NFIP
Download
1 / 72

Technical Standards - PowerPoint PPT Presentation


  • 115 Views
  • Updated On :

NFIP. National Flood Insurance Program Administered by FEMA. Technical Standards. TOPICS. Elevation Wet Floodproofing (Dry) Floodproofing of Non-residential Structures . MORE TOPICS . . . . Utilities and Building Systems Manufactured Home Standards. Elevation.

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'Technical Standards' - yule


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
Slide1 l.jpg

NFIP

National Flood Insurance Program Administered by FEMA

Technical Standards


Topics l.jpg
TOPICS

  • Elevation

  • Wet Floodproofing

  • (Dry) Floodproofing of Non-residential Structures


More topics l.jpg
MORE TOPICS . . .

  • Utilities and Building Systems

  • Manufactured Home Standards


Elevation l.jpg
Elevation

  • Requirements in A and V Zones

  • Elevated Foundations

  • FEMA’s Technical Bulletins and Technical References


Elevation requirements for zones ae ah and a1 30 l.jpg
Elevation Requirements for Zones AE, AH, and A1-30

  • All new construction and substantial improvement shall have the Lowest Floor, including basement, elevated to or above the BFE

  • The reference level for the lowest floor is measured at the top of the sub-floor


Elevation requirements for zone ao l.jpg
Elevation Requirements for Zone AO...

All new construction or substantial improvement, shall have the lowest floor, including basement elevated above the highest adjacent grade to a height equal to or exceeding the depth number specified in feet on the FIRM.


Elevation requirements for zone ao7 l.jpg
...Elevation Requirements for Zone AO

If no depth number is specified, then the Lowest Floor must be elevated at least two feet above the highest adjacent grade.


Elevation requirements for zones ve v1 30 l.jpg
Elevation Requirements for Zones VE & V1-30...

  • 1. All new construction and substantial improvement shall be elevated on adequately anchored pilings or columns…


Elevation requirements for zones ve v1 3010 l.jpg
...Elevation Requirements for Zones VE & V1-30...

  • ...and securely anchored to such pilings or columns so that the lowest horizontal portion of the structural members of the lowest floor is elevated to or above the BFE.


Elevation requirements for zones ve v1 3011 l.jpg
...Elevation Requirements for Zones VE & V1-30...

  • 2. All new construction shall have the space below the lowest floor free of obstructions or constructed with breakaway walls…




Elevation requirements for zones ve v1 3014 l.jpg
...Elevation Requirements for Zones VE & V1-30

  • ...Such enclosed space shall not be used for human habitation and will be usable solely for parking of vehicles, building access, or storage.


Elevated foundations l.jpg
ELEVATED FOUNDATIONS

  • Fill

  • Perimeter Wall

  • Pilings



Criteria for elevation on fill l.jpg
Criteria for Elevation on Fill

  • All A Zones, with low-velocity flooding (less than 5 feet per second)

  • Usually limited to three or four feet in height


Standards for elevation on fill l.jpg
Standards for Elevation on Fill...

  • Fill should be placed in maximum 12-inch lifts

  • Fill should be compacted to 95% of the maximum density obtainable with the Standard Proctor Test Method (ASTM Standard D-698)


Standards for elevation on fill19 l.jpg
…Standards for Elevation on Fill

  • Fill slopes should be no steeper than 1.0-foot vertical to 1.5-feet horizontal

  • Fill should extend a minimum of 15 feet beyond all sides of the structure

  • Erosion protection is required


Perimeter wall foundation l.jpg
Perimeter Wall Foundation

Opening

(typical))


Criteria for elevation on perimeter wall foundations l.jpg
Criteria for Elevation on Perimeter Wall Foundations

  • All A Zones, with low-velocity flooding (less than 5 feet per second)

  • Usually limited to three or four feet in height above grade

  • Enclosed areas below the lowest floor must have openings to equalize hydrostatic pressures


Standards for elevation on perimeter wall foundations l.jpg
Standards for Elevation on Perimeter Wall Foundations...

  • Fully enclosed areas below the lowest floor shall be designed to automatically equalize hydrostatic flood forces on exterior walls by allowing for the automatic entry and exit of floodwaters…


Standards for elevation on perimeter wall foundations23 l.jpg
...Standards for Elevation on Perimeter Wall Foundations

  • Designs must be certified by a registered engineer or architect, or meet or exceed the minimum opening criteria mentioned earlier


Minimum standards for foundation openings l.jpg
Minimum Standards for Foundation Openings...

1) A minimum of two openings on different sides of the enclosed area having a total net area of not less than one square inch for every square foot of enclosed area subject to flooding.


Minimum standards for foundation openings25 l.jpg
...Minimum Standards for Foundation Openings

2) The bottom of all openings shall be no higher than one foot above grade.

3) Openings may be equipped with screens, louvers, valves, or other “automatic” coverings



Criteria for pile foundations l.jpg
Criteria for Pile Foundations

  • All A and V Zones, with large depths of flooding and high velocities

  • Particularly well suited for coastal high hazard areas


Key considerations for pile foundations l.jpg
Key Considerations for Pile Foundations

  • Pile embedment method and depth

  • Bracing to resist lateral forces

  • Proper connections (critical in coastal high hazard areas)

    • Foundation to floor beam

    • Floor beam to floor joist

    • Floor joist to wall

    • Wall to roof


Other elevated foundation systems l.jpg
Other Elevated Foundation Systems

  • Shear Walls

  • Posts

  • Piers


Reminder in v zones l.jpg
Reminder in V Zones

Corrosion protection is needed for foundations built with reinforced concrete or steel I-beams.


Fema technical bulletins l.jpg
FEMA Technical Bulletins...

  • “Openings in Foundation Walls”, FIA-TB-1 April 1993

  • “Free of Obstruction Requirements”, FIA-TB-5, April 1993

  • “Corrosion Protection for Metal Connectors in Coastal Areas”, FIA-TB-8, August 1996


Fema technical bulletins32 l.jpg
...FEMA Technical Bulletins

  • “Design and Construction Guidance for Breakaway Walls Below Elevated Coastal Building”, FIA-TB-9, September 1999


Other fema publications l.jpg
Other FEMA Publications

  • “Elevated Residential Structures”, FEMA-54, March 1984

  • “Coastal Construction Manual”, FEMA-55, June 2000

  • “Above the Flood: Elevating Your Floodprone House”, FEMA 347, May 2000


Wet floodproofing l.jpg

WET FLOODPROOFING

NATIONAL FLOOD INSURANCE PROGRAM


Wet floodproofing definition l.jpg
Wet Floodproofing Definition

  • Permanent measures applied to a structure that prevent or provide resistance to damage from flooding by allowing flood waters to enter and exit the structure.

  • Note: Floodproofing techniques are allowed in A Zones only!


When to use wet floodproofing l.jpg
When to Use Wet Floodproofing

  • Enclosed areas below the BFE that are used for parking, building access, or limited storage

  • Attached garages below the BFE


Other possible applications of wet floodproofing l.jpg
Other Possible Applications of Wet Floodproofing...

  • If accompanied by a variance, Wet Floodproofing may also be used for the following…

  • Structures functionally dependent on close proximity to water

  • Historic structures. . .


Other possible applications of wet floodproofing39 l.jpg
...Other Possible Applications of Wet Floodproofing

  • Some accessory and agricultural structures

  • Pre-FIRM structures not substantially improved or damaged


Wet floodproofing and flood resistant materials l.jpg
Wet Floodproofing and Flood Resistant Materials

  • Flood resistant materials must be used for those areas of a structure below the base flood elevation regardless of the expected or historic flood duration.


Fema technical bulletins41 l.jpg
FEMA Technical Bulletins

  • “Wet Floodproofing Requirements”, FIA-TB-7, December 1993

  • “Flood Resistant Materials Requirements”, FIA-TB-2, April 1993


Dry floodproofing l.jpg
(DRY) FLOODPROOFING

  • ONLY NON-RESIDENTIAL STRUCTURES MAY BE FLOODPROOFED IN LIEU OF ELEVATION.

  • Note: Floodproofing is allowed in A Zones only!


Dry floodproofing definition l.jpg
Dry Floodproofing Definition

  • Permanent and temporary measures applied to a structure that prevent damage from flooding by making a building watertight, substantially impermeable to floodwaters.


Dry floodproofing45 l.jpg
“DRY” FLOODPROOFING

  • Planning requirements

  • Design

  • Construction


Planning considerations for dry floodproofing l.jpg

Warning Time

Safety and Access

Flood Velocities

Flood Depths

Planning Considerations For Dry Floodproofing...


Planning considerations for dry floodproofing47 l.jpg

Debris

Flood Frequency

Emergency Operation Plan

Inspection Plan

Maintenance Plan

...Planning Considerations For Dry Floodproofing


Dry floodproofing design requirements l.jpg
“DRY” FLOODPROOFING DESIGN REQUIREMENTS

  • The building must be watertight to at least the BFE.

  • The building’s walls must be “substantially impermeable to the passage of water.”

  • Have structural components capable of resisting hydrostatic and hydrodynamic loads and effects of buoyancy.


More design requirements l.jpg
MORE DESIGN REQUIREMENTS. . .

  • Building utilities and sanitary facilities must be located above the BFE, completely enclosed within the building’s watertight walls, or made watertight and capable of resisting damage during flood conditions.

  • Must be certified by a registered professional engineer or architect.



Fema technical bulletins and references l.jpg
FEMA Technical Bulletins and References

  • “Non-Residential Floodproofing - Requirements and Certification”, FIA-TB-3, April 1993

  • “Below-Grade Parking Requirements”, FIA-TB-6, April 1993

  • “Floodproofing Non-Residential Structures”, FEMA 102, May 1986


Utilities and building systems l.jpg

UTILITIES AND BUILDING SYSTEMS

NATIONAL FLOOD INSURANCE PROGRAM


Utilities and building systems54 l.jpg
Utilities And Building Systems

  • Standards

  • Basic Protection Measures

  • Examples

  • FEMA Technical Bulletins


Utilities and building systems include l.jpg

Heating

Ventilation

Air Conditioning Systems

Fuel Systems

Electrical Systems

Sewage Management Systems

Potable Water Systems

Utilities And Building Systems Include


Standards for utilities and building systems l.jpg
Standards For Utilities And Building Systems

  • All new construction and substantial improvement shall be constructed with electrical, HVAC, plumbing and other service facilities that are designed and/or located so as to prevent water from entering or accumulating within the components during conditions of flooding.


Basic protection methods l.jpg
Basic Protection Methods

  • Elevation

  • Component Protection


Slide58 l.jpg

UTILITY LOCATION SCHEMATIC

AC Unit

Water

Heater

Propane

Gas

Electrical

Box

Well

Head

BFE


Fema technical references l.jpg
FEMA Technical References

  • “Protecting Building Utilities From Flood Damage”, FEMA 348, November 1999

  • “Homeowner’s Guide to Retrofitting”, Chapter 8, FEMA 312, June 1998


Manufactured home standards l.jpg

MANUFACTURED HOME STANDARDS

NATIONAL FLOOD INSURANCE PROGRAM


Manufactured home standards66 l.jpg
Manufactured Home Standards

  • Manufactured Home Requirements

  • Exception for existing parks with no substantial damage

  • Technical Reference


Manufactured home requirements l.jpg
Manufactured Home Requirements...

  • All manufactured homes that are placed or substantially improved within the SFHA shall:

  • 1) be elevated on a permanent foundation such that the lowest floor of the manufactured home is elevated to or above the BFE; and


Manufactured home requirements68 l.jpg
...Manufactured Home Requirements

  • 2) be securely fastened to an adequately anchored foundation system to resist flotation, collapse and lateral movement.


Manufactured home exception l.jpg
Manufactured Home Exception...

  • An exception was made for existing parks with no “substantial damage”:

  • 1) The lowest floor of the manufactured home must be elevated at or above the BFE and anchored to a permanent foundation system; or


Manufactured home exception70 l.jpg
...Manufactured Home Exception

  • 2) the manufactured home chassis must be supported by reinforced piers or other foundation elements of at least equivalent strength that are no less than 36 inches in height above grade.


Fema technical reference l.jpg
FEMA Technical Reference

  • “Manufactured Home Installation in Flood Hazard Areas”, FEMA 85, September 1985

FEMA 85