NYC Zoning Handbook:
Residence Districts
Chapter 3
Residence districts are designated by the prefix R in the
Zoning Resolution. There are ten standard residence districts
in New York City -- R1 through R10. The numbers refer to the
permitted density (R1 having the lowest density; R10 the
highest) and certain other controls such as required parking.
A second letter or number signifies additional controls in
certain districts. Unless otherwise stated, the regulations
for each of the ten residence districts pertain to all sub-
categories within that district. The R4 district, for
example, encompasses R4-1, R4A and R4B.
Standard Districts
R1 and R2 districts allow only detached single-family
residences and certain community facilities. The R3-2 through
R10 districts accept all types of dwelling units and
community facilities and are distinguished by differing bulk
and density, height and setback, parking, and lot coverage or
open space requirements.
R3-2 districts permit detached and semi-detached houses,
garden apartments, rowhouse developments and a broader range
of community facilities. R4 and RS zones are primarily
districts of rowhouses and small multiple dwellings. The R6
through R9 districts without a letter suffix (R8 rather than
R8A, for example) encourage on-site open space and on-site
parking. These objectives are addressed by a complex formula
involving three variable controls: floor area ratio (FAR),
height factor (HF), and open space ratio (OSR). The Zoning
Resolution assigns a range of floor area ratios in these
districts. The maximum floor area ratio in each district is
reached for a building with a specific height factor in
combination with a specific open space ratio often resulting
in a tall, low-coverage building set back from the
surrounding streets. Although there is no range of floor area
ratios in R10 districts, the tower provisions and the 20
percent floor area bonus for plazas encourage high-rise, low-
coverage buildings set back from the streets. This open space
emphasis in R6 through R10 districts sometimes leads to the
construction of buildings that are out-of-scale with the
surrounding neighborhood, breaking the existing street wall
continuity which characterizes many New York neighborhoods.
Contextual Districts
In 1984, 1987 and again in 1989, the Zoning Resolution was
amended to establish a number of new and revised residential
districts. These districts, generally identified with the
suffix A, B. X or 1 (except R7), are termed contextual
because they maintain the familiar built form and character
of the existing community while providing appropriate
development opportunities.
Lower Density Contextual Districts
In recent years, out-of-scale construction in low-rise
neighborhoods had blurred the distinctions between residence
districts. Sound one- and two-family houses were often
demolished and replaced by larger, multifamily buildings.
There was a need to determine regulations for appropriate new
development in low-rise neighborhoods and to preserve
existing housing. In 1989, New York City enacted the first
comprehensive revision of lower-density zoning since 1961.
Lower density contextual zoning reaffirms the bulk
distinctions, building configurations and narrower lot sizes
of many older residential neighborhoods. By controlling curb
cuts, it also provides more on-street parking and discourages
excessive paving of front yards. It is applicable to low-rise
neighborhoods in the Bronx, Brooklyn, Queens and Staten
Island.
Six new contextual residence districts were created (R2X,
R3A, R4-1, R4A, R4B, R5B) to recognize the particular
characteristics of detached and semi-detached residence and
rowhouse neighborhoods. One existing residence district (R3-
1) was reconfigured as a contextual district and three other
general residence districts (R3-2, R4, R5) were modified to
incorporate elements of lower density contextual zoning.
New requirements were established to maintain the contextual
cohesion of these new and amended districts. All usable
living space, including most enclosed garage and attic space,
must now be counted in floor area calculations. However, in
R2X, R3, R4, R4-1 and R4A districts, a new attic allowance
permits an increase in FAR for floor area under a pitched
roof with headroom between five and eight feet. A new zoning
envelope sets overall building heights for each district as
well as a maximum perimeter wall height, above which pitched
roofs or setbacks are required, to minimize the visual impact
of new buildings on the street. Typically, R3, R4, R4-1 and
R4A districts promote houses with pitched roofs while R4B and
R5B zones are primarily rowhouse districts. Driveways that
run parallel to the side lot line encourage traditional
landscaped front yards and side yard parking in detached and
semi-detached residence districts. Limitations on the width,
number and location of curb cuts maximize on-street parking
and lessen neighborhood parking problems. (For more detailed
information, see Chapter 9.)
Medium and Higher Density Contextual Districts
A major emphasis of the 1961 Zoning Resolution was the
construction of tall, slender buildings surrounded by large,
open spaces. However, new residential development was often
incompatible with the character and configuration of older
neighborhoods. The cost and inefficiencies associated with
construction of these buildings contributed to a slowdown in
housing production. In 1984 and 1987, the Zoning Resolution
was amended to establish a number of contextual districts in
medium and higher density residential areas (R6A, R6B, R7A,
R7B, R7X, R8A, R8B, R8X, R9A, R9X, R10A).
Medium and higher density contextual districts combine
maximum lot coverage with a requirement that buildings be
placed on or near the street line and attain at least a
certain minimum height within the street wall setback
distance. In addition, front and rear sky exposure planes
control the overall height of the buildings. Instead of a
range of floor area ratios to be used in combination with
various height factors and open space ratios, each medium and
higher density contextual district allows the maximum floor
area ratio on a zoning lot irrespective of height factor or
open space ratio. The interaction of the floor area ratio,
lot coverage and street wall requirements results in lower,
bulkier buildings closer to the sidewalk that are in keeping
with the scale and character of the existing neighborhood and
which maintain the traditional streetscape. Because the tower
provisions and plaza bonuses available in R10 districts are
not permitted in R10A districts, new residential development
will be similar in style to buildings in older, built-up
neighborhoods.
Contextual and non-contextual districts treat non-residential
and community facility buildings differently. In non-
contextual districts, residential, non-residential and
community facility buildings are subject to different floor
area ratios and other bulk regulations. In medium and higher
density contextual districts, the space requirements of
community facilities can be adequately accommodated and,
therefore, residential and community facility buildings are
generally subject to similar bulk regulations. However, in
lower density contextual districts, bulk regulations for
residential and community facility buildings usually differ
because community facilities are typically larger than
residential buildings.
Contextual districts also differ from most non-contextual
districts in the way they control the density of residential
development. In the non-contextual R6 through R10 districts,
density is measured in zoning rooms. Each zoning lot is
restricted to a maximum number of zoning rooms. This number
is determined by dividing the area of the zoning lot by the
minimum number of square feet of lot area required for each
zoning room. The minimum square feet of lot area required for
each zoning room varies from district to district it also
depends upon the floor area ratio, height factor and open
space ratio used in the development In the contextual
districts, density is measured in dwelling units. There is
only one lot area requirement in each of these zoning
districts. Each zoning lot is restricted to a maximum number
of dwelling units, a number arrived at by dividing the area
of the zoning lot by the minimum number of square feet of lot
area required per dwelling unit. This allows more flexibility
in laying out the interior of the dwelling units.
Quality Housing
As part of the 1987 amendments to the Zoning Resolution, the
medium and higher density contextual district bulk
regulations were made optional in corresponding non-
contextual districts, and the Quality Housing Program was
established as a mandatory requirement for all residential
buildings developed under the medium and higher density
contextual bulk regulations. The purpose of these amendments
is to encourage development of multifamily housing in a way
that recognizes the relationship between building design and
the quality of life in a dense urban environment.
Under contextual lot coverage, the maximum floor area may be
reached in a building with fewer stories than would be
permitted under non-contextual zoning. For example, in an R7
district, under standard zoning, the maximum FAR of 3.44 is
achieved only in a 14-story building. A six-story building
would have an FAR of 2.88. However, under the contextual
regulations, a six-story building could reach the full 3.44
FAR. In addition, in R6, R7 and R8 districts, on wide streets
outside the Manhattan Core, buildings developed under the
Quality Housing Program may achieve slightly higher FARs.
The Quality Housing Program requires that all developments
built under the medium and higher density contextual bulk
regulations also comply with the four major elements of the
Quality Housing Program: Neighborhood Impact, Recreation
Space, Safety and Security, and Building Interior.
Neighborhood Impact is controlled primarily by the contextual
bulk regulations outlined above, and by street tree planting
and ground floor window requirements. Each of the other three
program elements -- Recreation Space, Safety and Security,
and Building Interior -- have several mandatory components
and some of the components have a two-tier system of
standards (minimum and preferred).
The Recreation Space element establishes minimum and
preferred standards for the amount of equipped indoor and
outdoor space, mandatory regulations for landscaping as a
percentage of the open lot area, and on-site tree planting.
If a development meets only the minimum standards for
recreational space, instead of the preferred standard, it
would have to meet the preferred level of compliance for the
size of the average dwelling unit, a component of the
Building Interior program.
Other Building Interior requirements include windows larger
than those required by the Building Code, laundry facilities
and trash storage.
The Safety and Security element includes minimum and
preferred standards for the number of apartments per
corridor. Other requirements include: building entrances
visible from the street, and elevators and stairs visible
from both the building entrance and individual apartments.
Other Zoning Districts
Certain historic parts of the city are designated with the
letters LH to indicate a limited height district. These
limited height districts ensure that the height of new
buildings is in scale with existing buildings in the area.
R10-H allows transient hotels, by special permit, in addition
to residential and community facility uses. This district is
mapped primarily on Central Park South in Manhattan.
Zoning Analysis of a Typical Building in an R4-1 District
A builder planning the construction of two semi-detached
houses owns two adjacent 25 by 100 foot interior zoning lots
in an R4-1 district. (This analysis and all calculations will
refer to a single building; both semi-detached houses will
share a common zoning lot line and be mirror images of each
other.) The maximum FAR for an R4-1 district is 0.75.
However, the total applicable FAR will be 0.90 because the
builder plans to utilize the attic allowance that permits an
additional 20 percent of the 0.75 base FAR. Therefore, the
floor area of the house could be 2,250 square feet (0.90
times 2,500). As permitted, in an R4-1 district, an
additional 100 square feet will be added to the total floor
area of the house because the required parking space will be
in a detached accessory garage reached by a driveway running
along the side lot line. The maximum total floor area of the
building is 2,350 square feet.
There is no maximum lot coverage in an R4-1 district; the
maximum building dimensions are determined by yard
requirements. The rear yard must be at least 30 feet deep to
provide adequate light, air and recreational space. The
minimum depth of a front yard in an R4-1 zone is ten feet. If
the front yards of the adjacent zoning lots are deeper than
ten feet, the front yard of the new building must be at least
as deep as one of the adjacent front yards in order to
preserve a consistent building line along the street. (The
front yard need not exceed 20 feet.) Since the shallower of
the two adjacent yards is 12 feet in depth, the builder will
utilize the minimum permitted front yard depth and provide a
front yard that is also 12 feet deep. The required side yard
for a semi-detached building in an R4-1 district is four
feet; eight feet is required between buildings on adjacent
zoning lots. The house on the adjacent zoning lot is a zero
lot line building that abuts the side lot line. Therefore,
the side yard of the new building must be a minimum of eight
feet wide. On a 25 by 100 foot lot, the building footprint
will be 986 square feet (58 times 17). There is no required
open space ratio but at least 33 percent of the remaining
open space on the zoning lot must be open and not used for
driveways or open parking. The minimum width of the side yard
driveway is eight feet. The garage at the rear end of the
driveway will be 10 feet by 20 feet. Therefore, the square
footage of the driveway is 640 square feet (8 times 80). When
that is deducted from the 1,514 square feet of open space on
the lot, the combined front and rear yards (inclusive of the
garage) total 714 square feet which is 60 percent of the
remaining open space on the zoning lot.
To be compatible with adjacent houses, the perimeter wall may
be no higher than 25 feet. Above that, the building may reach
a maximum height of 35 feet at the ridgeline of a peaked roof
within the parameters of the building envelope.
Density in an R4-1 zone is controlled by a requirement that
there be at least 970 square feet of lot area for each
dwelling unit A 2,500 square foot lot permits a two-family
house. A two-family, semi-detached house has minimum floor
area requirements for each dwelling unit one must have a
minimum of 925 square feet; the other must be at least 300
square feet. At least 75 percent of the floor area of one
dwelling unit must be directly above or below the other
dwelling unit In this case, the floor area of a first floor
dwelling unit would be 986 square feet. In an R4-1 district,
when the block is characterized by buildings with second
story setbacks, the second story of the new dwelling must be
set back to duplicate the configuration of the other houses
on the street. Since the second story setback of the adjacent
buildings is ten feet, the floor area of the second floor
dwelling unit would be 816 square feet (48 times 17). The
floor area of the second floor dwelling unit may be increased
by adding floor area on the third floor, creating a duplex
unit The amount of floor area on the third floor is
determined by the dimensions of the building envelope but
could be no more than 548 square feet. No more than two
dwelling units are permitted in a house in an R4-1 district
The required parking ratio in an R4-1 district is one space
for each dwelling unit. In this example, parking would be
located within the garage on the rear lot line that is
entered through the side yard driveway and on the driveway
itself. This traditional pattern of many older neighborhoods
alleviates the parking problems created by continuous curb
cuts. The curb cut may be no more than ten feet wide and must
be an extension of the side lot ribbon. There must be a
minimum of 16 feet between curb cuts on adjacent zoning lots.
The resulting building, a two and one-half story, semi-
detached house with a pitched roof on a 2,500 square foot
lot, would cover almost 40 percent of the zoning lot and
contain 2,350 square feet of floor area. It would have two
dwelling units. At least one of the dwelling units would be
on two floors. On-site parking would be provided for both
dwelling units in the garage and within the side yard
driveway.
In zoning terminology the building would be described in the
following manner:
| Lot area: | 2,500 square feet |
| Maximum permitted floor area ratio: | 0.75 |
| Attic allowance: | 0.15 |
| Total permitted floor area ratio: | .90 |
| Accessory garage floor area bonus: | 100 square feet |
| Resulting Floor Area: | 2,350 square feet |
| Minimum required rear yard: | 30 feet |
| Minimum required front yard: | 10 feet (12 feet provided) |
| Minimum required side yard: | 4 feet or 8 feet from adjacent building (8 feet provided) |
| Number of dwelling units permitted: | 2 |
| Required number of parking spaces: | 2 |
| Use: | Use Group 2 (Use Group 2 comprises any type of
residential development designed for permanent occupancy
other than single-family detached residences)
|
Zoning Analysis of a Typical Building in an R6 District
A developer planning the construction of a six-story building
owns a lot 200 by 100 feet in an R6 district. The maximum FAR
for a six-story building in an R6 district is 2.14.
Therefore, the building could have a maximum floor area of
42,800 square feet (2.14 times 20,000).
The floor area of a building is the sum of the gross area of
all floors, excluding cellars (where more than half of the
story is below curb level), and space used for mechanical
equipment. Space used for an accessory garage located within
the structure, but which is no higher than 23 feet above curb
level, is also excluded from floor area calculations.
The amount of open space on the zoning lot can be computed
when the floor area of the building is known. With an open
space ratio of 30, an area equal to 30 percent of the total
floor area of the building must be provided on the lot as
open space. Open space, as defined in the Zoning Resolution,
is that part of a zoning lot which must be open and
unobstructed to the sky. It must be accessible to all
residents of a building. (Under certain circumstances, roof
area counts as open space and in certain districts need not
be accessible to occupants.) Certain obstructions, such as
unenclosed terraces and swimming pools, are permitted in open
space and up to 50 percent of the required open space may be
used for off-street parking. The required open space for this
building would be approximately 12,840 square feet or 30
percent of 42,800, the allowed floor area. Approximately 64
percent of the lot would be open space.
In this example, the building must provide a 30-foot rear
yard to ensure that adequate amounts of light and air reach
the rear of the building and the adjoining property. No side
yards or front yards are required in this district. However,
the open space regulations are flexible and generous yards
could be provided in front of or along the sides of the
building, or the structure could be built at the front lot
line with most of the open space at the rear.
The number of rooms allowed in the building is determined by
the amount of lot area required for each room. A minimum lot
area per room of 105 square feet is required in an R6
district for a building with the open space ratio of 30.
Therefore, a building erected on this 20,000-square-foot lot
would be allowed 190 rooms.
These 190 rooms could be used for approximately 50 dwelling
units of various sizes (from one to three or more bedrooms).
For zoning purposes, a studio apartment counts as 2-l/2
rooms, a one-bedroom apartment counts as 3-1/2 rooms, and a
two-bedroom apartment counts as 4-1/2 rooms.
The parking requirement for this building is 70 percent of
the number of dwelling units. Therefore, 35 parking spaces
are required. About 18 parking spaces could be provided in
the form of open parking on the zoning lot within the 50
percent of open space that may be devoted to parking. The
remaining 17 parking spaces would have to be provided in a
garage in the basement of the building.
The resulting building, a six-story structure on a 20,000-
square-foot lot, would cover nearly 36 percent of the lot and
would contain 42,800 square feet in floor space. It would
have 50 apartments (a likely breakdown would be 20 two-
bedroom units, 25 one-bedroom units and five studio
apartments) with 35 parking spaces.
In zoning terminology the building would be described in the
following manner
| Lot area: | 20,000 square feet |
| Maximum permitted floor area ratio: | 2.14 |
| Resulting Floor Area: | 42,800 square feet |
| Required Open Space Ratio: | 30 feet |
| Required Open Space: | 12,840 square feet |
| Required rear yard: | 30 feet |
| Required front yard: | None |
| Required side yard: | None |
| Number of rooms permitted: | 190 |
| Number of dwelling units: | 50 |
| Required number of parking spaces: | 35 |
| Use: | Use Group 2 (Use Group 2 comprises any type of
residential development designed for permanent occupancy
other than single-family detached residences)
|
Zoning Analysis of a Typical Building in an R6A District
A developer planning to construct a six-story residential
building owns a 200 by 100 foot interior lot on a wide street
in an R6A district. The maximum FAR in the district is 3.0.
Therefore, the building could have a maximum floor area of
60,000 square feet (3.0 times 20,000).
In an R6A district the front sky exposure plane begins 60
feet above the level of the street line and rises at a 1 to 1
ratio. The rear sky exposure plane, which also rises at a 1
to 1 ratio, begins 20 feet above the level of a line 100 feet
back from the street. Thus, a building may rise to 60 feet at
the front line. In the rear, a 60-foot-deep building may rise
60 feet without a setback. These height and setback
requirements would permit construction of the desired six-
story building.
In an R6A district the required minimum lot area per dwelling
unit is 227 feet. Therefore, the building may have a maximum
of 88 apartments (20,000 divided by 227). However, because
the developer must use the Quality Housing Program in an R6A
district, the maximum number of apartments in this building
may be affected by two other factors: the average dwelling
unit size must be at least 575 net square feet, in which case
the developer must provide the preferred standard of
recreation space (see below), or the developer may choose to
provide the preferred average dwelling unit size of 750 net
square feet, in which case the developer may comply with the
minimum standard of recreation space.
In this example, the developer seeks to maximize the number
of dwelling units, but the marketing strategy dictates that
20 percent of the units will be studios with 450 net square
feet, 50 percent one-bedroom units with 625 net square feet,
and 30 percent two-bedroom units with 825 net square feet.
Although the developer will not provide 750 square feet per
apartment, he will provide more than the minimum required,
575 square feet. The net square feet of a dwelling unit is
comprised of all the floor area within the perimeter walls of
the apartment. Therefore, all mechanical equipment spaces,
the apartment's perimeter walls, recreation and laundry
rooms, stairs, elevators, corridors and lobbies, are not
counted toward the net floor area of an apartment. In
general, only about 85 percent of the gross floor area of a
building is inside the apartments. In this illustration,
about 51,000 square feet will be available for the apartments
(60,000 x .85). Given the apartment distribution and size
noted above, the building will have 78 dwelling units,
averaging 648 net square feet. The total net residential
floor area will be 50,550 square feet.
The rest of the Quality Housing Program requirements
(excluding the planting area) will be calculated on the basis
of 78 dwelling units and a total net residential floor area
of 50,550 square feet. These requirements include:
- Trash collection and storage area in cellar:
- 2.9 cubic feet per DU x 78 = 226 cubic feet required
- Recycling and trash disposal room on each floor:
- 12 square feet required
- Total area required: 72 square feet*
- *Discounted from floor area calculations.
- Laundry room(s):
- Required machines:
- 1 washer per 20 DUs = 4 machines
- 1 dryer per 40 DUs = 2 machines
- Total = 6 machines required for 78 DUs
- Minimum size laundry room required:
- 6 machines x 7.5 sq. ft. per machine = 45 square feet
- 45 sq. ft. x 3 = 135 square feet
- Total area required = 180 square feet*
- * Discounted from floor an a calculations.
- Recreation space: Preferred standard
- Child use (indoor or outdoor)
- 2% x 50,550 = 1,011 square feet
- Joint use (indoor)
- 1% x 50,550 = 506 square feet
- Joint use (outdoor)
- 3% x 50,550 = 1,517 square feet
- Total indoor* = 506 square feet provided
- Total outdoor = 2,528 square feet (1,011 + 1,517) provided
- Required parking:
- 50 percent of 78 dwelling units or 39 spaces
- The 39 parking spaces will require 15,600 square
- feet (400 square feet of space per vehicle).** This
- space will be provided by excavating most of the
- site and placing the cars in the cellar of the
- building and below a portion of the rear yard.
** Estimated gross floor area of a self-park space in a
cellar garage.
The required planting area will be located in front of the
building if the building is set back from the street, and in
the rear yard above the below-grade garage. Up to 30 percent
of the required planting area may be developed as outdoor
recreation space; in this case it will be located above the
below-grade garage at the rear of the building. The Quality
Housing Program requires developers to plant one tree for
every 2,000 square feet of lot area in R6A districts,
yielding 10 on-site trees in this development. In addition,
one street tree must be planted in the sidewalk for every 25
feet of lot frontage, resulting in eight trees along the
street.
In zoning terminology the building would be described in the
following manner:
| Lot area: | 20,000 square feet |
| Maximum permitted floor area ratio: | 3.0 |
| Maximum permitted lot coverage: | 65% (50.6% actually covered) |
| Required rear yard: | 30 feet (35 feet provided) |
| Required front yard: | None (5 feet provided) |
| Required side yard: | None (31 feet provided) |
| Lot area per dwelling unit: | 227 square feet |
| Number of dwelling units: | 88 (78 provided) |
| Required number of parking spaces: | 39 |
| Required outdoor recreation area: | 2,528 square feet |
| Required planting area: | Required planting area front setback area plus 50% of area in
side and rear yards
|
