Chapter 4 - Special Regulations Applying in Flood Hazard Areas
The provisions of this Chapter establish special regulations which are designed to encourage flood-resilient building practices for new and existing buildings and in so doing to promote and protect public health, safety and general welfare. These general goals include, among others, the following purposes:
(a) to facilitate the development and alteration of buildings in flood zones consistent with the latest flood-resistant construction standards of the Federal government and the New York City Building Code;
(b) to enable buildings to be constructed pursuant to flood-resistant standards with a comparable amount of usable interior space to what is generally permitted within the applicable zoning district;
(c) to mitigate the effects of elevated and flood-proofed buildings on the streetscape and pedestrian activity;
(d) to expedite the recovery of neighborhoods that experienced a high concentration of damage to single- and two-family residences from Hurricane Sandy within the Neighborhood Recovery Areas specified in Appendix A of this Chapter; and
(e) to promote the most desirable use of land and thus conserve and enhance the value of land and buildings, and thereby protect the City's tax revenues.
The provisions of this Chapter shall be in effect until one year after the adoption by the City of New York of new final Flood Insurance Rate Maps superseding the Flood Insurance Rate Maps in effect on October 28, 2012.
Definitions specifically applicable to this Chapter are set forth in this Section and may modify definitions set forth in Section 12-10 (DEFINITIONS). Where matter in italics is defined both in Section 12-10 and in this Chapter, the definitions in this Chapter shall govern.
For buildings, or portions thereof, that comply with flood-resistant construction standards, a "basement" is a story (or portion of a story) partly below flood-resistant construction elevation, with at least one-half of its height (measured from floor to ceiling) above flood-resistant construction elevation.
For buildings, or portions thereof, that comply with flood-resistant construction standards, a "cellar" is a space wholly or partly below the flood-resistant construction elevation, with more than one-half its height (measured from floor to ceiling) below the flood-resistant construction elevation.
Flood-resistant construction elevation
The "flood-resistant construction elevation" is the greater of:
(a) the "design flood elevation" determined pursuant to Appendix G of the New York City Building Code for a building's structural occupancy category; or
(b) the base flood elevation indicated on the flood maps, plus the additional elevation required above base flood elevation for the applicable occupancy category when determining the Design Flood Elevation pursuant to Appendix G of the Building Code.
Flood-resistant construction standards
"Flood-resistant construction standards" shall:
(a) comply with the standards of Appendix G of the Building Code for "Post-FIRM Construction," whether construction voluntarily complies with standards for "Post-FIRM Construction" or is required to comply; and
(b) utilize the higher base flood elevation and the more stringent flood hazard area designation, as applicable, of the flood maps or the Flood Insurance Rate Maps in effect on October 28, 2012.
"Hurricane Sandy" is a severe storm that occurred on October 28, 2012, causing heavy flooding, power outages, property damage and disruption of public transportation and other vital services.
Lowest occupiable floor
The "lowest occupiable floor" shall be the finished floor level of the lowest floor that is not used solely for parking, storage, building access or crawl space, where any space below such lowest occupiable floor is wet flood-proofed in accordance with flood-resistant construction standards and used only for parking, storage or building access, or otherwise is not occupiable space.
Predominant or predominantly
"Predominant" or "predominantly" shall mean that a use or a group of uses comprises at least 75 percent of the total floor area of the building or of the area of the zoning lot, as applicable.
The provisions of this Chapter shall apply only within the flood zone, as follows:
(a) Except where otherwise stated, all buildings, or portions thereof, shall comply with flood-resistant construction standards as a condition of construction pursuant to the following optional provisions, as applicable, inclusive:
Section 64-10 GENERAL PROVISIONS
Section 64-20 SPECIAL USE REGULATIONS
Section 64-30 SPECIAL BULK REGULATIONS
Section 64-40 SPECIAL BULK REGULATIONS FOR BUILDINGS EXISTING ON OCTOBER 28, 2012
Section 64-50 SPECIAL PARKING REGULATIONS
Section 64-70 SPECIAL REGULATIONS FOR NON-CONFORMING USES AND NON-COMPLYING BUILDINGS
Section 64-80 MODIFICATION OF SPECIAL REGULATIONS APPLYING IN WATERFRONT AREAS
Section 64-90 SPECIAL APPROVALS
(b) The provisions of Section 64-60 (DESIGN REQUIREMENTS) shall apply to all developments, all horizontal enlargements with new street walls, or alterations that increase the height of street walls, except that Section 64-65 (Screening Requirements for Parking Within or Below Buildings) shall apply to all buildings as provided therein.
(c) Where a zoning lot is located partially within a flood zone, the regulations of this Chapter shall apply where any portion of a building on such zoning lot is within such flood zone.
(d) In Neighborhood Recovery Areas, shown on maps in Section 64-A80 (NEIGHBORHOOD RECOVERY AREA MAPS) of this Chapter, optional provisions to expedite the vertical elevation or reconstruction of single- or two-family residences shall apply. These provisions are set forth in Appendix A and shall supplement, supersede or modify the provisions of this Chapter. The maps are hereby incorporated and made part of this Resolution, for the purpose of specifying locations where special regulations and requirements set forth in the text of this Chapter may apply.
The regulations of all other chapters of this Resolution are applicable, except as superseded, supplemented or modified by the provisions of this Chapter. In the event of a conflict between the provisions of this Chapter and other regulations of this Resolution, the provisions of this Chapter shall control.
All measurements of height above curb level, base plane, base flood elevation, grade or other similar ground related datum, shall be from the flood-resistant construction elevation. This provision shall not apply to buildings that are accessory to single- or two-family residences, or to fences, signs not affixed to buildings, or other structures that are not buildings.
In R3, R4-1 and R4A Districts within lower density growth management areas, the maximum perimeter wall height shall be 21 feet above the flood-resistant construction elevation or 26 feet above grade, whichever is greater.
Where different flood-resistant construction elevations apply to different portions of a building, the highest of such flood-resistant construction elevations may apply to the entire building.
For buildings located partially within and partially outside of the flood zone, all measurements of height shall be in accordance with only one of the following provisions:
(a) the flood-resistant construction elevation shall apply to the entire building;
(b) the height of the portion of the building within the flood zone shall be measured from the flood-resistant construction elevation, and the height of the portion of the building outside of the flood zone shall be measured from an elevation determined in accordance with the underlying applicable regulations; or
(c) the elevation of each such portion of the building from where height is measured shall be multiplied by the percentage of the total lot coverage of the building to which such elevation applies. The sum of the products thus obtained shall be the elevation from which the height of the entire #building is measured.
(a) In all districts, where compliance with the elevation and wet flood-proofing requirements of Appendix G of the New York City Building Code would result in a lowest occupiable floor that is above a level required by the Zoning Resolution without the relief provided by this Section, such requirements shall be modified so that the level of such ground floor shall be the lowest level permitted for uses other than parking, storage and building access as if it were "Post-FIRM Construction," as defined by Appendix G of the Building Code, using elevation and wet flood-proofing techniques.
(b) In C1, C2 and C4 Districts in the Borough of Staten Island, where flood-resistant construction elevation is more than 10 feet above curb level, the provisions of Section 32-433 (Ground floor use in C1, C2 and C4 Districts in the Borough of Staten Island) shall be modified to allow enclosed parking spaces, or parking spaces covered by a building, including such spaces accessory to residences, on the ground floor within 30 feet of the street wall of the building, provided that the standards of Section 64-641 (Transparency requirements) are met.
In all districts, as an alternative to street wall transparency regulations, the following optional provisions may apply, except where buildings are governed by the provisions of Section 64-64 (Design Requirements for Non-residential and Mixed Buildings in Commercial and Manufacturing Districts).
Street walls shall be glazed with transparent materials which may include show windows, transom windows or glazed portions of doors. Such transparent glazing materials shall occupy at least 50 percent of the surface area of such street wall, measured between the level of the first finished floor above curb level and a height 12 feet above such level.
For single- and two-family residences with enclosed entryways below flood-resistant construction elevation, up to 10 square feet of such entryway may be excluded from the definition of floor area for each foot of difference between the lowest occupiable floor and curb level. This area may be excluded from the definition of floor area provided it is not greater than the total area of ramps, stairs, lifts and elevators between grade and the first finished floor, plus an initial entry area of no more than 12 square feet.
For all buildings other than single- and two-family residences, with enclosed publicly accessible entryways below flood-resistant construction elevation, up to 100 square feet of such entryways may be excluded from the definition of floor area for each foot of difference between the lowest occupiable floor and curb level. This area may be excluded from the definition of floor area provided it is not greater than the total area at each publicly accessible entryway of ramps, stairs, lifts and elevators plus an initial entry area of no more than 100 square feet for each entryway.
Floor space used for accessory mechanical equipment in R1-2A, R2A, R2X, R3, R4 or R5 Districts may be excluded from the definition of floor area without the limitations provided in the definition of floor area, paragraphs (m) and (8) in Section 12-10 (DEFINITIONS).
The provisions of this Section shall apply without requiring a building to comply with flood-resistant construction standards as established in paragraph (a) of Section 64-12 (Applicability).
Underlying yard regulations shall be modified to allow yards to be higher than curb level but in no event higher than flood-resistant construction elevation. In addition, the following regulations shall apply:
(a) in Residence Districts and C1 through C6 Districts, yards higher than curb level shall comply with the following standards:
(1) final grade shall not penetrate a plane that begins 30 inches above curb level at each lot line and has a slope extending perpendicular to lot lines of one foot vertical for each 2.5 feet horizontal;
(2) retaining walls shall be permitted above curb level in yards provided the maximum height of each wall above adjacent grade does not exceed 30 inches; and
(3) in front yards in Residence Districts, portions of fences greater than four feet above curb level shall be required to be no more than 50 percent opaque; and
(b) in C7 and C8 Districts and in Manufacturing Districts, yards shall be permitted to a maximum grade equal to flood-resistant construction elevation. However, for portions of zoning lots where Sections 33-29 and 43-30 (SPECIAL PROVISIONS APPLYING ALONG DISTRICT BOUNDARIES) apply, yards are permitted above curb level only pursuant to paragraph (a) of this Section.
Nothing in this Section shall be construed so as to permit the creation of spaces sub-grade on all sides in a manner inconsistent with Appendix G of the Building Code.