understanding active and passive floodproofing options for non- residential buildings in a special...
TRANSCRIPT
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
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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