NYC Zoning Handbook: Lower Density
Contextual Zoning: Technical Provisions
Chapter 9
Adopted in 1989, lower density contextual zoning seeks to restore a
meaningful difference between R3, R4 and R5 districts and ensure that
new residential development in low-rise neighborhoods is compatible with
existing housing. In order to achieve these goals, the zoning text
incorporated a number of modifications that alter the bulk, density,
configuration and parking requirements in lower density residential
districts.
Some requirements have become simpler. A maximum lot coverage
percentage instead of an open space ratio now determines how much of a
zoning lot may be covered by a building. Where no lot coverage
requirement is stated, coverage is regulated by yard requirements.
Density is now regulated by the minimum amount of lot area per dwelling
unit instead of the minimum amount of lot area per zoning room, a change
previously implemented in the medium and higher density contextual
districts.
Height and Setback
New height and setback rules which limit overall building height
maintain the existing streetscape and re-establish the distinctions
among residential districts. In zoning districts where peaked roofs and
setbacks predominate (R2X, R3A, R3-1, R3-2, R4, R4-1 and R4A), the new
regulations permit residential buildings with at least two full floors
or two floors and an attic. In R2X, R3 and R4A districts, the maximum
perimeter wall height of a building is 21 feet; in R4 and R4-1
districts, 25 feet. A third floor is permitted within the parameters of
the designated building envelope. The envelope has a series of planes
which permit a variety of pitched roof and setback designs that reflect
neighborhood scale. The maximum height at the apex of the envelope is 35
feet.
Zoning districts characterized by rowhouses and small apartment
buildings also have new height and setback regulations. In R4B
districts, a height limit of 24 feet permits rowhouses of at least two
full floors. In RS and R5B districts, rowhouses and apartment buildings
may have a maximum street wall height of 30 feet. Above this height,
buildings with setbacks may reach a total height of 33 feet in R5B
districts and 40 feet in R5 districts.
Floor Area
Rules for determining what may be counted in floor area calculations
have changed to more accurately reflect the actual amount of usable
living space. Attic space is no longer excluded from total floor area;
the new attic allowance permits additional floor area under certain
conditions. In neighborhoods where buildings with pitched roofs
predominate (R2X, R3, R4, R4A and R4-1), the attic allowance grants
additional FAR of up to 20 percent of the base FAR for space with
ceiling heights of between five and eight feet located beneath a pitched
roof, whether on the top floor or on a lower floor.
The exclusion of enclosed parking space from the floor area count has
been eliminated in some building configurations and districts and
limited in others. Garages in detached and semi-detached residential
buildings count in full as floor area. Garages in attached residential
buildings, however, receive a deduction of up to 100 square feet from
the floor area count. Freestanding garages are not included as floor
area nor are garages with five or more spaces whose ceiling height is
not more than six feet above grade. For detached and semi-detached
buildings in R3-2, R4 and R5 districts, an additional 100 square feet of
floor area may be added to the base floor area to encourage the
provision of a separate accessory garage in the rear yard. All floor
space in cellars continues to be excluded from the floor area count.
Front Yards
Minimum front yard depths are required in order to maintain the common
streetscape and the relationship of residential buildings in specific
districts. The minimum front yard depth is 10 feet in R3A, R4-1 and R4A
districts; if each of the adjacent front yards is deeper than 10 feet,
the front yard of a new building must be at least as deep as one of the
adjacent yards although it need not exceed 20 feet. For example, if the
adjacent yards are 12 feet and 15 feet deep, the depth of the front yard
must be at least 12 feet.
The minimum front yard depth is five feet in R4B and R5B districts; if
each of the adjacent front yards is greater than five feet, the front
yard of a new building must be at least as deep as one of the adjacent
yards but no deeper than the other adjacent front yard although it need
not exceed 20 feet. For example, if the adjacent front yards are six
feet and eight feet deep, the depth of the front yard must range between
six and eight feet. In R4 and R5 districts without a suffix, front yards
must be either 10 feet in depth to forestall front yard parking, or a
minimum of 18 feet to ensure that cars parked in front yard driveways do
not jut onto the sidewalk. Front yard depths between 10 feet and 18 feet
are not permitted.
Front yard requirements pertain to enlargements and additions to
existing buildings as well as new construction.
Parking
New parking regulations that restrict curb cuts and driveway locations
will increase the availability of curbside parking and promote the
landscaping of front yards. For single- and two-family houses on narrow
zoning lots (less than 35 feet in width), parking must be provided in a
side lot ribbon which is a driveway that runs parallel to the side lot
line. A minimum of 16 feet is required between curb cuts to expand the
number of curbside parking spaces. Single- and two-family houses on
wider lots must provide at least 18 feet of curbside parking space.
Rowhouse developments may have curb cuts no wider than 15 feet serving
paired driveways and must maintain 16 feet of curbside parking space.
Side lot ribbons, which are prevalent in many older neighborhoods,
eliminate uninterrupted curb cuts that disrupt curbside parking. Side
lot ribbons also foster planted front yards in lower density communities
by eliminating front yard paved parking.