A STRONGER, MORE RESILIENT NEW YORK71 A STRONGER, MORE RESILIENT NEW YORK increasingly high safety standards. While this approach has improved building safety over time, the corollary

A STRONGER, MORE RESILIENT NEW YORK

Credit: Barry Yanowitz

CHAPTER 4 | BUILDINGS 68

Buildings

A STRONGER, MORE RESILIENT NEW YORK69

1983 FIRMs 100-Year FloodplainSandy Inundation Area

Comparison of 100-Year Floodplain in 1983 FIRMs and Sandy Inundation Area

Bungalows in New Dorp Beach. Rowhousesin Sheepshead Bay. Office towers in LowerManhattan. Industrial warehouses alongthe waterfront in Sunset Park. New York Cityhas a diverse building stock encompassing approximately 1 million structures of almostevery imaginable type and combination of uses.These buildings are New York City’s homes, workplaces, museums, historic landmarks, commu-nity centers, and places of worship—and theyare also critical contributors to the rich and varied character of communities across the city.

However, because New York is a coastal city, itsbuildings have long been subject to climaterisks, particularly the flooding associated withstorm surge and sea level rise. In fact, when theFederal Emergency Management Agency(FEMA) released its first Flood Insurance RateMaps (FIRMs) for New York City in 1983, it defined the 100-year floodplain—the area thathas a 1 percent or greater chance of flooding inany given year—as an expanse that today includes approximately 35,500 buildings withmore than 376 million square feet of space.While these maps demonstrated the city’s long-standing vulnerability to flooding, Sandyshowed that New York’s buildings are evenmore vulnerable than previously thought.Sandy’s floodwaters inundated an area that

included approximately 88,700 buildings, morethan half of which were located outside the1983 floodplain boundaries that were in effectwhen the storm arrived. These buildings encompassed roughly 662 million square feetof space and housed more than 443,000 resi-dents and 245,000 jobs. (See map: Comparisonof 100-Year Floodplain in 1983 FIRMs andSandy Inundation Area)

Sandy’s impact is illustrative of the city’s grow-ing climate risks. For example, the 100-yearfloodplain, defined on recent Preliminary WorkMaps (PWMs) created by FEMA, now encom-passes more than 67,700 buildings, nearlytwice the number of buildings in the 1983FIRMs. In addition to the risks that the PWMs in-dicate these buildings now face, many of theseproperties also will be subject to significantnew Federal flood insurance requirements.

However, even the revised FEMA flood maps donot reflect the full risk to New York City’s build-ing stock. That is because these maps arebased on historical storm profiles and do nottake into account potential changes in coastalstorms or projected sea level rise, which, basedon recent high end projections for sea level rise,could expand the size of the city’s floodplain toinclude more than 88,000 buildings by the

2020s and more than 114,000 buildings by the2050s (see Chapter 2, Climate Analysis). Theyalso do not take into account other risks thatclimate change could exacerbate, includingstorm-related wind gusts.

Coastal protection measures are a significantand critical part of the City’s efforts to protectbuildings from current and future climate risks(see Chapter 3, Coastal Protection). While thesemeasures should reduce the effects of stormsurge, destructive waves, and sea level rise, theywill not eliminate completely those impactsunder all potential storm conditions, and theyalso will take time to design, fund, and build.Thus, they address only part of the challenge fac-ing New York City’s building stock. It is thereforeequally important to supplement coastal protection measures by pursuing resiliency atthe building level, offering multiple approachesto protect a wide range of the city’s structuresagainst the full spectrum of climate risks.

That is why this chapter proposes a two-partstrategy for the city’s building stock that is inkeeping with the overarching goals of this report—to reduce the impacts of climatechange, while also enabling the city to bounceback quickly when such impacts are felt. Thetwo-part strategy seeks to strengthen new

Source: FEMA MOTF 11/6 Hindcast surge extent


and rebuilt structures to meet the highest avail-able standards and to facilitate the retrofittingof as many existing buildings as possible so thatthey become significantly more resilient thanthey are today. This approach will benefit a fullrange of buildings—those that are and may become vulnerable; those that are new and preexisting; those that are residential and non-residential; those that were impacted bySandy and those that were not.

How the Building System Works

Any understanding of the vulnerabilities of New York’s buildings must start with an under-standing of the types of structures in the cityand how they are regulated.

Structural Characteristics and Uses of NewYork City’s Building Stock New York City’s buildings can be categorized bythe following attributes, all of which are relevantfor resiliency: • physical characteristics; • building use; and• building age.(See photos: Common Building Types AcrossNew York City)

New York’s buildings can be categorized bybuilding height, construction type (as definedby the Building Code), and proximity to otherstructures. Building height ranges from low-rise(1 or 2 floors) to mid-rise (3 to 6 floors) to high-rise (7 floors and up). Meanwhile, there aretwo main construction types: so-called “com-bustible” buildings that are built using lighterstud-frame construction or wood joists on ma-sonry bearing walls; and “non-combustible”buildings that use steel or masonry and concrete frames. Buildings in New York also canbe characterized by their proximity to eachother: they can be detached (freestanding);semi-attached (sharing a wall with anotherbuilding); or attached (sharing walls on at leasttwo sides with adjoining buildings). (See table:Categorization of New York City Buildings byPhysical Characteristics)

Finally, buildings in New York also can be categorized by their age. This is a key factor because it correlates to the rules applicable atthe time of the building’s construction—andtherefore the type of construction used.

Ever since Peter Stuyvesant instituted the firstbuilding regulations in New York in 1648 (ap-pointing fire wardens to inspect buildings for firehazards), the City’s regulations governing theconstruction and the location of buildings haveevolved, ensuring that new buildings meet

Common Building Types Across New York City

Attached 1- and 2-Family HomeDetached 1- and 2-Family Home

Low- to Mid-Rise Mixed-Use Building

High-Rise Commercial Building High-Rise Multi-Family Building

Low- to Mid-Rise Commercial Building

Building Height• Low-rise: 1 or 2 floors• Mid-rise: 3 to 6 floors• High-rise: 7 floors and up

Construction Type(as defined by the Building Code)

• “Combustible” buildings: built using lighter, stud-frameconstruction; or wood joists on masonry bearing walls

• “Non-combustible” buildings: built using steel, or masonry and concrete frames

Proximity• Detached: freestanding• Semi-attached: sharing a wall with another building• Attached: sharing walls on both sides with adjoining buildings

Categorization of New York City Buildings by Physical Characteristics

Credit: Alexandros Washburn

Credit: John Hans Lee Credit: DOB/Samantha Modell

Credit: Wikimedia/Beyond My Ken

Credit: DCP

Credit: Wikimedia/Jim HendersonCredit: DOB/Samantha Modell

Low- to Mid-Rise Industrial Building


increasingly high safety standards. While thisapproach has improved building safety overtime, the corollary of this is that many olderstructures in the city were built according to codes that leave them more vulnerable to extreme weather events than buildings con-structed to more modern standards.

Regulatory Framework for New YorkCity’s Building Stock Buildings in New York City are governed by awide variety of rules and regulations. Two Cityagencies share primary responsibility for over-seeing New York’s buildings: the Department ofBuildings (DOB) and the Department of CityPlanning (DCP).

DOB regulates construction standards to ensure safe and lawful building use. DOB ac-complishes its mission by enforcing severalcodes and regulations, including the City’s Con-struction Codes (of which the Building Code isa part), the Electrical Code, and the Zoning Res-olution. DOB also is responsible for enforcingthe New York State Multiple Dwelling Law,which governs the habitability of multi-familybuildings in New York City.

DCP, meanwhile, establishes citywide regula-tions for building use, density, and bulk throughthe Zoning Resolution. DCP also initiates plan-ning and zoning changes for individual neigh-borhoods and business districts to promote theorderly growth and development of the city.Any changes to the Zoning Resolution initiatedby DCP require the approval of the City PlanningCommission and the City Council.

In addition to DOB and DCP, many other Cityagencies play critical roles in overseeing NewYork’s building stock. These include the Fire De-partment of New York (FDNY), the Departmentof Housing Preservation and Development(HPD), and the Board of Standards and Appeals(BSA). (See table: City Agencies That RegulateNew York’s Building Stock)

Thanks to the efforts of these agencies and oth-ers, New York has a long history of working toimprove the resiliency of its buildings. For example, the building codes and land use lawsenacted in the 1960s (including a new ZoningResolution passed in 1961 as well as criticalbuilding code revisions that culminated in anew Building Code in 1968) contained manymeasures that, while not explicitly designed toprotect buildings from climate risks, did seek to make buildings generally safer, and thus alsohad the effect of improving flood protection.

As larger buildings continued to be constructedto accommodate the city’s growing population,the City amended its Building Code to increase

fire protection requirements in areas with highconcentrations of residents. This resulted inheavier buildings that were constructed of non-combustible materials such as steel, concrete, and masonry—materials that also re-duced vulnerability to structural damage duringstorm surge and flooding events. Over time,older, light-frame buildings in central portionsof the city tended to be replaced by bigger,heavier buildings, while light-frame, low-densitybuildings remained more common on theedges of the city.

The City began actively and deliberately incor-porating resiliency into its building regulationsin 1983, when FEMA first released its FIRMs forNew York City, which set the boundaries of the100-year floodplain (see Chapter 2). In theFIRMs, the 100-year floodplain itself is dividedinto subzones that further delineate the level ofrisk, including V Zones, in which the physical impact of waves during flooding is expected tobe greatest, and A Zones, where waves are expected to be less significant. These mapsalso show the associated Base Flood Elevations(BFEs), or the height to which floodwaters potentially could rise.

These maps are relevant to New York’s buildingregulations because of the role they play in theNational Flood Insurance Program (NFIP), whichallows property owners to purchase flood insurance from the Federal government. First,properties in the 100-year floodplain are required to carry flood insurance, usually fromthe NFIP, if they are encumbered by Federallybacked mortgages (see Chapter 5, Insurance).Additionally, under Federal law, if jurisdictionssuch as New York want their citizens to be ableto purchase insurance from the NFIP, thenthese jurisdictions must incorporate nationallyrecognized flood-resistant construction stan-dards into their own building codes. Generally,these standards apply to new and substantiallyimproved buildings (i.e., buildings for which the cost of alteration is greater than 50 percentof their value, prior to improvement) in the floodplain. The City adopted these standards in 1983.

In addition to adhering to requirements established by the NFIP, New York City also isrequired to comply with a State regulation thatmandates that New York City’s local buildingcodes be at least as protective as the State’sown Building Code. This is relevant because, in

Agency Regulatory Role Applicable Regulations

Department ofBuildings (DOB)

• Regulates construction standards to ensure safe and lawful building use

• Construction Codes (of which the Building Code is a part)

• Electrical Code• Zoning Resolution• New York State Multiple

Dwelling Law

Department ofCity Planning(DCP)

• Regulates building uses, density, and bulk through the Zoning Resolution

• Initiates planning and zoningchanges for individual neighbor-hoods, as well as citywidechanges, subject to the approvalof the City Planning Commissionand the City Council

• Zoning Resolution

Fire Depart-ment of NewYork (FDNY)

• Regulates the maintenance andsafe use of buildings with regardto fire hazards

• Fire Code

Department of HousingPreservation and Develop-ment (HPD)

• Maintains and administers basicstandards for the safety and habitability of housing

• Housing Maintenance Code

Board of Standards andAppeals (BSA)

• Adjudicates appeals ofinterpretations of the Zoning Resolution, as well as variances and certain special permits

• Zoning Resolution

City Agencies That Regulate New York’s Building Stock


2010, New York State adopted an even higherelevation standard than was required under theNFIP, mandating that new and substantially improved buildings in the 100-year floodplainmust include “freeboard”—an incremental elevation above the BFE to which a buildingmust be flood-protected. Freeboard is one wayto compensate for uncertainties relating toflood modeling and to future sea level rise. Pursuant to this State requirement, 1- and 2-family homes were required to add 2 feet offreeboard to the BFE, while most non-residentialbuildings were required to add one foot offreeboard. The applicable elevation, BFE plusfreeboard, is referred to as the Design Flood Elevation (DFE). New York City adopted theState’s standard as part of an Emergency Ruleissued by DOB in January 2013. (See graphic:Flood Protection Terms)

In New York City, these Federal, State, and localstandards are incorporated into Appendix G ofthe Building Code, which outlines the flood-resistant construction techniques that are re-quired for new and substantially improved buildings in the 100-year floodplain. AppendixG is therefore a critical tool for protecting vulnerable buildings. (See chart: Overview ofAppendix G: Flood-Resistant Construction)

Pursuant to Appendix G and consistent with thestandards above, in residential buildings any-where in the 100-year floodplain, living areas arenot permitted below the DFE. Only parking,building access, and storage are permittedbelow such elevations. For residential buildingsin A Zones, any area below the DFE must be“wet flood-proofed,” a technique designed toallow floodwaters to enter and leave a structurethrough flood openings or vents. This approachallows hydrostatic forces—the pressure exertedby the sheer weight of water—to equalize onboth sides of building walls and thus preventsstructures from collapsing. Residential buildingsin A Zones also may comply with Appendix G byelevating their lowest floor above the DFE. (Seegraphic: Wet Flood-Proofing Method)

For a residential building in a V Zone, the entirestructure must be elevated on piles to preventthe lateral force of waves from damaging thestructure. In addition, areas below the DFE arerequired to be open or built with “breakaway”walls, such as non-supporting open-lattice walls,that can give way under water pressure withoutcausing the building to collapse.

Requirements for commercial buildings differfrom those of residential buildings. In A Zones,commercial buildings must have their lowestfloor elevated above the DFE or be “dry flood-proofed” (made watertight) below the DFE. Dryflood-proofing techniques are designed to prevent water from entering a structure (using,

WITHOUT

WITH

WET FLOODPROOFINGWet Flood-Proofing Method

Without wet flood-proofing, pressure from floodwaters builds up on one side of a building’s walls,often causing structural damage. With wet flood-proofing, openings or vents permit floodwatersto enter an enclosed area, allowing this pressure to equalize on both sides of the building’s walls thereby preventing the structural damage.

}}

DESIGN FLOOD ELEVATION (DFE)

BASE FLOOD ELEVATION (BFE)

FREEBOARD

FLOOD ELEVATION TERMSFlood Protection Terms

VERTICALFOUNDATION MEMBER

OPEN LATTICE BREAKAWAY WALL

LOWEST OCCUPIED FLOORALLOWED TO BE EXCAVATED BELOW GRADE

GROUND FLOORCONFIGURATION

PERMITTED USEBELOW DFE

FLOOD PROTECTIONSTRATEGY

DFEDFE DFE

NOT PERMITTED FOR ENTIRELY RESIDENTIAL BUILDINGS

NON-RESIDENTIALSPACE ONLY

V ZONEA ZONE

WET FLOOD-PROOFING

e.g., FLOOD VENTS

WATER TO RUN-IN / RUN-OUT

DRY FLOOD-PROOFING

e.g., FLOOD SHIELDS

WATERTIGHT STRUCTUREe.g., OPEN LATTICE BREAKAWAY WALLS

VIRTUALLY OPEN STRUCTURE

ELEVATED STRUCTURE

FLOOD SHIELDS PREVENT WATER FROM ENTERING

LOWEST OCCUPIED FLOORTO BE AT OR ABOVE DESIGN FLOOD ELEVATION

BOTTOM OF LOWESTSTRUCTURAL MEMBER

TO BE AT OR ABOVE DESIGN FLOOD ELEVATION

PARKING

ACCESS

STORAGE

NON-RESIDENTIAL

RESIDENTIAL

PARKING

ACCESS

STORAGE

NON-RESIDENTIAL

RESIDENTIAL

PARKING

ACCESS

STORAGE

NON-RESIDENTIAL

RESIDENTIAL

Overview of Appendix G: Flood-Resistant Construc tion

Source: DCP

73

for example, sealants, flood shields, or aquar-ium glass) and to strengthen structural components to resist hydrostatic forces fromfloodwaters. In V Zones, such dry flood-proofingof commercial uses is not permitted. Instead,as with residential buildings, the lowest occupied floor must be elevated above the DFE.(See graphic: Dry Flood-Proofing Method UsingTemporary Flood Shields)

For all new and substantially improved build-ings, Appendix G further requires that, regard-less of intended use, flood damage-resistantmaterials must be used below the DFE. Suchmaterials must be capable of withstanding di-rect and prolonged contact with floodwaters,without sustaining any damage that requiresmore than cosmetic repair. In addition, pur-suant to Appendix G, mechanical equipment(electrical, heating, ventilation, plumbing, andair conditioning systems) either must be located above the DFE or, if located below theDFE, must be protected so as to prevent it frombeing inundated with water.

Under Mayor Bloomberg, the City has beeneven more aggressive about building resiliency,focusing not just on surge and flood but also onother climate risks. For example, in 2008, theMayor and the City Council Speaker convenedthe Green Codes Task Force—an expert panelof architects, engineers, regulators, and otherstakeholders—to recommend changes to theCity’s codes and regulations to make buildingsmore sustainable. The group’s 111 recommen-dations included proposals to augment buildingstandards in the 100-year floodplain to accountfor rising sea levels and to ensure “passive sur-vivability”—providing residents with safe livingconditions in the event of citywide utility fail-ures. To date, 39 of the group’s recommenda-tions have been adopted by City agencies andthe City Council. Meanwhile, in 2011, DCP re-leased Vision 2020: New York City Comprehen-sive Waterfront Plan, a 10-year plan for the

city’s 520-mile waterfront that explicitly in-cluded increasing climate resiliency as one ofeight overarching goals, addressing in detail theneed to consider climate risks as a part of waterfront development.

In the immediate aftermath of Sandy, the City reexamined its existing flood-resistant construction rules so that rebuilding and newconstruction would reflect the best availabledata on coastal flood risk. As a result, on January 13, 2013, in collaboration with the CityCouncil, Mayor Bloomberg issued ExecutiveOrder 230, “An Emergency Order to SuspendZoning Provisions to Facilitate Reconstruction

in Accordance with Enhanced Flood ResistantConstruction Standards.” This emergencyorder suspended height and other zoning restrictions so that buildings could meet newadvisory flood elevation standards publishedby FEMA in February, without being penalizedunder the Zoning Resolution (for example, if elevation put a structure into conflict with zoning height limitations). This measure wasdesigned as a temporary tool so that buildingsbeing built or retrofitted post-Sandy would beconstructed safely, according to the then-bestavailable information.

In an effort to further promote resiliency, theMayor and the City Council Speaker convenedthe Building Resiliency Task Force (BRTF), an ex-pert panel of engineers, architects, developers,and property owners, along with representativesof City government. The BRTF, which workedclosely with those involved in developing this report, was charged with undertaking a comprehensive review of current code stan-dards and proposing changes with the goal ofensuring that, going forward, buildings would beconstructed to the most modern standards ofresiliency. Managed by the Urban Green Council,the local chapter of the US Green Building Coun-cil, the BRTF is developing proposals that will bereleased in 2013. These proposals will expandupon and complement the recommendationsoutlined in this chapter.

The effects of flooding and storm surge resulted in severe structural damage to many buildings during Sandy.

Dry Flood-Proofing Method Using Temporary Flood Shields

One method of dry flood-proofing is a temporary flood shield that can help prevent low-level floodingfrom entering through an openingsuch as a door or window.

Credit: DOB/Dan Eschanasy

Source: FEMA

A STRONGER, MORE RESILIENT NEW YORK

What Happened During Sandy

Building damage from storm surge and inundation during Sandy was widespread and inmany cases severe. Sandy flooded an area thatincluded approximately 88,700 buildings, or 9 percent of the city’s building stock. Thesebuildings encompassed 662 million square feetof space that included more than 300,000 housing units and 23,400 businesses. The stormcompletely destroyed or rendered structurallyunsound hundreds of buildings and damagedthousands more. More than 100 of these im-pacted homes and businesses were destroyedby storm-related fires, which were predomi-nantly electrical in nature and caused largely bythe interaction of electricity and seawater.

Following Sandy, both the Federal government(through FEMA) and City government (throughDOB) inspected the damage caused by thestorm. At the Federal level, as of February 15,2013, FEMA had completed inspections ofnearly 70,000 housing units that registeredwith FEMA for disaster assistance. These in-spections demonstrated that building damagevaried widely, both in terms of the dollar valueof losses and the level of flooding sustained.For example, of the approximately 47,000owner-occupied housing units inspected byFEMA, 49 percent had sustained damage in ex-cess of $10,000, with 12 percent sustainingdamage in excess of $30,000. Of the approxi-mately 22,000 rental housing units inspected,26 percent sustained “substantial damage”, thehighest damage classification used by FEMA,indicating that damage was 50 percent or moreof the pre-flood market value of the building.

The City’s building-level damage assessmentsfollowing Sandy were similarly comprehensive.These were led by DOB and represented thelargest building inspection initiative in New YorkCity history, teaming DOB inspectors and engineers with private-sector engineers whovolunteered to serve the effort in Rapid Assess-ment Teams. The result of this initiative was aseries of “tags” applied to buildings, rangingfrom “red” (indicating structural damage) to“yellow” (indicating that portions might be unsafe or might have significant non-structuraldamage) to “green” (indicating less seriousdamage or no damage at all).

The first set of these tags was issued by DOBRapid Assessment Teams that were sent to themost impacted sections of the city immediatelyfollowing Sandy (DOB Post-Storm Tags). Of theroughly 82,000 buildings receiving DOB Post-Storm Tags, approximately 73,000 of thebuildings were tagged as green (or 89 percentof the total), 7,800 were tagged as yellow (or

10 percent of the total), and 930 were taggedas red (or 1 percent of the total). Of the red-tagged buildings, 220 were further categorized as destroyed.

In December 2012, DOB conducted a follow-upassessment of the buildings that received DOBPost-Storm Tags, focusing on the roughly 8,700buildings that had earlier been tagged yellowor red (including those tagged as destroyed).This assessment sought to standardize DOB’sclassification methodology across the boroughs.Generally, this assessment took a more conser-vative approach, for example, assigning yellowtags for damage to building systems only inlarger buildings with elevators. As a result, anumber of properties were reclassified (DOBDecember Tags). Of the roughly 8,700 buildingsreceiving DOB December Tags, approximately1,300 were given yellow tags, and 780 weregiven red tags, of which 230 were further categorized as destroyed.

Though the figures diverge from one another,the story that they tell about the impact ofSandy on the city’s building stock is relativelyconsistent. Namely that, with respect to thebuildings that were seriously damaged bySandy (those receiving either yellow or redtags, including those further classified as destroyed), the majority (between 63 percentand 91 percent) received yellow tags. This indicates that most Sandy-related damage wasnon-structural in nature, largely due to floodingof building systems and equipment (includingelectrical, sanitary, and life safety systems) located on ground floors or in basements—aconclusion that is buttressed by the fact thatthe aforementioned figures likely understatethe number of buildings citywide that couldhave received yellow tags, given that DOB’s

focus was generally on areas of the city wherestructural damage to buildings was greatest.

Though the damage indicated by yellow tags,in most cases, did not structurally compromisebuildings, it did, in many cases, have profoundimpacts on building occupants, displacing residents and businesses likely also to be contending with extensive damage to buildingcontents. Some yellow tagged buildings also re-quired significant and costly repairs, includingwork on ground floors and basements.

Two sets of factors proved to be strong predictors of how Sandy affected buildings.First, flood characteristics such as surge forceand depth of inundation correlated stronglywith the degree of damage suffered by a building. Thus, shoreline areas that experiencedthe strong lateral forces of waves had manymore damaged buildings than areas with stillwater flooding. In fact, wave action along theAtlantic Coast (including Southern Brooklyn,South Queens, and the East and South Shoresof Staten Island) accounted for the majority ofdamaged buildings, and for nearly all buildingstagged red or destroyed citywide, whetherthose tags were DOB Pre-Storm Tags or DOB De-cember Tags. (See chart: Buildings Assigned Redor Destroyed Tags, Categorized by Flood Type)

Other, perhaps less intuitive, predictors ofSandy’s impact on any given building includedbuilding age and physical characteristics. Forexample, buildings predating the 1961 ZoningResolution and the 1983 FIRM standards faredmuch worse than newer buildings, more frequently sustaining significant damage. Moreover, where more recently constructedbuildings did suffer damage, such damagetended to be moderate rather than severe.


Stillwater Flooding (Upper Harbor)Surge & Wave Action (Atlantic Coast)

97%

3%

Source: DOB December Tags, DCP PLUTO

Buildings Assigned Red or Destroyed Tags, Categorized by Flood Type


Building height was another key predictor ofthe degree of building damage from Sandy.One-story buildings proved particularly suscep-tible to severe damage. Although such buildingsaccounted for less than 25 percent of the build-ings in the area inundated by Sandy, they rep-resented roughly 75 percent of the buildingsthat sustained the most severe damage accord-

ing to the DOB December Tags (those receivingred tags, including those further tagged as destroyed). By contrast, high-rise buildings experiencing inundation generally did not sustain structural damage according to theDOB December Tags. They, however, often didexperience damage to building systems thatwere housed in basements or otherwise

insufficiently elevated. (See chart: Buildings Assigned Destroyed, Red, and Yellow Tags,Categorized by Building Height)

Construction type, which tends to correlatewith building height, also served as a predictorof Sandy-related damage for buildings. Asstated above, low-rise structures suffered themost severe damage. Though such structuresare often of combustible construction, not allare. However, where low-rise structures werealso of combustible construction, the damagetended to be even more severe. In fact, while85 percent of the 1-story buildings in the areainundated by Sandy were combustible struc-tures, 99 percent of 1-story buildings receivingred DOB December Tags (including those further tagged as destroyed) were of a combustible construction type. Conversely,high-rise structures, which often are of a non-combustible construction type, tended toexperience less severe structural damage. (Seephotos: Combustible Construction Type andNon-Combustible Construction Type)

The building type most vulnerable to Sandy’s effects turned out to be 1-story combustiblebuildings constructed before 1961—includingbungalows found in many coastal areas of thecity. Buildings matching these characteristicsrepresented 18 percent of the buildings in theinundated areas of the city, but 73 percent of allstructurally damaged or destroyed buildings inthe city. Structures of this type were approxi-mately four times more likely to sustain severedamage than their share in the inundation areawould suggest. (See chart: Share of Total Buildings in the Sandy Inundation Area Compared to Share of Building Damage, Categorized by Building Type)

Combustible structures, such as the wood stud-frame building above, tend to be lighter and shorter and suffered more severe structural damage during Sandy.

Non-combustible structures, such as the reinforced concrete frame buildingabove, tend to be heavier and bigger, and primarily suffered non-structuraldamage to building systems and equipment during Sandy.

Combustible Construction Type Non-Combustible Construction Type

Credit: Devin Ford Credit: Jeramey Jannene

Yellow Tag

Red Tag

Destroyed

7+ Floors3-6 Floors2 Floors1 Floor

43%

39%

18%

68%

6%

25%

87%

9%

4%

99%

1%

Buildings Assigned Destroyed, Red, and Yellow Tags, Categorized by Building Height


76CHAPTER 4 | BUILDINGS

Share of Total Buildings in the Sandy Inundation Area Compared to Share of Building Damage, Categorized by Building Type

Year of Construction CombustibleNon-

Combustible CombustibleNon-



Combustible

Pre-1961 18% 3% 37% 1% 11% 1% 0% 1%

100%

Post-1961 2% 1% 16% 1% 6% 1% 0% 1%

Pre-1961 73% 1% 16% 0% 5% 0% 0% 0%

100%

Post-1961 1% 0% 3% 0% 1% 0% 0% 0%

Tota

l Bui

ldin

gsB

uild

ings

Ass

igne

d Re

d or

Des

troy

ed T

ags

Although both size and construction type didplay a role in the poor performance of manydamaged and destroyed 1-story buildings, it isnoteworthy that other 1-story structures andother combustible structures generally did notfare as poorly as 1-story combustible structuresthat also were built prior to the introduction ofmodern building codes. Thus the rules and regulations contained in these codes did appearto have played a particularly critical role in determining how well impacted structures fared.

What Could Happen in the Future

New York City’s buildings face a variety of risksrelated to climate change.

Major Risks Now and into the future, the risk of storm surgecombined with sea level rise is likely to presentthe greatest threat to New York City’s buildingstock. Flood risk is illustrated by the recentPWMs created by FEMA, which show more than67,700 buildings now to be in New York City’s100-year floodplain, up from the approximately35,500 indicated in the 1983 FIRMs—an increaseof roughly 90 percent. These 67,700 buildings,in turn, encompass nearly 535 million squarefeet of space and house approximately 398,000

Percentages reflect the share of buildings in each category – either Total Buildings in the Sandy Inundation Area or Buildings with Red or Destroyed Tags– that have the characteristicsdefined in the chart. For example, 1-story buildings of a combustible construction type built pre-1961 represented 18 percent of the buildings in the Sandy Inundation Area, but 73percent of the buildings tagged red or destroyed.


1 Floor 2 Floors 3 to 6 Floors 7 Floors or Higher

Expansion of the Number of Buildings in the 100-Year Floodplain

Bronx

Brooklyn

Manhattan

Staten Island

Queens

2013 PWMs1983 FIRMs

Total: 35.5K

Total: 67.7K

11.2K

23.5K

3.0K

25.8K

4.2K

8.0K

13.9K

2.1K

7.3K

4.2K

Source: DCP, FEMA

Buildings in the Sandy Inundation Area

Risk Assessment: Impact of Climate Change on BuildingsMajor Risk Moderate Risk Minor Risk


Scale of Impact

Hazard Today 2020s 2050s Comments

Gradual

Sea level rise Increasing numbers of buildings face weekly and daily flooding

Increased precipitation

Minimal impact

Higher average temperature

Minimal impact

Extreme Events

Storm surge Large and growing number of buildings likely would face significant flooding risk

Heavy downpour Minimal impact

Heat wave INDIRECT: impact primarily relating to increased risk of power outages

High windsBuilding codes are calibrated to anticipated wind speeds though in-place stock and equipment may be vulnerable

residents and 271,000 jobs. Though these figures are significant in many ways, they tellonly part of the story of the city’s vulnerability.(See chart: Expansion of the Number of Buildings in the 100-Year Floodplain)

As vulnerable as New York’s building stock maybe today, it is very likely to become even morevulnerable in the future. According to climateprojections from the New York City Panel on Climate Change (NPCC) described in Chapter 2(Climate Analysis), sea levels are forecast to risethrough the 2020s and 2050s. During this pe-riod, the floodplain will expand, with a corre-sponding increase in the number of buildings inthe 100-year floodplain—rising to more than88,000 by the 2020s and more than 114,000 bythe 2050s based on recent high end projectionsof sea level rise. In addition to exposing moreNew Yorkers to greater risk, an expansion ofthis scale also would have significant financialimpacts on hundreds of thousands of New Yorkers, ranging from new requirements relating to flood insurance, to more expensiveflood insurance premiums, to new requirementsfor property owners to alter ground-level and underground spaces to comply with national flood-resistant construction standards(see Chapter 5).

Other Risks Going forward, high winds are projected topose a moderate risk to the building stock ofNew York.

While the NPCC does not provide specific projections for wind speeds, their projectionsdo suggest an overall increase in the frequencyof the most intense hurricanes, which are ac-companied by high winds. Though the BuildingCode already requires new and substantially improved buildings to protect against topwinds associated with a Category 3 hurricane,older buildings that predate modern standardsand have improperly installed and maintainedexternal elements may be vulnerable. This is especially true in areas with open exposures—for instance, along the coast—and with respectto older 1- and 2-family homes. And all structures, including high-rise buildings, willcontinue to face potential damage to façadesfrom airborne debris during the sorts of extreme wind events that could occur in the future.

In addition, the city’s future wind risk profile inthe face of climate change is uncertain. Whilecurrent Building Code requirements are basedon data from area airports—John F. Kennedy

International Airport, LaGuardia Airport andNewark Liberty International Airport—a detailedmapping of the city's wind profile could providea much more accurate assessment of the risksthat buildings face with potentially increasedstorm activity.

Meanwhile, heavy downpours, increased precipitation, and higher temperatures in thefuture are expected to have a minimal impacton buildings. Though increased precipitationmay raise the possibility of flooding, the levelsof flooding currently projected are not believedto present anywhere near the same threat tolife and property that storm surge poses nowand in the future. Similarly, currently forecastedincreases in average temperatures should notaffect significantly the resiliency of buildingstructural elements or in-house mechanical andelectrical systems. However, without resiliencyinvestments, the power outages that may come with heat waves certainly would affectthe occupants of the city’s buildings (see Chapter 6, Utilities).

Overview and Approach

As the impact of Sandy demonstrated, build-ings constructed in accordance with moderncodes and standards tend to be better able towithstand extreme weather events—that is,they tend to be more resilient. Yet these codesand standards cannot remain static. They mustevolve continually to incorporate the best available technologies and methodologies. Thebuilding initiatives to address climate risks,therefore, include a focus on enhancements toNew York’s building codes, with the goal ofachieving two ends:1. Strengthen new and substantially improved

buildings to meet the highest possible standards;

2. Protect existing buildings—which remain thecity’s biggest challenge given their numbers—by encouraging targeted retrofits over time.

Strengthen new and rebuilt structures to meet the highest resiliency standardsmoving forward For new and substantially improved buildings(that is, buildings for which the cost of alteration is greater than 50 percent of theirprevious value), the highest resiliency standards can be incorporated early in the design phase of construction in a manner thatwould effectively mitigate future losses. TheCity, through the Mayor’s Office of Long-TermPlanning and Sustainability (OLTPS), thereforewill work with the City Council to enhance the

Construction Codes so that these buildings aredesigned to reflect the best available informationon climate risk and resiliency.

Retrofit as many existing buildings aspossible to improve resiliency Meanwhile, the City also must deal with its sub-stantial in-place inventory of existing buildingsthat are or will be vulnerable to climate risks. Inmany ways, existing buildings represent a bigger challenge than new buildings. Most ofthe buildings in the city’s 100-year floodplainare older, constructed to codes and standardsthat did not incorporate flood resistance. Infact, approximately 72 percent of the structuresin the city’s 100-year floodplain were erectedbefore 1961, when the current Zoning Resolu-tion was passed, and 85 percent before 1983,when the City adopted FEMA’s flood maps andincorporated flood-resistant construction standards for new and substantially improvedbuildings in the 100-year floodplain.

New York City’s buildings also, in many cases, canbe found amid urban site conditions that makeretrofits challenging. The city’s building stock differs dramatically from that of communities inother coastal flood-prone areas, such as the GulfCoast and the Southern Atlantic Coast, whichhave sought to incorporate flood resistance eveninto their preexisting building stock. While construction in these coastal areas consistsprimarily of lower-density homes, buildings inNew York City’s 100-year floodplain include substantial numbers of higher density, and often

attached multi-family, and commercial/nonprofitbuildings. Thus, while more than 70 percent ofthe 67,700 buildings in the 100-year floodplain ofFEMA’s PWMs are 1- and 2-family homes, a ma-jority of the building area and housing units in thefloodplain can be found in higher-density build-ings. Specifically, approximately 34 percent ofthe 535 million square feet located in the 100-year floodplain can be found in multi-familybuildings or mixed-use structures (which alsotend to be multi-family), and roughly 39 percentcan be found in commercial/nonprofit space.Similarly, while 1- and 2-family homes representonly 24 percent of the approximately 249,000housing units in the 100-year floodplain, roughly76 percent can be found in multi-family or mixed-use buildings. (See chart: Buildings, BuildingArea, and Housing Units in the 2013 PWMs Broken Down by Land Use)

The very nature of the city’s structural inventoryposes a challenge to using methodologies suchas elevation to retrofit New York’s building stock.For example, many property types common inNew York City’s neighborhoods have multiplestories and are constructed from materials suchas masonry and concrete that make elevation dif-ficult. Many also are attached or semi-attached,which means that elevation would require coor-dination with neighboring properties, and maybe physically difficult and financially infeasible.Additionally, whereas in other jurisdictions, aban-donment of ground floor and underground spacemay be a viable alternative to actual elevation, inmany parts of New York, because of the high


Multi-Family

1- and 2-Family

Commercial/Non-profit

Mixed Use

Other

Number of Housing UnitsBuilding Area (SF)Number of Buildings

72%

12%

3%

8%

5%13%

39%

10%

24%

14%

24%

55%

21%

Total: 67.7K Total: 534.8M Total: 249.3K

Buildings, Building Area, and Housing Units in the 2013 PWMs Broken Down by Land Use

INITIATIVES FOR INCREASING RESILIENCY IN BUILDINGS

Source: FEMA, DCP PLUTO

This chapter contains a series of initiatives thatare designed to mitigate the impacts of climatechange on New York’s buildings. In many cases,these initiatives are both ready to proceed and have identified funding sources assignedto cover their costs. With respect to these initiatives, the City intends to proceed withthem as quickly as practicable, upon the receipt of identified funding.

Meanwhile, in the case of certain otherinitiatives described in this chapter, thoughthese initiatives may be ready to proceed, theystill do not have specific sources of funding assigned to them. In Chapter 19 (Funding), theCity describes additional funding sources,which, if secured, would be sufficient to fundthe full first phase of projects and programs de-scribed in this document over a 10-year period.The City will work aggressively on securing thisfunding and any necessary third-party ap-provals required in connection therewith (i.e.,from the Federal or State governments). However, until such time as these sources aresecured, the City will only proceed with those initiatives for which it has adequate funding.


value of usable real estate, doing so would resultin significant financial loss to property owners.

Greater flood protection in developed areas alsoposes urban design challenges—both for retrofitting and new construction. Such protec-tion can interfere with the visual connectivitybetween the first floor of a building and the public sidewalk, creating uninviting entrance-ways, and leading to architecture that fails toengage pedestrians. In New York, traditionalflood-protection methods, therefore, have thepotential to impact the neighborhood fabric ina negative way and could undermine the vitalityof street life.

For example, if buildings in dense urban areasare elevated, spaces left unoccupied at thestreet level could pose security risks to area residents. Elevation also can make commercialcorridors—which provide critical services andemployment—untenable by inhibiting accessto street-level retail. Visual and physical acces-sibility of retail from the sidewalk is more impor-tant in New York than elsewhere because NewYorkers walk to shopping and services morethan anyone else in the United States. Elevatingstores also can isolate them from the street en-vironment. In addition, dry flood-proofing of re-tail or industrial structures can be technicallydifficult or costly. Meanwhile, even where ele-vation may be physically possible (as in the caseof smaller, wood-framed structures), the nar-row lots in New York City limit the space neededto stage construction and make post-elevationaccess challenging. (See sidebar: Urban SiteConditions and Flood Protection Challenges)

In short, these and other constraints make it prohibitively expensive, physically infeasible, orboth, for owners of many properties in the flood-plain to elevate their structures or to otherwiseretrofit their buildings to meet national flood-resistant construction standards in full. In fact, asof the writing of this report, it is estimated thatowners of approximately 39 percent of buildingsin the 100-year floodplain of the PWMs (orroughly 26,300 buildings) would face significantchallenges if they sought to retrofit in these waysdue just to their challenging site conditions suchas narrow lots or attached structures—withouteven taking into account issues such as cost andthe ability to secure financing.

Given these obstacles, some policy advocateshave suggested alternative approaches to im-prove the resiliency of New York’s housing stock,such as government purchases of large numbersof vulnerable properties in the floodplain. Buyouts intended to turn exposed propertiesinto natural or open spaces may make sense inlimited circumstances in very high-risk areaswhere vulnerability is a function of the land itself,

and not of shortcomings in the buildings thatexist there as of the writing of this report. How-ever, such buyouts raise many issues. They wouldneed to result in an open space or buffer area thatserves a useful purpose, and to do so, would require near-unanimous participation of area residents to be effective—a challenge in many circumstances. Additionally, even if unanimity (ornear-unanimity were achieved), the approach canbe expensive—diverting limited resources fromother investments that may be more cost-effective or have a more widespread impact.Given the scale of New York’s building stock in thecoastal area, the fact that buildings can be constructed to address the flood risks faced inthe vast majority of coastal neighborhoods, andthe limited alternative options for a growing pop-ulation in New York City and the region, wholesaleabandonment of or retreat from the city’s waterfront is simply not a practical option.

The City, therefore, proposes an approach pursuant to which buyouts would be a tool inthe City’s tool kit, but one that would be usedsparingly and, where used, would most com-monly be used with the goal of redeveloping ac-quired properties in a more resilient fashion. Inmost cases, the City will prioritize the use of limited resources to retrofit the largest numberof existing buildings to a significantly higherstandard of resiliency. This strategy focuses onavoiding catastrophic loss in building types thatproved most vulnerable during Sandy and otherwise seeks to allow inhabitants to reoccupybuildings quickly—after complying with all Cityevacuation orders and once reentry is deemedto be safe—by focusing efforts on elevating orotherwise protecting critical building systems.As with all retrofits, these building improvementswould be completed in compliance with existing City construction rules, including therequirement that alterations greater than 50 percent of building value, prior to improve-ment, be considered “substantial improve-ments.” Substantially improved buildings mustcomply with the same flood-resistant construc-tion standards as new buildings.

Strategy: Strengthen new andsubstantially rebuilt structuresto meet the highest resiliencystandards moving forward

Initiative 1 Improve regulations for flood resiliencyof new and substantially improved buildings in the 100-year floodplain

As described above, the current rules for flood-resistant construction incorporate elevationsfrom the most recently adopted FEMA FIRMs,

which have not been significantly updatedsince 1983. In 2010, FEMA began working withthe City to update these maps to reflect betterinformation on current flood risk. As part of thiseffort, FEMA released PWMs in June 2013.These maps provide an updated approximationof the final boundaries of the floodplain andBFEs that will be found in the final FIRMs thatare expected to be issued by FEMA in 2015,with City adoption thereafter.

To enable new and substantially improvedbuildings, as well as existing buildings thatretrofit voluntarily, to withstand appropriateflood risk, the City has proposed an amendmentto the Zoning Resolution to allow these buildingsto be elevated, without being penalized by zoning height limitations, to the higher of theBFE in the current effective FIRMs or the bestavailable flood maps (currently the PWMs), ineach case, plus 1 to 2 feet of freeboard. Theproposed changes would also allow additionalflexibility for other resiliency measures, includingthe elevation of mechanical equipment and relocation of existing underground parking.

When the new FIRMs are finalized, the City willfurther update the Building Code to referencethe elevations contained therein and to requirefreeboard of 1 to 2 feet above these elevations.

Looking to a future where sea level rise couldresult in flood elevations even beyond the mandated freeboard, the City also will conducta study of the implications of permitting zoningrelief for up to 3 feet of freeboard. This analysiswill serve as a necessary first step towards potential future adoption of corresponding zoning changes.

Towards a similar end, the City and the NPCC willestablish a set of interim metrics to be measuredin 2025 that will indicate whether sea levelsaround New York appear to be rising at expectedrates. Every six years—in conjunction with everysecond Construction Codes review cycle—theNPCC and the City will review observed sea levelrise. If, by 2025, sea level rise surpasses the metrics put forth by the City and the NPCC, theBuilding Code will be amended at that time, withcorresponding zoning relief, to require 3 feet offreeboard above the BFE in FEMA’s FIRMs (ratherthan the proposed 1 to 2 feet).

The Construction Codes (of which the BuildingCode is a part) will be amended in yet otherways, including additional changes that willhelp protect building systems and enable continued building operation in the event ofutility failures during a flooding event. For example, new and substantially improved build-ings in the 100-year floodplain will be requiredto install backflow preventers for sewer


80CHAPTER 4 | BUILDINGS

connections, to seal points of entry further fromfloodwaters, and will be required to safeguardtoxic materials.

The Construction Codes also will be amendedto reduce restrictions on the length of cablesthat carry telecommunications service, allowingthese cables to reach elevations above the DFE.

In addition, the City will revise existing provisionsthat restrict options for elevating critical equipment. For example, to encourage buildingowners to protect fuel tanks from flood damage,the current limits on the size of fuel tanks located above grade will be revised to allow formore flexibility. Also, DOB will issue a clarificationon how mechanical equipment rooms contributeto floor area in a building.

In 2013, the City, through OLTPS, will seek to implement the foregoing changes to the Construction Codes. Also in 2013, DCP will continue to take the foregoing zoning changesthrough the public review process, with the goalof adoption before the end of the year. By 2015,DCP also will launch an analysis of the implica-tions of allowing up to 3 feet of freeboard abovethe BFE, pending the scheduled release of thefinal FIRMs.

Initiative 2 Rebuild and repair housing units destroyed and substantially damaged by Sandy

Roughly 23,000 private residential buildings encompassing nearly 70,000 housing units sustained some level of damage during Sandy.More than 2,000 of these buildings were signif-icantly damaged and must be completely rebuiltor substantially improved , incorporating thehighest resiliency standards . To address thedamages sustained and to more effectivelyprepare these significantly damaged buildingsfor future storm events, the City either will assistowners or, in limited cases meeting City criteria,will facilitate the acquisition of properties bynew owners whom it will assist, in rebuildingand substantially improving these propertiesbased on the best floodplain data available overtime. Additionally, the City will seek to incorpo-rate resiliency measures into approximately 500to 600 multi-family properties that sustainedminor damage, including those developedunder the City's Mitchell Lama Program andother affordable housing programs.

The Mayor’s Office of Housing Recovery Opera-tions (HRO) and HPD will lead these efforts. Federal Community Development Block Grant(CDBG) funding in the amount of approximately$530 million has been allocated to the firstphase of these programs. HRO and HPD plan to

As described previously, site conditions in New York City make it both physically and financially difficult for the owners of many buildings in the 100-year floodplain to retrofit their buildings to current Federal flood-resistant construction standards. These challenges come into sharp focus when common building types in neighborhoodsacross New York City are examined.

Urban Site Conditions and Flood Protection Challenges

Credit from top to bottom: Tim F via Flickr, WikiMedia, mercurialn via Flickr, Gryffindor via WikiMedia, Adam Elmquist via Panoramio

INDUSTRIAL BUILDINGSThough Federal flood-resistant constructionstandards allow dry flood-proofing of industrial spaces, this approach is costly and less reliable for flood levels higher than 3 feet.

Howard Beach, Queens

Bayside, Queens

Sheepshead Bay, Brooklyn

Red Hook, Brooklyn

South Street Seaport, Manhattan

1- AND 2- FAMILY HOMES ON NARROW LOTSNarrow lots lack space needed to stage construction when elevating a building.

ATTACHED AND SEMI-ATTACHED HOMESReconfiguration of one building affects adjoining ones, and, with multi-story buildings, elevation requires removing floors and front and rear facades, in effect demolishing and rebuilding.

MULTI-STORY BUILDINGSThese buildings would, under current Federalflood-resistant construction standards, either have to eliminate all ground-floor and basement units, displacing families and forfeiting rental income, or elevate, which is highly impractical.

BUILDINGS WITH COMMERCIAL GROUND FLOORSCommercial spaces thrive on ground-fl oor access. Raising the lowest floor to higher base flood elevations hampers commerce and complicates accessibility.



use a portion of these funds to repair and re-build a subset of properties that were damagedsignificantly and, therefore, must be rebuilt orsubstantially improved.

Initiative 3 Study and implement zoning changes toencourage retrofits of existing buildingsand construction of new resilientbuildings in the 100-year floodplain

The City, through DCP, will undertake a series ofcitywide and neighborhood-specific land usestudies to address key planning issues in se-verely affected and vulnerable communities. Aspart of these studies, the City will identify waysto facilitate the voluntary construction of new,more resilient building stock and to encouragevoluntary retrofits of existing vulnerable buildings over time. To be undertaken in closeconsultation with local residents, elected officials, and other community stakeholders,these land use studies will focus in particular onthe challenges posed by the combination offlood exposure of the applicable neighborhoods,the vulnerability of the building types that arefound in these neighborhoods (e.g., older, 1-story bungalows) and site conditions in theseareas, such as the narrow lots in Midland Beachthat can make replacement or retrofit of vulner-able buildings expensive or complicated.

Both citywide zoning changes and detailedneighborhood studies will promote the volun-tary development of new, resilient buildingsthrough strategies such as: • allowing more flexibility in the measurement

of height of elevated buildings and allowingparking to be placed underneath, providedsteps such as landscaping are taken to address the quality of the streetscape; and

• enabling or even encouraging construction ofnew buildings that meet modern standardson existing small lots, either individually or incombination with other lots to be rebuilt.

Zoning changes to encourage the voluntaryretrofit of existing buildings could include: • permitting building owners to construct an

additional floor above existing top floors to replace space below the DFE that is limited inuse to meet flood protection standards;

• promoting best practices for the alternativeuse of ground floor space below the DFE,where Federal flood-resistant constructionstandards do not permit residential uses andmay not permit commercial or other uses;

• increasing the building space allowed for me-chanical systems, enabling property ownersto more easily elevate building systems; and

• permitting greater flexibility in the design ofstairs, ramps, and other accessibility features

where elevation is required for flood-protec-tion purposes.

DCP’s proposed Flood Resilience text amend-ment addresses some of these issues on a city-wide basis. Subject to available funding, the goalis for DCP to commence additional studies in2013. Thereafter, DCP would move to implementany changes deemed to be appropriate basedon the results of its study.

To supplement these studies as well as post-Sandy housing recovery efforts more broadly,DCP also has worked with representatives ofthe local design community to develop a set ofurban design principles to consider while designing flood-resilient buildings. These principles—included in DCP’s Designing forFlood Risk study to be released in June 2013—can help mitigate the negative impacts of building elevation on streetscape, building ac-cess, ground floor activity, architectural quality,and neighborhood character. (See sidebar: De-signing for Flood Risk: Urban Design Principles)

Initiative 4 Launch a competition to encourage development of new, cost-effective housing types to replace vulnerable stock

Many property owners are facing the realitythat their homes are not only vulnerable to riskssuch as coastal flooding, but shortly they alsomay be facing substantial increases in their in-surance premiums. In some cases, elevation ofexisting structures may be possible; in othercases, however, such elevation may be difficultor even impossible.

Subject to available funding, the City, throughHPD, will launch an international competitioncalled the Resilient Housing Design Competition.This competition will award prizes to private sector developers who design and developnew, high-quality housing prototypes that offerowners of vulnerable building types (e.g., older,1-story bungalows) a cost-effective path that isconsistent with City building and zoningrequirements to replacing these structures. Thewinners of this competition will be given the op-portunity to place these structures into servicein connection with a City-sponsored develop-ment project. Prototypes will have applicabilitythroughout the five boroughs. The goal is forHPD to launch this competition in 2013. Phase 1of the competition will be an open internationalcall for the creation of these prototypes, with afocus, in particular, on prototypes that addresssite conditions that are particularly challenging.Up to 10 winners will be selected for total cashprizes of up to $2 million, awarded by a panelof judges, which, among other considerations,

will evaluate the likelihood that the prototypesactually will be deployed by New York City property owners.

Initiative 5 Work with New York State to identify eligible communities for the New YorkSmart Home Buyout Program

In February 2013, New York State announced aprogram pursuant to which the State would purchase highly vulnerable properties, teardown existing structures, and convert suchproperties into permanent open space. TheCity—through multiple agencies and depart-ments including HRO, HPD, DCP, the Departmentof Environment Protection (DEP), and the Department of Parks & Recreation (DPR)—willevaluate opportunities for collaboration withthe State in connection with this program basedon an objective set of criteria developed by theCity, including extreme vulnerability, consensusamong a critical mass of contiguous local residents, and other relevant factors. It is antic-ipated that the eligibility criteria will be met in arelatively limited number of New York City areas.Funds allocated for this program statewide include $171 million in CDBG funding from NewYork State, together with other State sources.

Initiative 6 Amend the Building Code and completestudies to improve wind resiliency for newand substantially improved buildings

In recent memory, New York City has not beenstruck by a regional wind event. However,though current Building Code requirements arecalibrated to withstand a Category 3 hurricane,as the climate changes, the frequency of extreme wind events is likely to increase.

To address this uncertainty and improve theCity’s approach to protecting buildings fromwind risks, the City will take the precautionarymeasure of amending the Building Code to clarify current wind-resistance specificationsfor façade elements and will restrict the use ofpea gravel and small dimension stone as ballaston roofs. The City, through OLTPS, will implement these Building Code changes in2013. Subject to available funding, DOB also willinitiate a study to help the City more accuratelymap the wind profiles facing New York City’sbuildings across all five boroughs, identifyingsites that face the greatest risk. The goal is tocommence this study in 2013, with completionexpected in 2015.


FEMA and Building Code standards for flood-resistant construction require new or substantially improved buildings in floodzones to be flood-proofed or elevated above projected flood levels. However, elevating buildings more than a few feet abovethe sidewalk can have negative effects on streetscape, building access, public safety, ground floor activity, architecturalquality, and neighborhood character. DCP has worked with representatives of the local design community to develop a setof urban design principles to guide the design of flood-resilient buildings.

Adapting to higher standards of flood resistance is both a challenge and an opportunity for architects to achieve higher standards of design. The opportunity exists to innovate and produce buildings that contribute to the public realm and have a positive long-term effect on those neighborhoods recovering from Sandy.

Designing for Flood Risk: Urban Design Principles

NEIGHBORHOOD CHARACTERSome neighborhoods exhibit a relative uniformity of building form. Elevating buildings will necessarily produce variations in building height and, in some cases,placement on the lot. Designers should respect a neighborhood’s character by taking cues from existing context in building massing, fenestration, rooflines, andother architectural elements.

Source: DCP

VISUAL CONNECTIVITYHaving the windows and front door of a building face the public street can create asense of security and comfort for pedestrians. These architectural elements alsoprovide visual interest, which in turn promotes a walkable neighborhood. Elevatingthe first floor of a building can limit this visual connectivity. In residential neighbor-hoods, porches, stoops, and generous access elements can be designed in orderto help to mitigate this disconnection. On commercial streets, this visual connectiv-ity is important to the viability of local retail. A common best practice would be todry flood-proof the commercial space so that it can be closer to sidewalk level andtherefore maximize visual and physical connectivity.

FACADE ARTICULATIONBuildings often contribute to the character of a place by offering human-scale ar-chitectural elements, particularly on first floors. Elevated buildings with crawlspaces, parking, or storage can create blank walls at grade. Setting a building backfrom the property line slightly and using landscaping and/or other creative designsolutions could help to buffer these voids in an active streetscape. If ground-levelparking is the only feasible option, then garage doors and curb cuts should be designed to minimize their impact on the pedestrian realm.

INVITING ACCESSElevated buildings pose challenges for accessibility. Ramps can be difficult to ac-commodate, particularly on smaller lots. Even smaller buildings that are not requiredto meet Americans with Disabilities Act (ADA) standards have the challenge of integrating longer runs of stairs into building or landscape design. Introducing a 90-degree turn or landing, and paying careful attention to overall stair design couldmake a long run of stairs easier to climb and appear more inviting for pedestrians.



Strategy: Retrofit as manybuildings as possible so thatthey will be significantly moreresilient than they are today

Initiative 7 Encourage existing buildings in the 100-year floodplain to adopt flood resiliencymeasures through an incentive programand targeted requirements

The City will propose a program that will encourage and, in some limited cases, requireproperty owners to adopt targeted flood protection measures that are tailored to New York’s dense urban environment and thatwill offer meaningfully greater protection than the status quo.

This program consists of two elements: • an incentive program, which will fund a

portion of eligible flood-protection costs forexisting building stock, subject to availablefunding; and

• a requirement for large buildings—those with 7 or more stories that are more than300,000 square feet in size—to undertakeflood-protection measures by 2030.

Incentive Program With the goal of ensuring that the vast majorityof the built square footage currently in the 100-year floodplain is significantly better protectedfrom flood risk going forward than prior toSandy, the City will create, subject to availablefunds, a $1.2 billion program that will offergrants or, where appropriate, loans to buildingowners to help fund a percentage of the eligiblecosts of completing all or some of the CoreFlood Resiliency Measures (as defined below).

The actual percentage of costs covered by thisprogram will be based on a sliding scale, takinginto account the uses of the applicable building(as defined by Department of Finance (DOF) tax class), the applicable building’s size, andbuilding value (using assessed value as aproxy). Prior to implementation of this program,the City will publish for public comment a proposed methodology for calculating theaforementioned sliding scale. Subject to the discretion of the City in cases of great need,the City will cap awards at $2 million per building.

Core Flood Resiliency Measures: As Sandydemonstrated, during an inundation event,damage to systems and equipment is the mostcommon type of damage experienced by buildings. In addition to imposing costly repairs,

damage to systems and equipment also delaysrecovery, preventing people from reoccupyingtheir homes and getting their businesses up and running quickly after a storm.

The Core Flood Resiliency Measures will there-fore include elevation or other flood protectionof the following critical building equipment andutilities: fire protection equipment (includingalarms and pumps); electrical equipment (including panels, switch gear, and transform-ers); heating, ventilation, and air conditioning(HVAC) equipment (including boilers, furnaces,and burners); plumbing equipment (includingdomestic water equipment and sump pumppower feeds); telecommunications equipment;elevator equipment; and emergency genera-tors and associated fuel tanks and pumps (sub-ject to the approval of the Code amendmentsdescribed above). (See graphic: Flood Protec-tion of Building Systems)

Elevation or flood-proofing of this equipmentwill be required to meet the standard of thehigher of the BFE, as set forth in the PWMs, orthe FIRMs in effect as of the writing of this re-port, in each case, plus 1 to 2 feet of freeboard(as applicable). Upon adoption of the newFIRMs, elevation will be required to meet thestandard of the BFE, as set forth in the newFIRMs, plus 1 to 2 feet of freeboard (as applicable).

For owners of 1- to 2-story buildings of a combustible type—those buildings most at riskof severe structural damage during a flood—Core Flood Resiliency Measures also will include structural reinforcement to prevent collapse in the event of inundation, including:• upgrades to the foundation; • reinforcement of exterior walls; and • wet flood-proofing (see above).

These measures do not suggest that inhabi-tants should remain in their buildings during aflood or storm surge event. Regardless of theinterventions completed, all residents and businesses should, of course, comply with anyCity evacuation orders to promote their safety.However, the goal is for the retrofits proposedabove to allow residents and businesses to recover more quickly after a storm, once reentry is deemed to be safe.

Disbursement of Funds: For the first one to two years of the program, funds will be allocated to specific categories of uses to enable an equitable distribution of such fundsacross building types and geographies. Categories for which funds will be set aside duringthis one to two year period will be the following: • $100 million reserved for 1- to 3-family homes

(DOF tax class 1);

Flood Protection of Building Systems

K

DFE

Example of a building hot water heater and furnace elevated above the minimum flood protection level via a platform.


• $500 million to be divided among the boroughs based on their share of buildings inthe 100-year floodplain; and

• $100 million reserved for affordable housingprojects (i.e., projects where at least 50 per-cent of units have income restrictions pursuantto a regulatory agreement, or projects other-wise designated as “affordable” by the HPD Commissioner).

At the end of the initial one to two year periodof the program, any reserved funds that remain unused will be made available to all eligible applicants.

The Core Flood Resiliency Measures incorpo-rate lessons learned from FEMA’s work in assessing the damage from Sandy, as well asguidance from FEMA’s extensive experiencewith building mitigation. Yet existing NFIP rulesdo not offer insurance rate reductions for build-ings that become materially less vulnerablewith these retrofits. To address this challenge,the City will continue to work with FEMA to develop a system of mitigation premium creditsthat reduce the cost of insurance for propertyowners who invest in these and other alternative approaches (see Chapter 5).

New York City Economic Development Corporation (NYCEDC) and HPD will administerthis program beginning in 2013. The City willpursue CDBG funds as well as Federal HazardMitigation Grant Program (HMGP) funding, andother new sources, for the required funding forthe program (see Chapter 19, Funding).

Mandate for Large Buildings In addition to the incentive program outlinedabove, the City also will require buildings in the100-year floodplain that are 7 stories or tallerand greater than 300,000 square feet in size tocomplete Core Flood Resiliency Measures by2030, so that the City’s largest buildings are notknocked out of service by future flood events.

Given the structural stability of buildings of thissize, this mandate will apply to elevation orflood-protection of building equipment and util-ities as described above, but will not requirestructural reinforcements. This mandate will beimplemented via a change to the City’s BuildingCode and will be administered by DOB.

This mandate will not apply to public housingdevelopments—which are pursuing a parallelresiliency program—or hospitals, nursinghomes, and adult care facilities—which will be subject to a different mandate (see Initiative9, below, and Chapter 8, Healthcare). The mandate will apply to affordable housing projects. However, because of the sometimesprecarious financial position of such projects,

they will be entitled to apply for a hardshipwaiver from the HPD Commissioner. Buildingssubject to the mandate will be eligible to applyfor funds through the incentive program described above.

With respect to buildings subject to this man-date, there will be two ways to achieve compli-ance. One will be a more traditional compliancetrack, pursuant to which building owners willcomplete one of the following approved flood-protection strategies:• elevation of applicable equipment and utilities

at or above the applicable DFE; • dry flood-proofing of equipment and utilities

below and up to the applicable DFE; and • dry flood-proofing of the building itself below

and up to the applicable DFE.

Buildings subject to the mandate also will be of-fered an alternative compliance track, pursuantto which building owners will be deemed to havesatisfied the mandate, provided that they havetaken one of the following steps:• put in place alternative building-based

measures (for example, temporary barrierscoupled with an action plan; regular drills bytrained staff; and renewal certificates) thatprovide an equivalent level of protection tothe traditional path, as certified by a struc-tural engineer and approved by DOB; or

• achieved protection via a coastal defense system that protects the applicable buildingup to the applicable DFE, as certified by astructural engineer and approved by DOB.

Notwithstanding the foregoing, the alternativecompliance track will not be available for thefollowing life safety systems: emergency gen-erators and associated fuel tanks and pumps(subject to the approval of the Code amend-ments described above); fire alarm systemcomponents; fire pumps (to the extent thatsuch components are not submersible); domes-tic water systems (to the extent that compo-nents are not submersible); and sump pumppower feed equipment.

In addition, property owners may appeal toDOB for a variance from the mandate if site con-straints or other engineering factors rendercompliance impossible. The BSA also will be au-thorized to grant such variances.

The City will seek City Council approval for thismandate—through a Building Code change—by the end of 2013. When first implemented,DFEs will be as set forth in the PWMs. Uponadoption of the new FIRMs in 2015, DFEs will beas set forth therein.

Compliance with the mandate will be monitored by the City in two ways. First, by the

end of 2020, subject buildings owners will be required to submit an interim report certify-ing that they have complied with the mandate,or to submit an affidavit describing a plan to achieve such compliance by 2030. Any build-ings that become subject to this mandate in thefuture as flood maps are revised will have 15years from the date that the applicable map isadopted to comply with the mandate.

Initiative 8Establish Community Design Centers toassist property owners in developing design solutions for reconstruction and retrofitting, and connect them toavailable City programs

Property owners in neighborhoods affected bySandy, or other potentially vulnerable areas inthe 100-year floodplain, are working to under-stand how to rebuild or retrofit their buildingsto be prepared for future extreme weather. TheCity, through HRO, will work with local partnersand advocates to establish a physical presencein affected neighborhoods across the city in so-called Community Design Centers, in whicha mix of professional and volunteer design staffwould be on-call to help residents with reconstruction questions. The staff of eachCommunity Design Center will also direct property owners to City programs that facilitatebuilding repair and resiliency. The Centers couldbe managed by the City with support from local partners.

Initiative 9 Retrofit public housing units damaged bySandy and increase future resiliency

New York City Housing Authority (NYCHA) de-velopments across the city sustained significantdamage during Sandy, including damage toelectrical systems in approximately 250 NYCHAbuildings. To address this issue, the City will im-plement targeted efforts to strengthen buildingresiliency against future extreme weatherevents by designing and constructing improve-ments to public housing directly impacted by Sandy.

Federal CDBG funding in the amount of $108 million has been allocated to this initiative. Thefirst phase of this program will include the instal-lation of permanent emergency generators or al-ternate measures to enhance power resiliencyat NYCHA’s most vulnerable impacted buildings.In addition, a combination of payments fromNFIP policies, commercial insurance policies, andFEMA’s Public Assistance Program may be available to provide funds to cover the cost of re-pairing damaged structures and making resiliencyimprovements on these damaged buildings. Subject to available funding, NYCHA will begin this



work in 2013. By September 2013, NYCHA willalso begin a planning process to identify targetedresiliency measures (for example, raised boilersand electrical switch gear) to address vulnerabilitythroughout buildings in its portfolio in the 100-year floodplain. (See sidebar: New York CityHousing Authority Resiliency Planning)

Initiative 10 Launch a sales tax abatement programfor flood resiliency in industrial buildings

Industrial properties are particularly vulnerableto flood damage, because they tend to be concentrated in coastal areas of the city. Thisvulnerability is heightened since many indus-trial businesses are located in 1- to 2-storystructures and ordinarily store expensive equip-ment and inventory at ground level. Industrialbusinesses also frequently operate on thinprofit margins.

Given this, the City will launch a sales tax abate-ment program directed at industrial businessesto help subsidize the cost of making flood resiliency improvements. The program will pri-oritize 1- to 2-story buildings with more than 4 feet between their actual ground elevationand the applicable BFE.

The New York City Industrial DevelopmentAgency (NYCIDA) will implement this programbeginning in 2013, with total benefits pursuantto the program to be capped at $10 million.

Initiative 11Launch a competition to increase floodresiliency in building systems

Approximately 88,700 buildings were located inareas impacted by Sandy. The number of prop-erties at risk of coastal flooding, meanwhile, islikely to increase through the 2020s and 2050s,as sea levels rise and the floodplain expands.

To address this challenge, the City will launch aResiliency Technologies Competition to allocategrants on a competitive basis to improve build-ing resiliency. The competition will seek to funddemonstration projects that use innovativetechnologies to make building systems moreresilient. NYCEDC will launch this competitionin 2013 and expects to select winners in 2014.Approximately $40 million in Federal CDBGfunding has been allocated to the competition.

Initiative 12Clarify regulations relating to the retrofit of landmarked structures in the 100-year floodplain

A number of vulnerable structures in the city’s100-year floodplain are designated as historiclandmarks. Landmarks have restrictions appli-cable to them that may make it challenging forthe owners of those structures to undertake re-siliency retrofits. Consistent with its underlyingmission and legislation, the Landmarks Preser-vation Commission (LPC), therefore, will clarify

its regulations, with the goal of assisting ownersof landmarked buildings and properties in land-marked districts in the 100-year floodplain whoare contemplating retrofit projects.

Initiative 13Amend the Building Code to improvewind resiliency for existing buildings andcomplete studies of potential retrofits

As indicated above, while the NPCC does notprovide specific projections for wind speeds, itsprojections do suggest an overall increase inthe frequency of the most intense storm eventsthat have wind effects. Older buildings that predate modern standards are particularly vulnerable, especially in coastal areas withopen exposures. In addition, all structures, in-cluding high-rise buildings, will continue to facepotential damage to façades from airborne debris during the sorts of extreme wind eventsthat could occur in the future.

To address these risks, in 2013, the City—through OLTPS—will amend the Building Codeto expand the existing DOB Façade InspectionSafety Program for high-rise buildings to include rooftop structures and equipment. Subject to available funding, DOB also will initi-ate a study of potential wind resiliency retrofitsand their potential costs and benefits, consult-ing with a committee of industry experts. Thegoal is to complete the study by 2016.

The New York City Housing Authority (NYCHA) operates 2,596buildings in 334 developments throughout New York City. Thesedevelopments are home to over 400,000 residents—approxi-mately the size of the entire population of Miami, Florida. Resi-dents include working families, low-income households, seniors,and other vulnerable populations. While these developments arelocated in all five boroughs, there are significant concentrationsof public housing on the waterfront far from the urban core, asin the Rockaways in Queens, or in locations with limited publictransportation, such as in Red Hook in Brooklyn.

In preparation for Sandy’s arrival, therefore, NYCHA was requiredto take important steps to protect its residents and assets—in-cluding implementing evacuation plans in the City’s evacuationzones. Despite these orders to evacuate, many NYCHA residents,like others throughout the city, chose to shelter in place.

Due to the large size and heavy construction of NYCHA buildings,the developments suffered little structural damage. However, in

many cases, building mechanical and electrical equipment inbasements was inundated. A total of 402 buildings housing80,000 residents lost power as a result of the flooding of thesebuilding systems. Though NYCHA and community-based organi-zations worked to address the needs of these residents, the im-pact of the storm damage and the difficulty repairing itdemonstrated the importance of making resiliency investmentsgoing forward.

As part of the recovery and rebuilding process, therefore, NYCHAis working to strengthen its buildings portfolio and incorporatemeasures such as the flood-proofing of critical building systems inareas impacted by Sandy. In addition, NYCHA is analyzing optionsfor increasing the safety of buildings not impacted by Sandy but atrisk of future flooding and other extreme weather damage. Overthe next few months, NYCHA will begin a planning process to iden-tify the best methods for increasing resiliency in vulnerable NYCHAbuildings across the city, a process that will engage resiliency engi-neering experts and elicit input from NYCHA residents.

New York City Housing Authority Resiliency Planning


Initiative 14 Amend the Construction Codes and develop best practices to protect against utility service interruptions

Disruptions to building services—due either tothe failure of in-building systems or of the utilitynetworks on which they rely—can render abuilding unusable during a range of climateevents, such as storms and heat waves. Tobegin to address these risks, the City—throughOLTPS—will develop a list of relevant best prac-tices and, in certain cases outlined below, willamend existing regulations.

The first step that the City will take will be to re-quire, by 2014, common access to potablewater in high-rise multi-family buildings duringemergency situations. This will be done to helpupper-floor residents who may lose access tosuch water in their units in the event of the fail-ure of building electric pumps. The City also willdevelop requirements, beginning in 2013, toenable exit lighting to continue to function during an extended blackout.

Additionally, by 2013, the City will develop bestpractices relating to voluntary backup powergeneration and, will amend relevant codes toallow buildings to comply with these best practices. Proposed code changes will allow forreliable, safe, and resilient alternative fuelsources and cogeneration systems for emer-gency power, as well as building-mounted solarpower. New guidelines for “quick-connect utilityhook-ups” also will be promulgated, facilitatingthe rapid restoration of electricity and heat dur-ing utility outages.

The City will further develop, by 2014, bestpractices for emergency planning relating tolonger-term survivability and will create model“building emergency plans” available to building owners. Among other provisions, themodel plans will encourage large commercial buildings to pre-negotiate disaster recovery agreements with service providers and will en-courage multi-family residential buildings toprovide clear communication protocols for es-sential personnel.

The City also will study, by 2015, strategies tolimit heating and cooling losses through building exterior walls, windows, and roofs. Thepurpose of this study will be to determine howto extend the length of time during whichhomes and businesses can continue to operateafter the loss of electrical power.

Example of large backup HVAC equipment on street Credit: FEMA/Ashley Andujar

Documents

A STRONGER, MORE RESILIENT NEW YORK71 A STRONGER, MORE RESILIENT NEW YORK increasingly high safety standards. While this approach has improved building safety over time, the corollary