018; 5-7-2019]
(1)
There is no minimum lot area per dwelling unit applicable within
the Downtown Commercial (DC) Zone District. For areas outside of the
DC Zone District, the minimum lot area per dwelling unit within a
one-mile radius of the center of Rochester shall be 5,000 square feet.
The minimum lot are per dwelling unit outside of the one-mile radius
of the center of Rochester shall be 7,500 square feet.
(2)
The minimum lot area per dwelling unit within a one-half-mile
radius of the center of Gonic and East Rochester shall be 5,000 square
feet. The minimum lot are per dwelling unit outside of the one-half-mile
radius of the center of Gonic and East Rochester, shall be 7,500 square
feet.
(3)
Any lot that is partially within the radius of a density ring
shall be treated as if it were entirely within the radius of the density
ring.
F. Double frontage lots. On double frontage lots, for the purpose of
setbacks, there shall be established a front, two sides, and a rear.
The ordinary front setback shall apply to that section of the lot
which is deemed the front, as determined by the Director of Building,
Zoning, and Licensing Services (based upon the locations of the front
entrance, street address, path to the front, and driveway; E911 standards;
the prevailing pattern of the other buildings on both blocks; impact
upon the streetscapes; and other appropriate factors). The regular
rear setback shall apply to that section of the lot opposite the front.
G. Exempt structures. Nonhabitable utilities and utility-type structures
erected by a governmental, public utility or nonprofit agency which
customarily are built within the road right-of-way, on undersized
lots, or close to property lines, and which cannot reasonably be made
to conform to the requirements of the dimensional tables, are exempt
from those requirements.
H. Frontage and access. Access to lots shall be taken from the same
road where the lot frontage is located unless waived by conditional
use.
I. Frontage.
[Amended at time of adoption of Code (see Ch. 1, General
Provisions, Art. II)]
(1) Continuous. An area used to meet frontage requirements must be continuous
and unbroken. Two or more discrete areas may not be added together
to meet frontage requirements.
(2) Culs-de-sac. The Planning Board may reduce the required frontage
on the curved end portion of a cul-de-sac by up to 20% by conditional
use (due to the narrower frontage relative to lot width that naturally
occurs along a cul-de-sac).
(3) Depth. The front portion of every lot must be at least the width
of the required frontage from the front property line extending back
at least the depth of the setback from the front property line.
J. Lot area; usable area. No lot shall be approved unless a rectangle
measuring at least 3,000 square feet can be fit inside the lot beyond
any required setbacks, wetlands, wetland buffers, or slopes greater
than 25%. The rectangle must be located in an accessible part of the
lot and its width must measure at least 30 feet.
K. Lot coverage. All of the following elements are considered part of
lot coverage: buildings, roofed structures, or impervious surfaces.
L. Multiple principal uses. Where there are multiple principal uses
on one lot or parcel, minimum required lot sizes are not aggregated
except where there are multiple residential uses; i.e., it is necessary
only that the lot size meet the minimum requirement for any use proposed
for the lot. (Example: A certain zoning district stipulates a minimum
lot size of 40,000 square feet for all permitted uses, including single-family
and commercial both of which are allowed. To accommodate a single-family
house and a commercial use on the same lot, a lot 40,000 square feet
would be required, rather than a lot 80,000 square feet. However,
to establish duplexes, townhouses, and apartments on the same lot,
the minimum lot size would be based on the total number of dwelling
units.) Nonetheless, as part of site plan review, the Planning Board
may stipulate appropriate conditions to ensure compatibility of the
multiple uses.
M. Nonconformities, creation of. Except for open space lots and conservation
land, lots and sites may not be created or modified in any manner
that would make them nonconforming in terms of any dimensional requirements
of this chapter.
N. Open space lots; frontage. It is not necessary for open space lots
and conservation land to be in compliance with any requirements of
the dimensional tables. Minimum frontage of 12 feet is required in
order to ensure access.
O. Right-of-way encroachments. Within commercial districts where there
is no minimum front setback, encroachments may occur within the public
right-of-way as follows:
(1)
Footings below grade may encroach as needed subject to approval
of the Director of Building, Zoning, and Licensing Services and Public
Works Department.
(2)
Awnings over the sidewalk provided there is a vertical clearance
of at least seven feet.
(3)
Architectural elements, such as balconies, bay windows, and
cornices, on upper floors provided the encroachment does not exceed
two feet and provided there is a vertical clearance of at least 10
feet.
P. Rounding off. In any calculation, where the final number results
in a fraction of a unit, the number of units shall be rounded up to
the next whole number where the fraction is 1/2 or greater. It shall
be rounded down to the next whole number where the fraction is less
than 1/2.
Q. Setbacks for accessory uses. Setback requirements apply to buildings
and roofed structures accommodating accessory uses in similar fashion
as those accommodating principal uses except where otherwise specified.
R. Setback application.
(1)
Required setbacks apply to buildings, roofed structures, open
air decks, porches, ground-mounted mechanical equipment, ground-mounted
satellite dishes, fuel tanks, and bulkheads. The setback requirement
applies whether the element is a principal or an accessory use. [See
extensions beyond setbacks (i.e., into setback areas) below; special
exception provisions for porches; and several other specific exceptions
and special provisions regarding setbacks in this chapter.]
(2)
Setbacks are measured to the building foundation, except where
a portion of the building containing usable floor area extends beyond
the foundation (such as on the upper floors in a garrison-style house).
Where a building foundation is not present or not applicable, setbacks
are measured to the most appropriate vertical fascia, eave board,
or header joist for that part of the structure. For ground-mounted
mechanical equipment, ground-mounted satellite dishes, fuel tanks,
and bulkheads, setbacks are measured to the nearest part of the structure.
S. Extensions beyond setbacks (i.e., into setback areas).
(1)
Appurtenant elements to buildings or structures which do not contribute to usable floor area and do not have a foundation and which are not specifically included in Subsection
R above may extend into the setback areas but may not extend beyond any property line. This includes, but is not limited to, architectural trim, awnings, bay windows, chimneys, decorative architectural elements, downspouts, window air-conditioning units, exterior steps, fire escapes, gutters, place of refuge decks, building-mounted satellite dishes, roof eaves, siding materials, and vents.
(2)
In cases where any landing serving exterior steps exceeds 24
square feet in area, that landing (but not the steps) must meet all
required setbacks.
T. Triangular lots. Triangular lots shall contain one front lot line
and two side lot lines.
U. Triple frontage lots. On triple frontage lots, for the purpose of
setbacks, there shall be established a front, two sides, and a rear.
The ordinary front setback shall apply to that section of the lot
which is deemed the front, as determined by the Director of Building,
Zoning, and Licensing Services (based upon the locations of the front
entrance, street address, path to the front, and driveway; E911 standards;
the prevailing pattern of the other buildings on both blocks; impact
upon the streetscapes; and other appropriate factors). For any side
which faces a street the setback shall be the ordinary side setback
in that district. The ordinary rear setback shall apply.