Understanding Active and Passive Floodproofing Options for Non- Residential Buildings in a Special Flood Hazard Area Course Number: SV003 Learning Units:

Understanding Active and Passive Floodproofing Options for Non-

Residential Buildings in a Special Flood Hazard Area

Course Number: SV003Learning Units: 1Credit Designation: HSW

Provider: Smart Vent Products, IncProvider number: T058

Learning Objectives• Identify the applicable ICC building codes and FEMA regulations pertaining

to non-residential floodproofing options.

• Understand the design benefits for each dry floodproofing and wet floodproofing option.

• Identify design issues and occupants risks associated with active flood proofing techniques and the liability associated with those risks.

• Analyze the difference between Active and Passive floodproofing techniques and how they affect the buildings sustainability.

Course Outline• Section 1 General Overview

• Effects of hydrostatic pressure• NFIP (FEMA) Regulations, ICC building codes, ASCE standards • Define dry and wet floodproofing techniques• Active and passive methods

• Section 2 Dry Floodproofing• Planning considerations & engineering requirements• Active vs Passive methods• FEMA floodproofing certificate• Designer Liability

• Section 3 Wet Floodproofing• Options• Engineered vs non-engineered• ICC-ES Evaluated Products• Project Studies

Section 1• Section 1

• Effects of hydrostatic pressure• NFIP (FEMA) Regulations, ICC building codes, ASCE standards • Define dry and wet floodproofing techniques• Active and passive methods

Hydrostatic Pressure

The Effects of Hydrostatic Force

A B

C D

Floodproofing Options: A Zones

Dry Flood Proofing Wet Flood Proofing

Dry Floodproofing (Resist)• Making a building watertight,

impermeable to flood waters• NFIP allows in non-residential buildings

only• For new construction or substantial

improvements to existing buildings• Acceptable in A, AE, A1-A30, AO, & AH

Zones• Design must be certified (Liability)

Wet Floodproofing (Relieve) • Flood Vents equalize the

hydrostatic pressure• NFIP allows in both residential

and non-residential structures• For new construction or

substantial improvements to existing buildings

• Acceptable in A, AE, A1-A30, AO, & AH Zones

• ICC-ES Certified Options

Additional Floodplain Construction References

2009 IBC ASCE 24-05

Design Plans

Which To Design With?

• Dry Vs Wet• Design differences and costs• Active vs Passive approaches

Section 2

• Dry Floodproofing • Design requirements & materials• Active & passive flood barriers• Flood proofing certificate & liability

Dry Floodproofing

• Planning: Is it possible? – Considerations

• Warning time, Safety & Access• Flood Velocities, Depths, and Debris• Frequency• Emergency Plan• Inspection & Maintenance Plan• Cost• Liability

Warning Time, Safety & Access

• Time is critical• Active flood proofing

measures• Human Stability• Dry Flood Proofing is

not appropriate in a flash flood area.

Flood Velocities, Depths & Debris

• Cost Prohibitive When– Flood Velocities are over 5 feet per second – Base Flood depths in excess of 3 feet

• Impact forces from debris– Calculation assumes 1 second duration of impact– Object estimated at 1,000 pounds

Flood Frequency

• How often• Wear & Tear• Risks of

implementing a emergency plan over and over

• If frequency is not a factor, time to design

Emergency Operation Plan

• Establish the chain of command & responsibilities

• Procedure for notifying necessary parties

• A list of specific duties & location of all dry floodproofing materials

• Evacuation plan- with and without duties

• Annual training drills with community officials

Inspection & Maintenance Plan

• Mechanical equipment, sump pumps & generators

• Inspect & test all flood shields (check gaskets)

• Inspect foundation walls for cracks

• Levees & berms

Dry Floodproofing Certificate

Property Address Section I: FIRM infoSection II: Flood proofing design infoSection III: Certification

Property Address

Section I & II

Section III

Floodplain Impact Consideration

• Increased flood depths, velocities, & flows• Growing the floodplain• ASFPM: No Adverse Impact

– The action of one property owner or community does not adversely affect another

Section 3

• Wet Floodproofing (Passive Solution) • Engineered vs Non-engineered• ICC-ES Evaluated Products• Proper Placement

Three Options

1. ICC-ES Certified Engineered Openings

2. Unique project specific Engineered Openings

3. Non-engineered Openings

Both FEMA and the ICC reference ASCE 24.

ASCE requires that flood openings allow for a 3” sphere to pass through to permit for debris.

3. Non-engineered Openings

• Provide 1 sq in of net open area for every 1sq ft of enclosed area

• An 8”x16” hole with air vent device inserted does NOT provide 128 sq in!

• Account for obstructions to flow• If I-Codes apply, 3” min dimension• Liability: Design Professional, Surveyor,

Construction Official

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• Standard foundation air ventilation devices that can be closed manually, unless they are disabled in the open position

Unacceptable Measures: Page 19 TB-1

Unacceptable Measures: Page 19 TB-1

• Standard foundation air ventilation devices that are designed to open and close based on temperature

Unacceptable Measures: Page 19 TB-1

• Windows below the BFE• Garage Doors without openings installed in them• Standard exterior doors without openings installed in them

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Debris is a Fact of Flood

3” Clarification

2. Unique Engineered Openings

• Designed for a specific project• Certified based on computations (TB1 and

ASCE 24) • I-Codes & ASCE 24: 3” min dimension • Not for mass distributed products• Design must be accompanied by the

original certification • Liability: Licensed Design Professional

Unique Engineered Opening Certificate

• Statement certifying the openings will automatically equalize hydrostatic flood loads

• Range of flood characteristics used • Installation requirements• Property address (must be licensed in that state)• Licensed design professionals name, title,

address, type of license, license number, state in which the license was issued

1. ICC-ES Engineered Openings

• Designed, Tested, & Certified for performance

• Designed and certified based on computations (TB1 and ASCE 24)

• ICC-ES Certifed: AC-364 (AFFV)• I-Codes & ASCE 24: 3” min dimension

ICC-ES Report

Liability For Performance

• Rests on the manufacturer’s shoulders• Each vent is tested• Regular QA inspections

Placement Requirements

Placement Requirements

FEMA Photo

40

Placement Requirements

Sloping Sites: Walk Out Basements

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Dry vs Wet

• William L. Coulbourne, P.E. Floodproofing Report• Dry vs Wet Floodproofing Technologies• Two dry scenarios• Two wet scenarios• 5,000 sq. ft. spaces 4 foot BFE with 1 foot

freeboard

Dry Scenario 1D

• 5,000 sq. ft. full height enclosed space

Dry Scenario 2D

• 5,000 sq. ft. crawlspace

Wet Scenario 1W

• 5,000 sq. ft. full height enclosed space– (13) ICC-ES certified flood vents

Wet Scenario 2W

• 5,000 sq. ft. crawlspace– (13) ICC-ES certified flood vents

Cost Analysis

Summary: Considerations

• Local floodplain ordinances• Health, Safety & Welfare of the Occupants• Active vs Passive techniques• Costs• Liability

Questions