Public Comments

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ASFPM’S RECOMMENDED UPDATES TO THE
DRY FLOODPROOFING CERTIFICATE,
WITH SUPPORTING CONTEXT

General
•

Machinery and equipment Installations that are outside of dry floodproofed areas of the
building, must be elevated or within separate “floodwall” type structures (see FEMA P-936 for
component protection). If elevated on platforms or pedestals, then it is important to have the
surveyed elevation of the lowest machine or piece of equipment. Add to Section III a new “D” to
capture lowest elevation of machinery and equipment that is located outside of the dry
floodproofed areas of the building.

•

Purpose of Certification: This sentence “However, to be in compliance with the requirements of
American Society of Civil Engineers (ASCE) 24, Flood Resistant Design and Construction, one foot
is subtracted from the dry floodproofed elevation.” Should be removed because it is only in the
commentary section of ASCE 24 and is in there based on NFIP’s old rating methodology.

•

Purpose of Certification: This sentence “Therefore, a building must be dry floodproofed to one
foot above the BFE to be considered for floodproofing credit. For B, C, D, or X flood zones, the
building's dry floodproofed design elevation must be at least two feet above the natural HAG to
be considered for floodproofing credit.” should be removed as it is no longer correct due to NFIP
Risk Rating 2.0’s rating methodology.

•

The Certificate needs somewhere for the user to indicate which edition of ASCE 24. Something
being built in 2028 will likely/should be certified to 24-24, but if you have 2018 building it was
likely design and constructed to 24-14.

•

Purpose of Certification: Recommended language changes o

A dry floodproofed building is a building that has been designed and constructed to be
watertight (substantially impermeable to floodwaters) below the BFE and with structural
components having the capability of resisting hydrostatic and hydrodynamic loads and
effects of buoyancy. Before a dry floodproofed building is designed, numerous planning
considerations, including flood warning time, uses of the building, mode of entry to and
exit from the building and the site in general, floodwater velocities, flood depths, debris
impact potential, flood frequency, evaluation of passive and active flood barriers for
opening protection, and any other State and local requirements must be addressed to
ensure that dry floodproofing will be a viable floodplain management measure.

o The minimum NFIP requirement is to dry floodproof a building to the BFE. However, to

be in compliance with the requirements of American Society of Civil Engineers (ASCE) 24,
Flood Resistant Design and Construction, one foot is subtracted from the dry
floodproofed elevation. Therefore, a building must be dry floodproofed to one foot above
the BFE to be considered for floodproofing credit. For B, C, D, or X flood zones, the
building's dry floodproofed design elevation must be at least two feet above the natural
HAG to be considered for floodproofing credit. NOTE: Per the latest release of ASCE 24,

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ASCE 24-24, the Flood Hazard Area is expanded to the 500-year floodplain for Flood
Design Classes 2, 3, and 4 structures, flood loads for use in design are now calculated in
accordance with ASCE 7-22, Supplement 2, and Design Flood Elevation (DFE)
requirements are based on the Flood Design Class of the building.

Section I
•

Specify what units the velocity should be given in (ft/s, m/s, etc.)

•

Adding the following questions:
o Does the FIRM have a defined Floodway?
o Is the property located adjacent to the Floodway?
o With regards to the Alluvial Fans question: Are stormwater pumps used in this area?

Section II
•

Remove the following sentence from the first bullet “For insurance rating purposes in all zones
except for B, C, D, or X, the building's dry floodproofed design elevation must be at least one foot
above the BFE to be considered for floodproofing credit. For B, C, D, or X Zones, the building's dry
floodproofed design elevation must be at least two feet above the natural HAG to be considered
for floodproofing credit. If the building is not dry floodproofed to the above-mentioned
standards, then the building will be ineligible for floodproofing credit.”
o This should be removed as it is no longer correct due to NFIP Risk Rating 2.0’s rating
methodology. Consider replacing with “The certificate along with the documentation
found in the instruction section can potentially qualify you for a dry floodproofing
credit.”

•

Remove the following sentence from the second bullet: “Flood damage resistant materials are
used for all areas where seepage is intended to collect inside the dry floodproofed areas up to at
least 4 inches above the floor.”
o Denver has a more restrictive seepage rate requirement where the seepage is any dry
floodproofed area would never reach this 4inch depth and so does not require flood
damage resistant materials up to at least the 4 inches. 4 inches should not be a
certification requirement if communities have more restrictive requirements as this
could become very costly to a project.

•

Recommended language changes:
o Briefly list measures incorporated into the design to meet the performance criteria for
dry floodproofing and attach calculations showing the structure is designed with
structural components that have the capability of resisting hydrostatic and
hydrodynamic loads and the effects of buoyancy and will be watertight and substantially
impermeable to the passage of water. Note measures for walls, slabs, and flood barriers.
For flood barriers (including flood glazing), list product name, manufacturer name,
compliance in certification to performance testing to ANSI/FM 2510 standards (as
required by ASCE 24-24), and if it is a passive or active flood protection measure.

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o

Non-Residential Dry Floodproofed Design Certification: I certify the structure, based
upon development and/or review of the design and specifications for construction, has
been designed in accordance with the accepted standards of practice (ASCE 24-05, ASCE
24-14, ASCE 24-24 or their equivalent) and the following provisions.
▪

The structure, together with attendant utilities and sanitary facilities will be
watertight to the dry floodproofed design elevation indicated above, will be
substantially impermeable to the passage of water, and shall perform in
accordance with the 44 Code of Federal Regulations (44 CFR 60.3(c)(3)).

▪

All structural components are capable of resisting hydrostatic and hydrodynamic
flood forces, including the effects of buoyancy, and anticipated debris impact
forces up to the dry floodproofed design elevation. Flood damage-resistant
materials are used for all areas where seepage is intended to collect inside the
dry floodproofed areas up to at least 4 inches above the floor.

▪

Any flood barriers (including flood glazing) are complying in certification to
performance testing to ANSI/FM 2510 standards (as required by ASCE 24-24).

Section III
•

Remove the following sentence from the note “For insurance rating purposes in all zones except
for B, C, D, or X, the building's dry floodproofed design elevation must be at least one foot above
the BFE to be considered for floodproofing credit. For B, C, D, or X Zones, the building's dry
floodproofed design elevation must be at least two feet above the natural HAG to be considered
for floodproofing credit. If the building is not dry floodproofed to the above-mentioned
standards, then the building will be ineligible for floodproofing credit.”
o This should be removed as it is no longer correct due to NFIP Risk Rating 2.0’s rating
methodology. Consider replacing with “The certificate along with the documentation
found in the instruction section can potentially qualify you for a dry floodproofing
credit.”

•

Recommended language changes:
o (Note: For insurance rating purposes in all eligible zones inside the SFHA, the building's
dry floodproofed design elevation must be at least one foot above the BFE to be
considered for floodproofing credit. For B, C, D, or X Zones, the building's dry
floodproofed design elevation must be at least two feet above the natural HAG. If the
building is not dry floodproofed to the above-mentioned standards, then the building will
not be considered for floodproofing credit. See the Instructions section for information
on documentation that must accompany this certificate if being submitted for flood
insurance rating purposes. Per the latest release of ASCE 24, ASCE 24-24, the Flood
Hazard Area is expanded to the 500-year floodplain for Flood Design Classes 2, 3, and 4
structures, flood loads for use in design are now calculated in accordance with ASCE 722, Supplement 2, and Design Flood Elevation (DFE) requirements are based on the Flood
Design Class of the building.)

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Section IV
•

Remove the bullet regarding seepage rate requirements. See above comments from Denver

•

Recommended language changes:
o I certify the structure, based upon development and/or review of the design,
specifications, as-built drawings for construction and physical inspection, has been
designed and constructed in accordance with the accepted standards of practice (ASCE
24-05, ASCE 24-14, ASCE 24-24 or their equivalent) and any alterations also meet those
standards and the following provisions. Non-controllable factors that could affect the
building’s floodproofed design performance do not apply.
^ Reasoning for this above are that there are non-controllable factors that are out of the
signer’s control such as the deployment of active flood barriers.
▪

The structure, together with attendant utilities and sanitary facilities is
watertight to the dry floodproofed design elevation indicated above, is
substantially impermeable to the passage of water, and shall perform in
accordance with the 44 Code of Federal Regulations (44 CFR 60.3(c)(3)).

▪

All structural components are capable of resisting hydrostatic and hydrodynamic
flood forces, including the effects of buoyancy, and anticipated debris impact
forces up to the dry floodproofed design elevation.

▪

Any flood barriers (including flood glazing) are complying in certification to
performance testing to ANSI/FM 2510 standards (as required by ASCE 24-24).

▪

The floodproofed elevation is in accordance with the design and any
alteration(s) to the design.

▪

Flood damage-resistant materials have been incorporated/used in all areas
where seepage would collect inside the dry floodproofed areas up to at least 4
inches above the floor.

▪

Construction matches the latest approved design drawings.

Required Documentation
•

Comprehensive Flood Emergency Operations Plan (2f): Define conditions, such as Hurricane
Watch.

•

REQUIRED DOCUMENTATION (page 6 of 8). Modify #4 Building Owner statement to require
acknowledgement of the Inspection and Maintenance Plan.

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•

•

Comprehensive Flood Emergency Operations Plan recommended language changes:
o

2a. The personnel, equipment, tools, and supplies needed to deploy all dry floodproofing
system components with sufficient time prior to the onset of flooding or conditions such
as high winds that could interfere with efficient deployment of measures. Identify the
single personnel hours needed to deploy all dry floodproofing components and list
compliance to ASCE 24-24 requirements based on the Flood Design Class of the building.
Identify the flood warning system being utilized (e.g. community warning system or flood
warning system that is specific to the facility) per ASCE 24-24.

o

2g. Instructions for installing or deploying each dry floodproofing measure and the order
of installation if important for effectiveness. For structures with permanent automatic
passive measures the plan should include an audio or visual device to alert the building
owner or designated representative as well as occupants that the measures have been
implemented and additional steps in the operations plan may be triggered.

o

2k. Requirements for installation and full-scale deployment, drills and training program
in the presence of an inspection agency (at least once a year)

o

2m. Documentation of all substantially impermeable walls and any other portion of the
building required to have protected non-flood openings or penetrations shall be
permanently identified with signs or stenciling.

Comprehensive Inspection and Maintenance Plan (3j) recommended language changes:
o

Contact information for the manufacturer and installer of the shields and other
components to determine the availability of replacement gaskets, seals, and other parts
and to ask questions.

Instructions
•

Recommended language changes for SECTION IV – DRY FLOODPROOFED CONSTRUCTION
CERTIFICATION:
o

Section IV is to be completed by a Registered Professional Engineer or Architect licensed
in the state where the building is located to certify the structure, based upon
development and/or review of the design, specifications, as-built drawings for
construction and physical inspection, has been designed and constructed in accordance
with the accepted standards of practice (ASCE 24-05, ASCE 24-14, ASCE 24-24 or their
equivalent) and any alterations also meet those standards and the provisions listed in
Section IV.

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