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Slide 1
Slide 2
Building Codes and Floodplain Management Laura Ghorbi, PE, CFM
RAMPP FEMA Region III National Flood Insurance Program Essentials
and Best Practices
Slide 3
Objectives Familiarize floodplain administrators with building
codes Familiarize building code officials with floodplain
ordinances Identify where building codes and floodplain ordinances
overlap and where the gaps are Discuss the different approaches to
adopting floodplain management provisions Understand where higher
standards may exist and how to coordinate with the building code
2
Slide 4
Meeting NFIP Requirements NFIP participating municipalities
must adopt and enforce floodplain management regulations that meet
the minimum requirements of the NFIP. The regulations must: Be
legally enforceable Applied uniformly throughout the community
Floodplain regulations are usually found in one of, or a
combination of, five types of regulations: stand alone, zoning
ordinances, building codes, subdivision regulations and sanitary
regulations. 3
Slide 5
ALL development in the SFHA requires a permit Definition of
development (as per 44 CFR 59): Any manmade 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 Poquoson, VA (from FEMA Region III) Ensure you have a
process for capturing all floodplain development Permits Required
for Development
Slide 6
Highlights of NFIP Requirements Set forth in 44 CFR Section
60.3 Site reasonably safe from flooding Construct to minimize flood
damage Use flood damage-resistant materials Foundation and
elevation requirements Design to prevent flotation, collapse,
lateral movement during flooding Design or locate equipment to
prevent water entry Substantial Improvement/Substantial Damage
requirements 5
Slide 7
Flood Damage-Resistant Materials 6 Required below the BFE
Withstand prolonged contact with floodwaters FEMA guidance in
Technical Bulletin 2 Image source: FEMA file photo
Slide 8
Foundation Requirements A Zones Slab-on-fill Fully-enclosed
foundation wall (flood openings required) Open foundation on piers,
posts, pilings, or columns 7 Image source: FEMA Quick Reference
Guide: Comparison of Select NFIP & Building Code Requirements V
Zones Open foundation on columns or pilings Designed by a
registered design professional
Slide 9
Elevation Requirements 8 FEMA Region III, Poquoson, VA FEMA
Region III, Tinicum, PA V Zones: bottom of lowest horizontal
structural member to or above BFE A Zones: top of lowest floor to
or above BFE
Slide 10
Presenters Name June 17, 2003 Structures and utilities must be
anchored to resist the effects of flotation, collapse, and lateral
movement 9 Elevate and Anchor Requirement Foundation Lateral
movement Image source: FEMA file photo
Slide 11
Enclosures Below BFE A Zones Limited to parking, building
access, and limited storage At least two openings no more than 1
foot above grade One square inch of opening for each square foot of
enclosed space Engineered openings required certification 10
Compliant openings V Zones Limited to parking, building access, and
limited storage Space must be free of obstruction, or Breakaway
walls, open lattice, or louvers Yardley Borough, PEMA
Slide 12
Dry Floodproofing Requirements Permitted only for
non-residential structures in A Zone floodplains Structure must be
made watertight To or above BFE (or BFE +1 foot for insurance
purposes) Requires certification by a registered design
professional 11 Image: Whole Building Design Guide, National
Institute of Building Sciences
Slide 13
12 Cost to restore or improve the structure equals or exceeds
50% of its market value If damaged, use the pre-damage market value
Must be brought into full compliance Middletown Borough, Dauphin
County, PA (from PEMA)Town of Bloomsburg, Columbia County, PA (from
PEMA) Substantial Improvement/Damage
Slide 14
Non-Building Development 13 Storage of materials Paving and
grading Placement of fill Recreational vehicles and temporary
structures Alteration of watercourse Must have same or greater
capacity Must maintain capacity over time Image source: SC Quick
Guide for Mapping
Slide 15
NFIP Technical Bulletins NFIP requirements are
performance-based 11 Technical Bulletins provide prescriptive
guidance for compliance 14
Slide 16
I-Codes and Floodplain Management Requirements The flood
provisions of the 2012 and 2009 I-Codes meet or exceed National
Flood Insurance Program minimum requirements for buildings and
structures. I-Codes do not meet the minimum NFIP requirements for
other development unless adopting: In their entirety, Appendix G of
the IBC, Chapter 1 (administration), AND No limiting amendments
15
Slide 17
Prescriptive vs. Performance Prescriptive Code via IRC The more
prescriptive the code, the more engineering is behind the
requirements and the less individual design is required Details the
specifications for construction standards Design professional only
required where proposal is outside of the specifications of the
code Performance Code via IBC Leave it to the designer and engineer
to decide how to achieve that performance Need a technical
professional References other prescriptive standards (like ASCE 24)
16
Slide 18
IBC Appendix G - Flood-Resistant Construction Addresses
flood-related administrative requirements The only place in the
I-Code that addresses development other than buildings 17 G101
Administration G102 Applicability G103 Powers and Duties G104
Permits G105 Variances G201 Definitions G301 Subdivisions G401 Site
Improvement G501 Manufactured Homes G601 Recreational Vehicles G701
Tanks G801 Other Building Work G901 Temp Structures & Temp
Storage G1001 Utility & Miscellaneous Group U
Slide 19
American Society of Civil Engineers (ASCE) Publications ASCE 7,
Minimum Design Loads for Buildings and Other Structures Cited by
IBC Flood loads include: Hydrostatic loads Hydrodynamic loads Wave
loads Impact loads (from debris and ice) ASCE 24, Flood Resistant
Design and Construction Cited by IBC and IRC Specific limitations,
minimum requirements, and performance standards for the design and
construction of buildings and structures in flood hazard areas
18
Slide 20
Administrative Provisions How are administrative provisions of
the codes handled? Many States modify or rewrite Some States allow
communities to write their own Some States use a single chapter for
all codes Duties and powers of the building official Granting
modifications Content of construction documents and plans
Inspections 19
Slide 21
Inspections The Floodplain Administrator and the Building Code
Official are both responsible for ensuring compliance and
confirming as-built conditions I-Codes call for at least: Lowest
floor or footer inspection to be conducted to allow for correction
of possible violation prior to further vertical construction Survey
before final inspection Final as-built inspection 20
Slide 22
Any exemptions within I-Codes or State amendments are
superseded by the NFIP minimum requirement to regulate all
development in the SFHA. 21
Slide 23
BFE vs. DFE Base Flood Elevation (BFE) and Design Flood
Elevation (DFE) DFE is always BFE or higher In most communities,
DFE = BFE DFE is greater than BFE if a community regulates beyond
the SFHA on the effective FIRM DFE is NOT BFE + freeboard Freeboard
is typically included as an additional height above the BFE or DFE
in lowest floor elevation requirements 22
Slide 24
Coastal A Zone 23 Image source: FEMA P-55 Delineated using
LiMWA Flood hazards can be much greater than in riverine Zone A:
Waves 1.5 to 3 feet high are capable of causing structural damage
and erosion Older FIRMs may fail to reflect changing site
conditions as a result of long-term erosion Higher Standard: IBC
places Zone V requirements in the Coastal A Zone where delineated
Higher Standard: IRC requires 1 foot of freeboard in the Coastal A
Zone where delineated
Slide 25
Critical Facilities Higher elevation requirements for critical
and essential facilities, depending on occupancy and purpose of
building 24 Image source: FEMA file photo Image source: stock
photo
Slide 26
Local Officials Need to Know What edition of the code was
adopted and who is the agency? How is the code adopted? (at the
State level, etc.) Are there amendments or modifications? The
regulations in the building codes and local floodplain management
ordinance to meet or exceed the requirements of the NFIP How to
enforce all floodplain management requirements across all codes and
ordinances 25
Slide 27
State Building Code Adoption Include agency references Must
know how it works in each state most important to know who to talk
to and understand how it is adopted 26 Washington, D.C. Department
of Consumer and Regulatory Affairs N/A Delaware No state-wide codes
Adopted at a local or county level Maryland Department of Housing
and Community Development State-wide code Municipalities can adopt
higher standards Pennsylvania Department of Labor and Industry
State-wide code Municipalities can adopt higher standards Virginia
Department of Housing and Community Development State-wide code
Municipalities can adopt higher floodplain standards West Virginia
Fire Commission, Office of State Fire Marshall State-wide code
Municipalities can adopt higher standards
Slide 28
Adoption and Enforcement of the NFIP Minimum Requirements Three
main approaches to adoption and enforcement Stand-alone ordinances
Companion or Wrap-around ordinances I-Codes: in their entirety,
with Appendix G of the IBC, Chapter 1, AND no limiting amendments
27
Slide 29
Stand Alone Ordinances Might be easier to administer and
enforce One ordinance contains all NFIP requirements for
development standards Developers and officials can easily see the
requirements in one place Ensure that all offices/agencies are
aware of floodplain standards when inconsistent May not be
coordinated with other regulations or codes regulations could be in
conflict 28
Slide 30
Companion/Wrap-around Ordinance Use the building code for
design and construction of buildings and structures Use a companion
ordinance for administrative provisions: Adoption of effective maps
(and map revisions) Floodway encroachment analyses SI/SD
determinations Variances/modifications Use a companion ordinance
for development activities that are not regulated by the building
code 29
Slide 31
I-Codes Only Must have both IBC and IRC, with flood provisions
intact Must capture existing buildings Must retain administrative
provisions (flood) Must capture buildings exempt from the code Must
adopt Appendix G (administrative and development other than
buildings) Must understand where each NFIP requirement is met
Amendments must not weaken the code 30
Slide 32
Resolving Conflicts in Regulations If the community has both
floodplain management ordinances and the I-Codes in effect: The
more restrictive prevails Understand which office is responsible
for each requirement Go through coordination process to identify
differences and gaps Decide how best to resolve those differences
and eliminate the gaps (change code, change ordinance, rely on
case-by-case application of more restrictive prevails) 31
Slide 33
32 Flood Resistant Buildings and Development NFIP Regulations
(44 CFR Parts 59 & 60 ) ASCE 7 ASCE 24 Building Code Local
Floodplain Management Regulations* or IBC Appendix G* Local
Floodplain Management Regulations* or IBC Appendix G*
Slide 34
Coordinating the I-Codes and NFIP 33 Worksheets to help ensure
communities meet all NFIP requirements Helps to identify what to
capture in a companion ordinance Crosswalks of I-Codes to NFIP
regulations Sample plan review and inspection checklists Currently
being updated 4 th Edition coming in Summer 2014
Slide 35
The NFIP minimums regulate all development in the SFHA
Remember, nearly all of the NFIP minimum requirements for buildings
and structures are ALREADY found in the building code But, other
forms of development may not be captured in the building code (for
instance, placement of fill) Higher standards likely exist in local
floodplain management ordinances Building Code Officials and
Floodplain Administrators must work together on administration and
enforcement Uncoordinated enforcement results in non-compliance,
higher insurance premiums, and increased risk to life and property.
34 Coordination Matters
Slide 36
Resources and Assistance FEMA Building Science Homepage:
http://www.fema.gov/building- sciencehttp://www.fema.gov/building-
science Click on Building Code Resources Flood Resistant Provisions
of the 2012 and 2009 I-Codes Highlights of ASCE 24-05, Flood
Resistant Design and Construction Provisions of the I-Codes and
ASCE 24 Compared to the NFIP I-Codes vs. NFIP checklists Building
Science Helpline: 1(866) 927-2104 or FEMA-
[email protected][email protected] For further questions on the NFIP,
contact your State Floodplain Manager 35