Resolution 254-2019 1
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9 MONROE COUNTY,FLORIDA
10 MONROE COUNTY BOARD OF COUNTY COMMISSIONERS
11 RESOLUTION NO. 254 -2019
12
13 A RESOLUTION OF THE MONROECOUNTY BOARD
14 COUNTY COMMISSIONERS ADOPTING FEMA TECHNICAL
15 BULLETIN 0 "USER'S GUIDE TO TECHNICAL ULLEIS"
16 DATED JULY 219 AS REQUIRED PURSUANT TO MONROE
17 COUNTY CODE SECTION 122-2(C)
18
19
20 WHEREAS, Monroe County is currently a participating community in the National
21 Flood Insurance Program (NFIP) and is working on internal County policies to improve upon its
22 interpretation of NFIP regulations; and
23
24 WHEREAS, Monroe County desires to maintain eligibility and improve its standing in
25 FEMA's Community Rating System (CS); and
26
27 WHEREAS, Monroe County Code Section 122-2(c), in part, requires that in interpreting
28 other provisions of this chapter, the building official shall be guided by the current edition of
29 FEMA's 44 CF , and FEMA's interpretive letters, policy statements and technical bulletins as
30 adopted by resolution from time to time by the board of county commissioners;
31
32 N , THEREFORE, BE IT RESOLVEDY THE BOARD OF COUNTY
33 COMMISSIONERS OF M N OE COUNTY,FLORIDA:
34
35 Section 1. Pursuant to Monroe County Code Section 122-2(c), the Board hereby adopts
36 FEMA Technical Bulletin 0 "User's Guide to Technical Bulletins" dated July 2019, a copy of
37 which is attached hereto.
38
39 Section 2. The Clerk of the Board is hereby directed to forward one (1) certified copy of
40 this Resolution to the Building Department.
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1 PASSED AND ADOPTED by the Board of County Commissioners of Monroe County,
2 Florida,at a regular meeting held on the 18th of September, 2019.
3
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6 Mayor Sylvia Murphy Yes
7 Mayor pro tern Danny L. Kolhage Yes
8 Commissioner David Rice Yes
9 Commissioner Heather Carruthers Yes
10 Commissioner Michelle Coldiron Yes
11
12
1. 4, C?1,�At
BOARD OF COUNTY COMMISSIONERS
14 3 �► , OF MONROE,/UN LORIDA
BY:
ee May Syl Murphy
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21 ATTEST: KEVIN MADOK, CLERK
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Developed in Accordance
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NFIP Technical Bulletin 0 / July 2019
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Comments on the Technical Bulletins should be directed to:
DHS/FEMA
Federal Insurance and Mitigation Administration (FIMA) Risk Management Directorate
Building Science Branch
400 C Street, S.W., Sixth Floor
Washington, DC 20472-3020
Technical Bulletin 0 replaces Technical Bulletin 0 (2009), User's Guide to Technical Bulletins Developed in
Accordance with the National Flood Insurance Program.
Cover photograph: Neighborhood in New Orleans, LA, flooded by Hurricane Katrina(August 30, 2005;
photo courtesy of Jocelyn Augustino).
NFIP Technical Bulletin 0 contains information that is proprietary to and copyrighted by the American
Society of Civil Engineers and information that is proprietary to and copyrighted by the International Code
Council, Inc. All information is used with permission.
For more information, see the FEMA Building Science
Frequently Asked Questions website at http://www.fema.gov/ To order publications, contact the FEMA
frequently-asked-questions-building-science. Distribution Center:
Call: 1-800-480-2520
If you have any additional questions on FEMA Building (Monday—Friday, 8 a.m.-5 p.m., EST)
Science Publications, contact the helpline at FEMA- Fax: 719-948-9724
Buildinqsciencehelp@fema.dhs.gov or 866-927-2104. Email: FEMApubs@gpo.gov
You may also sign up for the FEMA Building Science email Additional FEMA documents can be
subscription, which is updated with publication releases found in the FEMA Library at
and FEMA Building Science activities. Subscribe at.https:// https://www.fema.gov/media-library/
service.govdelivery.com/accounts/USDHSFEMA/subscriber/ resources.
new?topic id=USDHSFEMA 193.
Please scan this QR code
Visit the Building Science Branch of the Risk Management to visit the FEMA Building �•
Directorate at FEMNs Federal Insurance and Mitigation Science web page.
Administration at https://www.fema.gov/building-science. 0,
Table of Contents
Acronyms............................................................................................................................................................iii
1 Introduction and Background..........................................................................................................................1
1.1 Intended Audience.................................................................................................................................2
1.2 Purpose of Technical Bulletins.............................................................................................................2
1.3 Synopses of Technical Bulletins (as of June 2019)...............................................................................2
1.4 Organization of Technical Bulletin 0—User's Guide to Technical Bulletins....................................4
2 How to Use the Technical Bulletins.................................................................................................................4
2.1 Minimum NFIP Floodplain Management Criteria..............................................................................4
2.2 Best Practices..........................................................................................................................................5
2.3 Building Codes and Standards..............................................................................................................6
2.4 NFIP Flood Insurance Considerations.................................................................................................7
3 Crosswalk of NFIP Regulations and Technical Bulletins..................................................................................7
4 Key Concepts and Requirements for Structures...........................................................................................14
4.1 Special Flood Hazard Areas................................................................................................................14
4.2 Lowest Floor, Enclosure, and Basement.............................................................................................16
4.3 Substantial Improvement and Substantial Damage...........................................................................16
4.4 Open Foundations in Zone V..............................................................................................................17
5 Acronyms and Key Terms..............................................................................................................................18
5.1 Acronyms Used in the Technical Bulletins ........................................................................................18
5.2 Glossary of Terms Used in Technical Bulletins..................................................................................19
6 Supplemental Information.............................................................................................................................24
6.1 How to Obtain Technical Bulletins.....................................................................................................24
6.2 How to Submit Comments on the Technical Bulletins .....................................................................24
6.3 How to Get More Information............................................................................................................24
6.4 FEMA Regional Offices .......................................................................................................................24
7 Index of Key Words and Subjects in the Technical Bulletins.........................................................................27
8 References ....................................................................................................................................................29
8.1 References.............................................................................................................................................29
8.2 Useful Resources..................................................................................................................................30
NFIP TECHNICAL BULLETIN 0 JULY 2019 i
List of Figures
Figure 1: Typical flood zones from coastal and riverine flood sources......................................................15
Figure 2: Lowest floor reference point for Zone A (at top of lowest floor) versus Zone V
(at bottom of lowest horizontal structural member of lowest floor) ..........................................16
Figure 3: Locations of FEMA Headquarters and 10 FEMA Regional Offices...........................................25
List of Tables
Table 1: Technical Bulletin Synopses............................................................................................................2
Table 2: Crosswalk of NFIP Regulations, Technical Bulletins, and Key Concepts....................................8
Table 3: FEMA Headquarters and Regional Office Contact Information...............................................26
ii NFIP TECHNICAL BULLETIN 0 JULY 2019
Acronyms
ASCE American Society of Civil Engineers
BFE base flood elevation
CFR Code of Federal Regulations
DFE design flood elevation
DHS Department of Homeland Security
FEMA Federal Emergency Management Agency
FHBM Flood Hazard Boundary Map
FIMA Federal Insurance and Mitigation Administration
FIRM Flood Insurance Rate Map
FIS Flood Insurance Study
IBC International Building Code°
ICC International Code Council°
I-Codes International Codes°
IRC International Residential Code°
NFIP National Flood Insurance Program
SEI Structural Engineering Institute
SFHA Special Flood Hazard Area
TB Technical Bulletin
NFIP TECHNICAL BULLETIN 0 JULY 2019 iii
1 Introduction and Background
Beginning in the early 1990s, the Federal Insurance and Mitigation Administration of the Federal
Emergency Management Agency (FEMA) has issued 11 Technical Bulletins that provide guidance on
interpreting, enforcing, and complying with the minimum building performance requirements in the
National Flood Insurance Program (NFIP) regulations (Title 44 of the Code of Federal Regulations
[CFR] Parts 59 and 60). These requirements are intended to reduce the loss of life and property as well as
the economic and social hardships that can result from flooding.
The NFIP is a Federal program established by the National Flood Insurance Act of 1968, as amended
(42 U.S. Code §§ 4011 et seq.). The primary purposes of the Act are to:
• Better indemnify individuals for flood losses through insurance
• Reduce future flood damage through State and community floodplain management regulations
• Reduce Federal expenditures for disaster assistance and flood control
To participate in the NFIP, communities must adopt and enforce floodplain management regulations that
meet or exceed NFIP floodplain management requirements. Owners of property located in communities
that participate can purchase NFIP flood insurance as a protection against the financial impact of flood
losses.
NFIP REQUIREMENTS AND HIGHER REGULATORY STANDARDS
State and Local Requirements. State or local requirements that are more stringent than the minimum
requirements of the NFIP take precedence. The Technical Bulletins and other FEMA publications provide
guidance on the minimum requirements of the NFIP and describe best practices. Design professionals,
builders, and property owners should contact local officials to determine whether more restrictive
provisions apply to buildings or sites in question. All other applicable requirements of the State or local
building codes must also be met.
Substantial Improvement and Substantial Damage.As part of issuing permits, local officials must
review not only proposals for new construction but also for work on existing buildings to determine
whether the work constitutes Substantial Improvement or repair of Substantial Damage. If the work is
determined to constitute Substantial Improvement or repair of Substantial Damage, the buildings must
be brought into compliance with the NFIP requirements for new construction. Some communities modify
the definitions of Substantial Improvement and/or Substantial Damage to be more restrictive than the
NFIP minimum requirements. For more information on Substantial Improvement and Substantial Damage,
see FEMA P-758, Substantial Improvement/Substantial Damage Desk Reference (2010), and FEMA 213,
Answers to Questions About Substantially Improved/Substantially Damaged Buildings (2018).
Higher Building Elevation Requirements. Some communities require that buildings be elevated above
the NFIP minimum requirement. The additional elevation is called freeboard. Design professionals,
builders, and property owners should check with local officials to determine whether a community has
freeboard requirements. References to building elevations in this Technical Bulletin should be construed
as references to the community's elevation requirement in areas where freeboard is required.
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NFIP TECHNICAL BULLETIN 0 JULY 2019 1
The NFIP floodplain management regulations, contained in 44 CFR § 60.3, include minimum building
performance criteria that apply to (1) new construction, (2) work determined to be Substantial
Improvement such as improvements,alterations,and additions,and (3) the repair of buildings determined
to have incurred Substantial Damage and that are in Special Flood Hazard Areas (SFHAs).
1.1 Intended Audience
The Technical Bulletins are intended for use primarily by State and local officials who are responsible for
interpreting and enforcing the NFIP floodplain management regulations.
The Technical Bulletins may also be used by design professionals (e.g.,architects, engineers), contractors,
building owners and operators,planners,and other interested stakeholders to help understand and comply
with NFIP floodplain management requirements. Using the information in the Technical Bulletins will
improve the design and construction of buildings, including their utility systems, that are in floodprone
areas, thereby reducing the potential for damage and increasing building and community resilience.
1.2 Purpose of Technical Bulletins TECHNICAL BULLETINS
The Technical Bulletins provide specific FEMA guidance AND FLOODPLAIN MANAGEMENT
for State and local floodplain management officials BULLETINS
on complying with the NFIP's minimum floodplain The NFIP Technical Bulletins provide
management criteria. While the primary focus of the guidance on complying with the
Technical Bulletins is on how to meet the minimum NFIP minimum NFIP floodplain management
floodplain management requirements, they also include requirements that apply to buildings.
information on: FEMA's Floodplain Management Bulletins
provide guidance on administering
• Recommended best practices for reducing flood losses the NFIP requirements that apply to
• Considerations related to NFIP flood insurance rates development other than buildings and
guidance on some building requirements.
• Building codes and standards The Floodplain Management Bulletins
Additional information on how to use the Technical are available at https://www.fema.gov/
Bulletins is provided in Section 2. floodplain-management-publications.
1.3 Synopses of Technical Bulletins (as of June 2019)
Table 1: Technical Bulletin Synopses
0 User's Guide to Technical Bulletins Introduction and background for the TBs, including the intended
(2019) audience, purpose, and synopses of available TBs; how to use the
TBs; crosswalk of NFIP regulations and the TBs; key concepts and
requirements used in the TBs; key terms and useful resources;
supplemental information, including how to obtain copies of the
TBs; FEMA Headquarters and Regional Office locations; and a key
word/subject index for the TBs.
2 NFIP TECHNICAL BULLETIN 0 JULY 2019
Table 1: Technical Bulletin Synopses(concluded)
= Title D.
1 Openings in Foundation Walls and Guidance on the NFIP requirements for openings on exterior walls
Walls of Enclosures Below Elevated and walls of enclosures below elevated buildings in Zones A, AE,
Buildings in Special Flood Hazard Al—A30,AR, AO, and AH.
Areas (2008)
2 Flood Damage-Resistant Materials Guidance on the NFIP requirements on the use of flood damage-
Requirements for Buildings Located resistant construction materials in building components below the
in Special Flood Hazard Areas(2008) BFE in SFHAs(both Zones A and V).
3 Non-Residential Floodproofing— Guidance on the NFIP requirements concerning substantially
Requirements and Certification for impermeable construction and the required certification for dry
Buildings Located in Special Flood floodproofed non-residential buildings with lowest floors below the
Hazard Areas(1993) BFE in Zones A, AE, Al—A30, AR, AO, and AH.
4 Elevator Installation for Buildings Guidance on the NFIP requirements for elevator machinery and
Located in Special Flood Hazard equipment that serve buildings and on the installation of elevators
Areas (2019) below the BFE in SFHAs(both Zones A and V).
5 Free-of-Obstruction Requirements Guidance on NFIP requirements concerning obstructions to
for Buildings Located in Coastal High floodwaters beneath elevated buildings and on building sites in
Hazard Areas(2008) Coastal High Hazard Areas(Zones V, VE, and V1-V30).
6 Below-Grade Parking Requirements Guidance on the NFIP requirements for below-grade parking ga-
for Buildings Located in Special rages beneath non-residential buildings located in Zones A, AE,
Flood Hazard Areas(1993) Al—A30,AR, AO, and AH.
7 Wet Floodproofing Requirements for Guidance on the NFIP requirements concerning measures referred
Structures Located in Special Flood to as "wet floodproofing" applied to certain types of structures in
Hazard Areas(1993) Zones A, AE,Al—A30, AR,AO, and AH.
8 Corrosion Protection for Metal Why maintaining the load paths in buildings is important and
Connectors and Fasteners in Coastal the important role that the proper corrosion protection of metal
Areas (2019) connectors and fasteners has in ensuring that buildings in coastal
areas are adequately anchored and connected to resist floods and
high wind events.
9 Design and Construction Guidance Prescriptive, simplified, and performance-based design
for Breakaway Walls Below Elevated approaches to meeting NFIP requirements in the design and
Buildings Located in Coastal High construction of wood-framed breakaway walls beneath elevated
Hazard Areas(2008) buildings in Coastal High Hazard Areas(Zones V,VE, and V1 30).
10 Ensuring That Structures Built on Regulatory and technical guidance on ensuring that the
Fill In or Near Special Flood Hazard construction of the following buildings are reasonably safe from
Areas Are Reasonably Safe From flooding: buildings with various types of foundations, including
Flooding(2001) basements, in areas that have been proposed to be removed from
the SFHA through the placement of fill and in areas near the SFHA.
11 Crawlspace Construction for Interim guidance on minimum NAP requirements and best
Buildings Located in Special Flood practices for crawlspace construction, including requirements for
Hazard Areas(2001) below-grade crawlspace construction that may extend 1 or 2 feet
below grade.
BFE=base flood elevation
FEMA=Federal Emergency Management Agency
NFIP=National Flood Insurance Program
SFHA=Special Flood Hazard Area
TB=Technical Bulletin
NFIP TECHNICAL BULLETIN 0 JULY 2019 3
1.4 Organization of Technical Bulletin 0 — User's Guide
to Technical Bulletins
This User's Guide to Technical Bulletins contains:
• Information on how to use the Technical Bulletins
• Crosswalk of the NFIP regulations and the Technical Bulletins
• Key concepts and requirements in the Technical Bulletins
• Glossary of acronyms and key terms
• How to obtain copies of Technical Bulletins and submit comments
• FEMA Headquarters and Regional office contact information
• Index of key words and subjects in the Technical Bulletins
• References and resources
2 How to Use the Technical Bulletins
FEMA revises or develops new Technical Bulletins as needed to provide guidance to State and local
officials, design professionals, contractors, building owners and operators, planners, and other interested
stakeholders to help them comply with NFIP floodplain management requirements.
The Technical Bulletins are focused on minimum NFIP floodplain management criteria. They also
provide guidance on best practices for floodplain management and flood hazard-resistant construction,
building codes and standards, and NFIP flood insurance considerations.
2.1 Minimum NFIP Floodplain
Management Criteria MINIMUM FLOODPLAIN
To participate in the NFIP,communities must adopt MANAGEMENT CRITERIA
regulations that meet or exceed the minimum The guidance in the Technical Bulletins
requirements in 44 CFR § 60.3. The Technical represents established, application
Bulletins provide specific FEMA guidance on methodologies for, minimum NFIP floodplain
complying with minimum NFIP floodplain management criteria.
management requirements.If a community chooses
not to use the methods or implement the measures
that are described in the Technical Bulletins, the REASONABLY SAFE FROM FLOODING
community must demonstrate how it is meeting the The Technical Bulletins can be used by
requirements of 44 CFR§ 60.3. communities to help them evaluate whether
In addition to the community's responsibility to proposed development will be reasonably safe
ensure specific building requirements are met, from flooding.
such as elevating or dry floodproofing buildings,
4 NFIP TECHNICAL BULLETIN 0 JULY 2019
elevating or otherwise protecting utilities, and installing openings in enclosure walls, communities are
also required to review development proposals "to determine whether such proposals will be reasonably
safe from flooding" (44 CFR§ 60.3(a)(4)).
To participate in the NFIP, all communities must adopt
a resolution or ordinance that expresses a "commitment
to recognize and evaluate flood hazards in all official COMMUNITY COMMITMENT
actions and to take such other official action as reasonably TO REDUCING FLOOD LOSSES
necessary to carry out the objectives of the program" (44 CFR Using the guidance in the Technical
§ 59.22(a)(8)). This is in addition to the general requirement Bulletins illustrates a community's
that communities "take into account flood hazards to the commitment toward evaluating and
extent that they are known in all official actions relating to addressing flood hazards.
land management and use" (44 CFR§ 60.1(c)).
2.2 Best Practices
Some of the best practices for floodplain management and
flood hazard-resistant construction that are described in
the Technical Bulletins are recommendations for increasing USE OF SHALL OR MUST
hazard resistance in buildings and their utility systems and for "Shall" or "must" in the Technical
reducing the loss of life and property and economic and social Bulletins indicates official guidance
hardships. on methods or measures required
FEMA strongly encourages that these best practices be: for compliance with 44 CFR
§ 60.3. Other measures, such
• Incorporated into State or community floodplain as best practices, do not have
management ordinances or building codes "shall" or"must." FEMA strongly
encourages that these measures
• Implemented by designers, builders, or other stakeholders en en considered.
to reduce risk and improve resilience
• Used to potentially lower NFIP flood insurance premiums
Many of these best practices are based on field-verified data including data from decades of post-disaster
building performance assessments.
EXAMPLE OF A BEST PRACTICE FROM TECHNICAL BULLETIN 2,
FLOOD DAMAGE-RESISTANT MATERIALS REQUIREMENTS
If the lowest floor of a building is elevated higher than the BFE, which is common when the owner wants a
full story of elevation to accommodate parking under the building, FEMA recommends that flood damage-
resistant materials also be used up to the level of the lowest floor to reduce damage in these areas should
flooding exceed the BFE.
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NFIP TECHNICAL BULLETIN 0 JULY 2019 5
2.3 Building Codes and Standards
In addition to complying with the NFIP requirements, all
new construction, Substantial Improvements, and repair BUILDING CODES
of Substantial Damage must comply with the applicable AND STANDARDS COMPARISON
building codes and standards that have been adopted and WITH NFIP REQUIREMENTS
that are enforced by States and communities. Building codes Each Technical Bulletin provides a
govern the design, construction, alteration, and maintenance comparison of the building codes
of structures. They specify the minimum requirements and standards that are related
to adequately safeguard the health, safety, and welfare of to the Technical Bulletin's topic
building occupants. Rather than create and maintain their and the NFIP requirements. The
own building codes, most States and local jurisdictions adopt comparison indicates the aspects
the International Codes° (I-Codes°), which are a family of of the codes/standards and
model building codes published by the International Code the NFIP requirements that are
Council° (ICC°). equivalent and the aspects of the
codes/standards that exceed the
I-Codes include the International Residential Code° NFIP requirements.
(IRC®), International Building Code° (IBC°), International
Existing Building Code° (IEBC®), and codes that govern the
installation of mechanical, plumbing, fuel gas service, and BUILDING CODE ADOPTION
other aspects of building construction. Provisions in State- AND ENFORCEMENT
and community-adopted building codes can vary from these
model codes, so coordination with local building officials is Building codes are only
necessary to confirm which requirements apply within a given enforceable if adopted by the State
jurisdiction. or community but can serve as
best practices in communities that
The IBC applies to all applicable buildings and structures have not adopted codes.
whereas the scope of the IRC is limited to one-and two-family
dwellings and townhomes not more than three stories above
grade plane. The IBC can be used to design dwellings,but it is used primarily for buildings and structures
other than dwellings within the IRC scope. The flood provisions in the IBC are included by reference to
ASCE 24, Flood Resistant Design and Construction, a standard developed by the American Society of Civil
Engineers (ASCE).
FEMA has deemed that the latest published editions of the I-Codes meet or exceed NFIP requirements
for buildings and structures. Excerpts of the flood provisions of the I-Codes are available on FEMA's
Building Code Resource webpage (http://www.fema.gov/building-code-resources).
The joint ICC and FEMA publication Reducing Flood Losses Through the International Codes: Coordinating
Building Codes and Floodplain Management Regulations, 4th Edition (2014) recommends that communities
coordinate the administration of floodplain management provisions and building codes. Differences in
requirements between the regulatory tools can lead to inconsistencies or confusion when administering
and enforcing requirements for development in floodprone areas.
6 NFIP TECHNICAL BULLETIN 0 JULY 2019
2.4 NFIP Flood Insurance Considerations
Each Technical Bulletin addresses NFIP flood insurance considerations related to the topic of the
Technical Bulletin. The following stakeholders should be aware of these considerations:
• Local officials, designers, builders, and other stakeholders
• Property owners who are concerned about the impact of design and construction decisions on their
NFIP flood insurance premiums
NFIP flood insurance premiums are based on factors that include,
but are not limited to, flood risk zone, elevation of the lowest floor NFIP FLOOD INSURANCE
above or below the BFE, type of building and foundation, the
The Technical Bulletins
number of floors, and whether there is a basement or enclosure
describe how NFIP flood
below the elevated building.
insurance premiums can be
The Technical Bulletins address situations in which a compliant affected by changes in design
building might still be subject to higher NFIP flood insurance and construction. For example,
premiums. As only one example, Technical Bulletin 3, Non- some best practices can
Residential Floodproofang—Requirements and Certification for Buildings significantly lower annual NFIP
Located in Special Flood Hazard Areas, notes that the minimum flood insurance premiums.
NFIP requirements allow a new or Substantially Improved non-
residential building in Zone A to have a lowest floor below the BFE,
provided that the building has been designed, constructed, and certified to be floodproofed and meets
established criteria. However, while the building needs to be protected only to the BFE for floodplain
management purposes, freeboard is considered for NFIP flood insurance rating purposes. Because of
the additional risk associated with any floodproofed building, for NFIP flood insurance rating, I foot is
subtracted from the elevation to which a building has been floodproofed. Therefore, to receive an NFIP
insurance rating based on the BFE, the building must be floodproofed to an elevation of at least I foot
above the BFE.
3 Crosswalk of NFIP Regulations
and Technical Bulletins
Table 2 is a crosswalk of select NFIP regulations and the Technical Bulletins that provide guidance on
them. The table is intended to be a general guide to the Technical Bulletins; it does not include all of
the NFIP regulations. See the index in Section 7 for more information on where to find guidance in the
Technical Bulletins on specific NFIP regulations.
NFIP TECHNICAL BULLETIN 0 JULY 2019 7
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4 Key Concepts and Requirements
for Structures
Users of the Technical Bulletins should have a basic understanding of the following key concepts:
• Special Flood Hazard Areas (SFHAs)
• Lowest floor, enclosure, and basement
• Substantial Improvement and Substantial Damage
• Open foundations in Zone V
These concepts underlie the requirements that are critical in determining compliance with minimum
NFIP floodplain management criteria. Most of these concepts and other key terms used in NFIP
regulations are defined in Sections 4 and 5.
4.1 Special Flood Hazard Areas
The SFHA is the land area in the floodplain subject to flooding by the base flood. SFHAs are shown on
FIRMs prepared by FEMA as Zones A and V. The base flood is the flood that has a 1 percent chance of
being equaled or exceeded in any given year (commonly called the "100 year flood"). FIRMs also show
Zone X,which are areas outside the SFHA.
In communities that participate in the NFIP, the minimum
floodplain management requirements govern development in NFIP DEFINITION OF
SFHAs, including buildings and other structures, subdivisions, DEVELOPMENT
new and replacement water supply systems, and new and
Any man-made change to
replacement sanitary sewage systems. Floodplain management improved or unimproved real
requirements for buildings and other structures can differ estate, including but not limited
depending on the flood zone in which a structure is located. to buildings or other structures,
Figure 1 shows the typical flood zones from coastal and riverine mining, dredging, filling, grading,
flood sources. The criteria for construction in Zones V,VE, and paving, excavation or drilling
Vl V30, which are collectively referred to as Zone V or Coastal operations, or storage of
equipment or materials" (44 CFRquip
High Hazard Areas, are generally more stringent than in Zones e uip
A,AE,Al—A30,AR,AO,and AH,which are collectively referred
to as Zone A. Zone A exists in both coastal and riverine flood
source environments.
Zone A. In SFHAs identified as Zone A (Zones A,AE,Al—A30,AR,AO, and AH), the principal source of
flooding is runoff from rainfall, snowmelt, or coastal storms when the potential base flood wave height
is less than 3.0 feet. Zone A has minimum requirements that specify the elevation of the lowest floor,
including the basement, in relation to the BFE or depth of the base flood. Specific requirements apply to
fully enclosed areas below the lowest floor.
14 NFIP TECHNICAL BULLETIN 0 JULY 2019
COASTAL
F I F-1 F] F-1
El
(Shaded and Unshaded)--/4(A,AE,AI-30,AH,AO,AR,A99) (V,VE,VI-30)
Wave Wave height Wave height>_3 feet
Floodway Limit of base height 1.5-3.0 feet
•H• flooding and <1.5 feet
waves 1-percent-annual- Flood level including wave effects
chance flood elevation
____ —� 100-year Stillwater elevation
• Base flood —
! elevation Sea level
r
Limit of Moderate
Wave Action Shoreline
Figure 1: Typical flood zones from coastal and riverine flood sources
Zone V. Zone V (Zones V, VE, and Vl V30),
COASTAL A ZONE also called Coastal High Hazard Areas, extends
Since 2009, coastal flood studies have examined from offshore to the inland limit of a primary
wave conditions in Zone A. Based on the studies, frontal dune along an open coast, and any other
FEMA delineates an informational line called the area subject to high-velocity wave action from
Limit of Moderate Wave Action (LiMWA) on FIRMs storms or tsunamis where the potential base
where wave heights in Zone A are expected to be flood wave height is 3.0 feet or more. Zone V has
1.5 feet or greater during base flood conditions. minimum requirements pertaining to the siting
See Figure 1. of buildings, elevation of the lowest horizontal
FEMA uses the term "Coastal A Zone" to refer structural member of the lowest floor in relation
to areas seaward of the LiMWA and landward of to the BFE, foundation design, enclosures below
the Zone V boundary or landward of the shoreline the lowest floor, and alterations of sand dunes
where Zone V is not identified. The term refers and mangrove stands.
to some areas identified as Zone A that are Zone X. Zone X identifies areas outside the
subject to flooding from a coastal or tidal source. SFHA. Zone X (shaded) identifies two areas
However, Coastal A Zones are not identified on of moderate flood hazard: (1) areas subject to
FIRMs, and the NFIP regulations for development inundation by the flood that has a 0.2 percent
in SFHAs and the NFIP regulations that govern
the identification of SFHAs on maps do not use chance of being equaled or exceeded during
any given year (commonly called the "500-year
the term "Coastal A Zone."
flood") and (2) areas protected by accredited
The NFIP floodplain management requirements levee systems. Zone X (unshaded) identifies
regulate areas identified as Coastal A Zones to areas of minimal flood hazard,which are outside
Zone A standards. FEMA's Community Rating the 500-year floodplain. The NFIP floodplain
System awards credits to communities that management requirements do not apply in
regulate Coastal A Zones to Zone V standards.
Zone X.
The latest editions of the I-Codes and ASCE 24
require buildings in Coastal A Zones to meet Example of Criteria Difference. An example
Zone V requirements; FEMA guidance, best of a difference in criteria for Zone A and Zone
practices, and FEMA Mitigation Assessment V is where the lowest floor is measured (see
Team reports support this requirement. Figure 2):
----------------------------------------------------------------------------------------
NFIP TECHNICAL BULLETIN 0 JULY 2019 15
• In Zone A, the lowest floor (including basement) of a structure must be elevated to or above the BFE.
• In Zone V, the bottom of the lowest horizontal structural member of the lowest floor of a structure
(excluding pilings or columns) must be elevated to or above the BFE.
Figure 2:
Lowest floor reference point for
Reference for Zone A(at top of lowest floor)
structural elevation versus Zone V(at bottom of lowest
Floor framing horizontal structural member of
lowest floor)
Floor framing Base flood elevation
Lowest horizontal
structural member
supporting floor
Foundation
element
4.2 Lowest Floor, Enclosure, and Basement
Under the NFIP:
• The lowest floor is defined as "the lowest floor of the lowest enclosed area (including basement).An
unfinished or flood resistant enclosure, usable solely for parking of vehicles, building access or storage
in an area other than a basement area is not considered a building's lowest floor; Provided, that such
enclosure is not built so as to render the structure in violation of the applicable non-elevation design
requirements of§ 60.3" (44 CFR§ 59.1).
• An enclosure is an area below the lowest floor that is enclosed on all sides by walls.
• A basement is defined as "any area of the building having its floor subgrade (below ground level) on
all sides" (44 CFR§ 59.1).
4.3 Substantial Improvement and Substantial Damage
The repair or improvement of buildings presents an opportunity to reduce future flood damage to the
structures and to improve their resilience. Local floodplain management regulations based on the NFIP
and building codes contain requirements that apply not only to new structures but also to buildings with
proposed Substantial Improvements or repair of Substantial Damage (described below).
As part of issuing permits, local officials must review not only proposals for new construction but also for
work on existing buildings to determine whether the work constitutes Substantial Improvement or repair
of Substantial Damage. If the work is determined to constitute Substantial Improvement or repair of
Substantial Damage, the buildings must be brought into compliance with the NFIP requirements for new
construction, including the requirement that the lowest floor be elevated to or above the BFE. Meeting
this requirement can also be accomplished by demolishing the building followed by constructing a new
building that meets the NFIP requirements on the same site or by relocating the building to outside the
SFHA. More information on Substantial Improvement and Substantial Damage can be found in FEMA
16 NFIP TECHNICAL BULLETIN 0 JULY 2019
P-758, Substantial Improvement/Substantial Damage Desk Reference(2010), and FEMA 213, Answers to Questions
About Substantially Improved/Substantially Damaged Buildings (2018).
Substantial Improvement is defined in 44 CFR§ 59.1 as:
... Any reconstruction, rehabilitation, addition, or other improvement of a structure, the cost
of which equals or exceeds 50 percent of the market value of the structure before the "start
of construction" of the improvement. This term includes structures which have incurred
"substantial damage," regardless of the actual repair work performed. The term does not,
however, include either:
(1) Any project for improvement of a structure to correct existing violations of state or local
health, sanitary, or safety code specifications which have been identified by the local code
enforcement official and which are the minimum necessary to assure safe living conditions
or
(2)Any alteration of a "historic structure," provided that the alteration will not preclude the
structure's designation as a"historic structure."
Substantial Damage is defined in 44 CFR§59.1 as"damage of any origin sustained by a structure whereby
the cost of restoring the structure to its before-damaged condition would equal or exceed 50 percent of
the market value of the structure before the damage occurred." Substantial Damage can have any cause,
not just flooding.
Some communities modify the definitions of Substantial Improvement and Substantial Damage
requirements in one of two ways: (1) adopting a lower threshold than 50 percent (e.g., 40 percent, 30
percent) or (2) tracking costs of improvements and costs of repairs over a specific period, referred to as
"cumulative Substantial Improvement."
4.4 Open Foundations in Zone V
Coastal waves and flooding can exert strong hydrodynamic COASTAL A ZONE
forces on any building element that is exposed to waves or the WAVE HAZARD
flow of water. Therefore, open foundation systems that offer
minimal resistance to waves and floodwaters passing beneath Coastal Zones are subject
elevated buildings (e.g., pile and column foundations) are conditionn s similar to those in Zone
V(Coastal High Hazard Areas),
required in Zone V. including breaking waves, erosion,
The NFIP requires that all new construction and Substantially and scour.
Improved buildings in Zone V be elevated to or above the BFE Although the minimum NFIP
on open foundations (pilings, columns, and sometimes shear requirements for Coastal A Zones
walls) that allow floodwater and waves to pass beneath the are the same as Zone A, it is
elevated structure. The NFIP further requires that areas below recommended that structures in
elevated structures remain free of obstructions that would Coastal A Zones be designed and
prevent the free flow of coastal floodwater and waves during a constructed to Zone V standards.
base flood event.
NFIP TECHNICAL BULLETIN 0 JULY 2019 17
5 Acronyms and Key Terms
The acronyms and key terms that are used in the Technical Bulletins are defined in Sections 5.1 and 5.2,
respectively.
5.1 Acronyms Used in the Technical Bulletins
ACI American Concrete Institute IRC International Residential Code
ADA Americans with Disabilities Act LAG lowest adjacent grade
AF&PA American Forest&Paper Association LHSM lowest horizontal structural member
ANSI American National Standards LiMWA Limit of Moderate Wave Action
Institute LOMC Letter of Map Change
ASCE American Society of Civil Engineers LOMR F Letter of Map Revision based on fill
ASME American Society of Mechanical MAT Mitigation Assessment Team
Engineers MRL machine room-less traction elevators
ASTM American Society for Testing and MSJC Masonry Standard Joint Committee
Materials
AWC American Wood Council NDS National Design Specification
BFE base flood elevation NEMA National Emergency Management
Agency; National Electrical
CAZ Coastal A Zone Manufacturers Association
CCA chromated copper arsenate NFIP National Flood Insurance Program
CFR Code of Federal Regulations NFPA National Fire Protection Association
CMU concrete masonry unit NGVD National Geodetic Vertical Datum
DFE design flood elevation oz/112 ounces per square foot
EIFS Exterior Insulation Finishing System PFD primary frontal dune
FEMA Federal Emergency Management PWF Permanent Wood Foundation
Agency SBX/DOT sodium borate disodium octaborate
FHBM Flood Hazard Boundary Map tetrahydrate
FIA Federal Insurance Administration SEI Structural Engineering Institute
FIMA Federal Insurance and Mitigation SFHA Special Flood Hazard Area
Administration
SFIP Standard Flood Insurance Policy
FIRM Flood Insurance Rate Map
SSPC Society for Protective Coatings
FIS Flood Insurance Study TB Technical Bulletin
IBC International Building Code TPI Truss Plate Institute
ICC International Code Council
USACE U.S.Army Corps of Engineers
ICC-ES ICC Evaluation Service
VPL vertical platform lift
I-Codes International Codes
WTCA Wood Truss Council of America
IEBC International Existing Building Code
IMOA International Molybdenum
Association
18 NFIP TECHNICAL BULLETIN 0 JULY 2019
5.2 Glossary of Terms Used
in Technical Bulletins DEFINITIONS OF TERMS
Readers are cautioned that the
The quoted material from ASCE 24-14 in this glossary is used definitions of some of the terms
with permission. that are used in the Technical
Accessory (or appurtenant) structure. "Structure which is on Bulletins are not the same when
used by the NFIP for the purpose
the same parcel of property as the principal structure to of rating flood insurance policies.
be insured and the use of which is incidental to the use of Definitions specific to NFIP
the principal structure" (44 CFR§ 59.1). Detached garages flood insurance can be found in
used for parking of vehicles and limited storage and small FEMNs Flood Insurance Manual.
sheds used for limited storage are considered accessory
structures.
Area of special flood hazard. "Land in the flood plain within a community subject to a 1 percent or
greater chance of flooding in any given year. The area may be designated as Zone A on the Flood
Hazard Boundary Map (FHBM). After detailed ratemaking has been completed in preparation for
publication of the flood insurance rate map, Zone A usually is refined into Zones A,AO,AH,Al-30,
AE, A99,AR, AR/A1-30, AR/AE, AR/AO, AR/AH, AR/A, VO, or VI 30, VE, or V. For purposes of
these regulations, the term `special flood hazard area' is synonymous in meaning with the phrase
,area of special flood hazard' " (44 CFR§ 59.1).
Base flood. "Flood having a one percent chance of being equaled or exceeded in any given year" (44 CFR
§ 59.1).
Base flood elevation (BFE). The computed elevation to which floodwater is anticipated to rise during
the base flood, including wave height, relative to the datum specified on the Flood Insurance Rate
Map. The BFE is shown on the FIRM for Zones AE,AH,Al—A30, AR,AR/A,AR/AE,AR/Al—A30,
Vl V30, and VE. For Zones AR/AH and AR/AO, a depth of flooding is provided for the 1 percent
annual chance event. SFHAs without BFEs are identified on FIRMs as Zone A or Zone V. When
BFEs are not identified, communities must obtain, review and reasonably use any BFE data available
from a Federal, State, or other source.
Basement. "Area of the building having its floor subgrade (below ground level) on all sides" (44 CFR
§59.1).NFIP regulations do not allow basements to extend below the BFE except in dry-floodproofed,
non-residential buildings.
Breakaway wall. "A wall that is not part of the structural support of the building and is intended through
its design and construction to collapse under specific lateral loading forces without causing damage
to the elevated portion of the building or supporting foundation system" (44 CFR§ 59.1)
Coastal A Zone. "Area within a special flood hazard area, landward of a V Zone or landward of an open
coast without mapped V Zones. In a Coastal A Zone, the principal source of flooding must be
astronomical tides, storm surges, seiches, or tsunamis, not riverine flooding. During the base flood
conditions, the potential for breaking wave heights shall be greater than or equal to 1.5 feet. The
inland limit of the Coastal A Zone is (1) the Limit of Moderate Wave Action if delineated on a FIRM, or
(2) designated by the authority having jurisdiction"(ASCE 24-14).
NFIP TECHNICAL BULLETIN 0 JULY 2019 19
Coastal High Hazard Area. "An area of special flood hazard extending from offshore to the inland limit
of a primary frontal dune along an open coast and any other area subject to high velocity wave
action from storms or seismic sources" (44 CFR§ 59.1). The coastal high hazard area is shown on a
FIRM or other flood hazard map as Zone V,VO,VE, or V1 V30.
Community. "Any State or area or political subdivision thereof, or any Indian tribe or authorized tribal
organization, or Alaska Native village or authorized native organization, which has authority
to adopt and enforce floodplain management regulations for the areas within its jurisdiction"
(44 CFR§ 59.1).
Design flood. "The flood associated with the greater of the following two areas: (1) area within a floodplain
subject to a 1% or greater chance of flooding in any year, or (2) area designated as a flood hazard area
on a community's flood hazard map or otherwise legally designated" (ASCE 24-14).
Design flood elevation (DFE). "Elevation of the design flood, including wave height, relative to the datum
specified on the community's flood hazard map" (ASCE 24-14). In areas designated as Zone AO, the
design flood elevation is the elevation of the highest existing grade of the building's perimeter plus
the depth number (in feet) specified on the flood hazard map. In areas designated as Zone AO
where a depth is not specified on the map, the depth is taken as equal to 2 feet. The DFE is the
locally adopted regulatory flood elevation. If a community regulates based on the FIRM, the DFE is
identical to the BFE. If a community chooses to regulate based on a different flood hazard map, a
lower frequency flood, or adds freeboard, the DFE must be at least as high as the BFE.
Detailing. Design practice of using structural and architectural drawings and specifications to arrange,
configure, and connect structural and nonstructural building components of a building system.
Design details convey to the contractor exactly how the structural and nonstructural components of
a building should be built.
Development. 'Any man-made change to improved or unimproved real estate, including but not limited
to buildings or other structures, mining, dredging, filling, grading, paving, excavation or drilling
operations or storage of equipment or materials" (44 CFR§ 59.1).
Elevation Certificate. An NFIP administrative tool used to document elevation and other information
necessary to determine compliance with a community's floodplain management requirements,
determine proper insurance premium rates, or support requests for Letters of Map Change
(LOMCs).
Enclosure or enclosed area. Area below an elevated building and enclosed by walls on all sides. The
NFIP does not explicitly define "enclosure," but it is mentioned in the definition of "lowest floor."
Enclosures may be formed by foundation perimeter walls (crawlspace), framed walls, or breakaway
walls. Also defined in ASCE 24-14 as the "confined area below the DFE, formed by walls on all sides
of the enclosed space."
Existing construction (may also be referred to as existing construction/structures). For the purposes
of determining flood insurance rates, structures for which the "start of construction" commenced
before the effective date of the FIRM or before January 1, 1975, for FIRMS effective before that
date. "Existing construction" may also be referred to as "existing structures" (44 CFR § 59.1).
Also defined in ASCE 24-14 as "any structure for which the start of construction commenced before
the effective date of the first floodplain management code, ordinance, or standard adopted by the
authority having jurisdiction."
20 NFIP TECHNICAL BULLETIN 0 JULY 2019
Flood Hazard Boundary Map (FHBM). "Official map of a community, issued by the Federal Insurance
Administrator, where the boundaries of the flood, mudslide (i.e., mudflow) related erosion areas
having special hazards have been designated as Zones A, M and/or E" (44 CFR§ 59.1).
Flood Insurance Rate Map (FIRM). "Official map of a community, on which ... [FEMA] has delineated
both the special hazard areas and the risk premium zones applicable to the community"
(44 CFR§ 59.1).
Flood Insurance Study (FIS) (flood elevation study). "An examination, evaluation and determination
of flood hazards and, if appropriate, corresponding water surface elevations, or an examination,
evaluation and determination of mudslide (i.e., mudflow) and/or flood-related erosion hazards"
(44 CFR§ 59.1). The FIS is the official report provided by FEMA that contains the FIRM, the Flood
Boundary and Floodway Map (if applicable), the water surface elevations of the base flood, and
supporting technical data.
Floodplain or floodprone area. "Any land area susceptible to being inundated by water from any source"
(44 CFR§ 59.1).
Floodproofing,dry. "Any combination of structural and non-structural additions,changes,or adjustments
to structures which reduce or eliminate flood damage to real estate or improved real property,water
and sanitary facilities, structures and their contents" (44 CFR § 59.1). Referred to simply as "flood
proofing" in 44 CFR § 59.1. Further defined in ASCE 24-14 as "a combination of measures that
results in a structure,including the attendant utilities and equipment,being water tight,with all elements
substantially impermeable and with structural components having the capacity to resist flood loads."
Floodproofing, wet. `Floodproofing method that relies on the use of flood damage-resistant materials
and construction techniques in areas of a structure that are below the elevation required by this
standard by intentionally allowing those areas to flood" (ASCE 24-14). The NFIP does not define
wet floodproofing. Wet floodproofing measures allow areas to flood in such a way that damage
to a structure and its contents is minimized by using specific design, construction, and planning
measures outlined in Technical Bulletin 7, Wet Floodproofing Requirements for Structures Located in
Special Flood Hazard Areas.
Floodproofing Certificate. An NFIP administrative tool that documents certification by a registered
professional engineer or architect that the design and methods of construction of a nonresidential
building are in accordance with accepted practices for meeting a community's floodplain
management requirements for floodproofing. This documentation is required for both floodplain
management requirements and NFIP flood insurance rating purposes.
Flow diversion. Change in the course of flood flow when it encounters an object or structure. Diversion
can be accompanied by an increase in the local flood level and/or flood velocity when the blockage
is large relative to the area through which the flow would otherwise pass.
Hydrodynamic loads. "Loads imposed on an object [such as a building or foundation element] by water
flowing against and around it" (ASCE 24-14). Examples are positive frontal pressure against the
structure,drag effect along the sides,and negative pressure on the downstream side.The magnitude
of hydrodynamic load varies as a function of the square of velocity and other factors.
NFIP TECHNICAL BULLETIN 0 JULY 2019 21
Hydrostatic loads. "Loads imposed on an object [or a surface, such as a wall or floor slab] by a standing
mass of water" (ASCE 24-14). Hydrostatic loads can be caused by slowly moving masses of water.
Hydrostatic load increases as water depth increases.
Limit of Moderate Wave Action (LiMWA). "The inland limit of the area affected by [breaking] waves
greater than 1.5 feet" (FEMA Procedure Memorandum No. 50). FEMA began delineating the
LiMWA on coastal FIRMS in 2009.
Lowest floor. Lowest floor of the lowest enclosed area of a building, including basement.An unfinished or
flood-resistant enclosure that is used solely for parking of vehicles, building access, or storage in an
area other than a basement area is not considered a building's lowest floor, provided the enclosure is
built in compliance with applicable requirements.
Net open area. Permanently open area of a non-engineered flood opening.
New construction (may also be referred to as new construction/structures). "... For floodplain
management purposes, new construction means structures for which the start of construction
commenced on or after the effective date of a floodplain management regulation adopted by a
community and includes any subsequent improvements to such structures" (44 CFR§ 59.1). Further
defined in ASCE 24-14 as "structures for which the start of construction commenced on or after the
effective date of the first floodplain management code, regulation, ordinance, or standard adopted
by the authority having jurisdiction, including any subsequent improvements to such structures. New
construction includes work determined to be substantial improvement."
Opening, engineered. Opening used to meet the requirement in 44 CFR§ 60.3(c)(5) that is "certified by
a registered professional engineer or architect" for meeting the requirement in 44 CFR§ 60.3(c)(5)
to "be designed to automatically equalize hydrostatic flood forces on exterior walls by allowing for
the entry and exit of floodwaters."
Opening, non-engineered. Opening used to meet the prescriptive requirement in 44 CFR § 60.3(c)(5)
to provide "a total net area of not less than one square inch for every square foot of enclosed area
subject to flooding."
Primary frontal dune. "A continuous or nearly continuous mound or ridge of sand with relatively steep
seaward and landward slopes immediately landward and adjacent to the beach and subject to
erosion and overtopping from high tides and waves during major coastal storms. The inland limit of
the primary frontal dune occurs at the point where there is a distinct change from a relatively steep
slope to a relatively mild slope" (44 CFR§ 59.1).
Registered design professional. Individual who is registered or licensed to practice his or her design
profession (e.g., architect, engineer, land surveyor) as defined by the statutory requirements of the
professional registration laws of the State or jurisdiction in which a project is to be constructed.
Special Flood Hazard Area (SFHA). Referred to as "area of special flood hazard." "Land in the flood
plain within a community subject to a 1 percent or greater chance of flooding in any given year. The
area may be designated as Zone A on the FHBM. After detailed ratemaking has been completed in
preparation for publication of the flood insurance rate map, Zone A usually is refined into Zones A,
AO, AH, Al-30, AE, A99, AR, AR/A1-30, AR/AE, AR/AO, AR/AH, AR/A, VO, or V1-30, VE, or V.
For purposes of these regulations, the term `special flood hazard area' is synonymous in meaning
with the phrase `area of special flood hazard"' (44 CFR§ 59.1).
22 NFIP TECHNICAL BULLETIN 0 JULY 2019
Standard residential garage door.A door, typically up to 18 feet wide by up to 8 feet tall, intended for use
in a residential garage for vehicular access and normally expected to be operated less than 1,500
cycles per year.
Structure. For floodplain management purposes, "a walled and roofed building, including a gas or liquid
storage tank, that is principally above ground, as well as a manufactured home" (44 CFR§ 59.1).
Substantial Damage. "Damage of any origin sustained by a structure whereby the cost of restoring the
structure to its before damaged condition would equal or exceed 50 percent of the market value of
the structure before the damage occurred" (44 CFR§ 59.1).
Substantial Improvement. Any reconstruction, rehabilitation, addition, or other improvement of a
structure, the cost of which equals or exceeds 50 percent of the market value of the structure before
the "start of construction" of the improvement. This term includes structures that have incurred
"substantial damage," regardless of the actual repair work performed. The term does not, however,
include either:
(1) Any project for improvement of a structure to correct existing violations of state or local
health, sanitary, or safety code specifications which have been identified by the local code
enforcement official and which are the minimum necessary to assure safe living conditions or
(2) Any alteration of a"historic structure," provided that the alteration will not preclude the
structure's continued designation as a"historic structure" (44 CFR§ 59.1).
Variance. "Grant of relief by a community from the terms of a flood plain management regulation"
(44 CFR§ 59.1).
Wave reflection. Return or redirection of a wave striking an object.
Wave runup. "Rush of wave water running up a slope or structure" (ASCE 24-14). Wave runup occurs as
waves break and run up beaches, sloping surfaces, and vertical surfaces.
NFIP TECHNICAL BULLETIN 0 JULY 2019 23
6 Supplemental Information
6.1 How to Obtain Technical Bulletins
Download Technical Bulletins at no charge from the FEMA website at https://www.fema.gov/
nfip-technical-bulletins.
Order Technical Bulletins at no charge from the FEMA Publications Warehouse by:
• Calling 1-800-480-2520, Monday through Friday between 8 a.m. and 5 p.m. Eastern
• Faxing a request to 1-719-948-9724
• Sending an email to FEMApubs@gpo.gov
6.2 How to Submit Comments on the Technical Bulletins
FEMA welcomes your comments and recommendations on the Technical Bulletins and may include,
for example:
• Requests for clarifications of the guidance in the Technical Bulletins
• Requests for additional guidance
• Recommendations for new Technical Bulletins
Send your comments to:
DHS/FEMA
ATTN: Federal Insurance and Mitigation Administration,
Risk Management Directorate—Building Science Branch
400 C Street, S.W., Sixth Floor
Washington, DC 20472-3020
6.3 How to Get More Information
For questions on any of the Technical Bulletins, email the Building Science Helpline at FEMA-
buildingsciencehelp@fema.dhs.gov or call 1-866-927-2104.
For additional guidance on NFIP regulatory requirements, contact your NFIP State Coordinating Agency
(www.floods.org) or the FEMA Regional office in your Region (see Section 6.4).
6.4 FEMA Regional Offices
The locations of FEMA Headquarters and the 10 FEMA Regional Offices are shown in Figure 3, and
addresses and telephone numbers are listed in Table 3. Staff members of the FEMA Regional Offices for
your area can provide you with more information about the NFIP and Technical Bulletins.
24 NFIP TECHNICAL BULLETIN 0 JULY 2019
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'
FEMA/FIMA — 400 C Street, S.W. 202-646-2500
Headquarters Washington, DC 20472-3020 800-621-FEMA(3362)
TTY: 800-462-7585
Region I Connecticut, Maine, 99 High Street 877-336-2734
Massachusetts, New Boston, MA 02110
Hampshire, Rhode Island,
Vermont
Region II New Jersey, New York, Puerto One World Trade Center 212-680-3600
Rico, Virgin Islands 52nd Floor
New York, NY 10007-0101
Region III Washington, D.C., Delaware, 615 Chestnut Street 215-931-5500
Maryland, Pennsylvania, One Independence Mall, 6th Floor
Virginia, West Virginia Philadelphia, PA 19106-4404
Region IV Alabama, Florida, Georgia, 3003 Chamblee Tucker Road 770-220-5200
Kentucky, Mississippi, North Atlanta, GA 30341-41 1 2
Carolina, South Carolina,
Tennessee
Region V Illinois, Indiana, Michigan, 536 South Clark Street, Sixth Floor 312-408-5500
Minnesota, Ohio, Wisconsin Chicago, IL 60605-1521
Region VI Arkansas, Louisiana, New Federal Regional Center 940-898-5399
Mexico, Oklahoma, Texas 800 North Loop 288
Denton, TX 76209-3698
Region VII Iowa, Kansas, Missouri, 9221 Ward Parkway, Suite 300 816-283-7061
Nebraska Kansas City, MO 64114-3372
Region VIII Colorado, Montana, North Denver Federal Center 303-235-4800
Dakota, South Dakota, Utah, Building 710, Box 25267
Wyoming Denver, CO 80255-0267
Region IX Arizona, California, Hawaii, 1111 Broadway, Suite 1200 510-627-7100
Nevada, American Samoa, Oakland, CA 94607-4052 Pacific Area Office:
Commonwealth of the Northern 808-851-7900
Mariana Islands, Federated
States of Micronesia, Guam,
Republic of the Marshall
Islands,
Region X Alaska, Idaho, Oregon, Federal Regional Center 425-487-4600
Washington 130 228th Street, SW
Bothell, WA 98021-8627
Other Federal agencies that provide floodplain management assistance include the U.S. Army Corps of
Engineers and the U.S. Soil Conservation Service. For their nearest locations, see http://www.usace.army.
mil/Locations.aspx and http://www.nres.usda.gov/wps/portal/nres/sitenav/soils/states/.
26 NFIP TECHNICAL BULLETIN 0 JULY 2019
7 Index of Key Words and Subjects
in the Technical Bulletins
The numbers in the index indicate the Technical Bulletin number.
accessory structures, 1, 5, 7 NFIP requirements for construction, 11
basement foundation,with lowest openings at the decks and patios, as possible obstructions in
BFE, 10 Zone V, 5
below-grade parking detached garages, elevation requirement in
garage, considered a basement, 6 Zone V, 5
garage, defined, 6 drainage considerations, 5, 11
in Zone A and Zone V,when allowed, dry floodproofing, 3
requirements for, 6 elevators
best practices for corrosion resistance, 8 attached to or underneath Zone V structures, 5
best practices for crawlspace foundations in the components,location of in relation to the
SFHA, 11 BFE, 4
bracing, see foundation, bracing electrical equipment, location of in relation to
breakaway wall the BFE, 4
failure modes, 9 insurance considerations, 4
in Zone V, made of flood damage-resistant types of, 4
materials, 2, 9 enclosed areas, 1, 2, 4, 5, 9
insurance considerations, 9 fill
NFIP regulatory requirements, 9 areas where prohibited, 5, 10
specifications for NFIP-compliant as obstruction beneath buildings in Zone V, 5
construction, 9 placed to remove land from the SFHA, 10
breaking wave, impact on vertical surface, 9 proper placement of, 10
bulkheads, as possible obstructions in Zone V, 5 float switch, use of in flood areas (for elevator
community permitting,administrative options cab), 4
for, 10 flood forces on buildings, 1, 3, 4, 5, 9, 10, 11
continuous load path, importance of selecting flood insurance considerations, 1, 2, 3, 4, 5, 6, 7,
proper connectors and fasteners, 8 9, 10, 11
corrosion flood damage-resistant
classes of building exposure to, 8 elevator components, use of, 4
causes of, 8 flooring materials, 2
control of, 8 materials, 2, 8, 11
identifying high-risk buildings, 8 materials, classifications, 2
light gauge metal connectors, 8 wall and ceiling materials, 2
planning for, 8 floodproofing
rates of, 8 below-grade parking beneath non-residential
corrosion-resistant materials for metal connectors buildings, design requirements for, 6
and fasteners, 8 certificate, non-residential, 3
crawlspace Emergency Operations Plan, minimum
foundation, 10, 11 acceptable, 3
NFIP TECHNICAL BULLETIN 0 JULY 2019 27
Inspection and Maintenance Plan, 3 openings for foundations in Zone A, 1
recognition of for insurance rating purposes, pre-engineered below-grade crawlspace
3, 6 foundation guidance, 11
foundation pools, see swimming pools
bracing, as possible obstructions in Zone V, 5 preservative-treated wood, chemicals used and
flood risk, summary table, 10 corrosion, 2, 8
in Zone A, 1 professional certification, 5, 10
openings in Zone A, size,how to calculate, I sample form, 10
vents, 1 reasonably safe from flooding
freeboard, recommendations, 3, 10 defined, 10
free of obstruction NFIP regulations concerning, 10
definition of, 5 requirements, additional for below-grade
designing a foundation system in Zone V, 5 crawlspaces, 11
requirements in Zone V, 5 safety factor for foundation openings, 1
functionally dependent use, 7 salt spray from breaking waves, 8
galvanizing, 8 screening in Zone V, made of flood-resistant
garage doors, 1, 5, 7,9 materials, 2
to meet the openings requirement, 1 shear walls, 5
garages slabs-on-grade 5, 10
attached to non-residential structures, 7 spas in Zone V, 5
attached to residential buildings, 1, 7 stem wall foundation, 1, 10
below-grade, 6 substantially impermeable, 3
detached from structures, 7 Substantial Damage, foundation wall openings
grade beams, as possible obstructions in Zone V, 5 requirement, 1
high hazard area, safety and access in, 3, 5 Substantial Improvement, foundation wall
historic buildings, 7 openings requirement, 1
hydrodynamic forces, 1, 3, 4, 5, 6,9, 11 sump pump, requirements, 3,10
hydrostatic forces, 1,3, 4, 6, 10, 11 swimming pools in Zone V, 5
hydrostatic loads, equalized by openings, 1 U.S. Army Corps of Engineers, Flood Proofing
hydrostatic pressure, how to relieve, 1 Regulations (1995), 2
insect screening,for below building enclosures, utilities, access, and ventilation openings, 3, 5, 11
1, 9 variances
insurance coverage for basement flooding, from NFIP requirements, 7
restrictions, 10 issuance in designated floodways, 7
lattice work, for below-building enclosures, 9 wet floodproofing
lattice work in Zone V, made of flood-resistant allowable structures and uses, 7
materials, 2 definition of, 7
lowest floor, definition of, 1, 3 engineering considerations, 7
non-residential floodproofing certificate, how to flood insurance implications, 7
fill out, 3 planning considerations, 7
28 NFIP TECHNICAL BULLETIN 0 JULY 2019
8 References
Section 8.1 lists the references that are cited in this Technical Bulletin. Section 8.2 lists additional
resources related to NFIP requirements.
8.1 References
ASCE/SEI (American Society of Civil Engineers / Structural Engineering Institute). 2014. Flood
Resistant Design and Construction. ASCE/SEI 24-14.Available at https://ascelibrary.org/doi/
book/10.1061/9780784413791.
FEMA (Federal Emergency Management Agency).Various. Flood Insurance Manual.Available at https://
www.fema.gov/flood-insurance-manual.
FEMA.Various. NFIP Technical Bulletins. Current editions available at https://www.fema.gov/
nfip-technical-bulletins.
— Non-Residential Floodproofang—Requirements and Certification for Buildings Located in Special Flood
Hazard Areas. Technical Bulletin 3.
— Wet Floodproofing Requirements for Structures Located in Special Flood Hazard Areas. Technical
Bulletin 7.
FEMA. 2010. Substantial Improvement/Substantial Damage Desk Reference. FEMA P-758.Available at https://
www.fema.gov/media-library/assets/documents/18562.
FEMA. 2018. Answers to Questions About Substantially Improved/Substantially Damaged Buildings. FEMA 213.
Available at https://www.fema.gov/media-library/assets/documents/169099.
ICC (International Code Council). 2018. International Building Code.Available at
https://www.iccsafe.org/.
ICC. 2018. International Existing Building Code.Available at https://www.iccsafe.org/.
ICC. 2018. International Residential Code.Available at https://www.iccsafe.org/.
ICC and FEMA. 2014. Reducing Flood Losses Through the International Codes: Coordinating Building Codes and
Floodplain Management Regulations, 4th Edition.Available at https://www.fema.gov/media-library/
assets/documents/96634.
NFIP TECHNICAL BULLETIN 0 JULY 2019 29
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