Understanding Foundation Flood Vents Non-Engineered vs. Engineered Openings. Amazed 10/5/2015. Notable Natural Disasters in Texas

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1 Understanding Foundation Flood Vents Non-Engineered vs. Engineered Openings Flood Venting 101 Provider: Smart Vent Products, Inc Provider number: T058 1 HSW Credit Amazed Notable Natural Disasters in Texas 1900 Galveston Hurricane Claimed Approx. 8,000+ Lives Deadliest Natural Disaster EVER in the U.S. Third Costliest Hurricane in U.S. History Storm Surge of over 15 feet OVER 3,600 homes were totally destroyed Tropical Storm Allison June of 2001 Lasted for over 2 weeks Over 40 inches of rain 70,000 + Flooded & 2,744 Total Destroyed Worst Flooding was Inland in Houston! 1

2 Who We Are Certified Floodplain Managers Eng. staff works with Underwriters, FEMA and ICC Certified CEU trainer AIA, Code Officials, Surveyors, Insurance Agents 14+ years and 500,000+ vents 25 floods Flood Risk Evaluator Bill Laughlin, CFM Learning Objectives Define the different types of enclosures and what makes them compliant. Understand hydrostatic pressure. Identify FEMA/NFIP Regulations & Building Codes pertaining to Flood Venting. Distinguish the difference between non-engineered and engineered flood vents. Changing Landscape 2012 Biggert - Waters Reform 2014 Grimm Waters (HFIAA) Actuarial Rates Phased in Non-Primary Residences Severe Repetitive Loss Business Properties 18-25% $25 Surcharge Primary $250 Non-Primary 2

3 NFIP Policies In-Force Course Outline Section 1 General Overview Effects of hydrostatic pressure NFIP (FEMA) Regulations, ICC building codes, ASCE standards Wet floodproofing techniques Flood Venting 101 Engineered vs Non-engineered ICC-ES Evaluated Products Proper Placement Elevation Certificates Section 3 Case Studies Extreme Makeover Sea Isle City Ocean City Section 1 Section 1 Basic terms Types of enclosures Effects of hydrostatic pressure NFIP (FEMA) Regulations, ICC building codes, ASCE standards 3

4 NFIP (FEMA) Managed by FEMA Objective is to protect structures built in floodplains Communities must have floodplain ordinances Rewarded with Federally backed flood insurance High Risk = High Premium Basic Terms BFE (Base Flood Elevation) the calculated level flood waters will rise during a base flood. AE & A1-30 Zones: Have established BFE s. Low impact from waves. VE & V1-30 Zones: Have established BFE s. Impact from storm induced waves. Both zones subject to experiencing a 1% annual chance flood event. Raised Wood Floor Design & Construction Options 4

5 Rise Above the Flood There is a 26% chance of experiencing a flood during the lifetime of a 30-year mortgage Source: Federal Emergency Management Agency (FEMA) Raised Floors Can $ave Savings can be realized over the lifetime of a structure by building on a raised foundation. These savings are usually considerable when compared with the one-time increase in construction costs for an elevated foundation. Source: Federal Emergency Management Agency (FEMA) Elevated Residential Structures, truckloads $36,000 5

6 No Adverse Impact 6

7 How Durable is Raised Wood Foundation? Thomas Jefferson s Monticello Foundation Wall Types CMU Chain Wall/Stemwall CMU Piers Drilled Sonotube Piers Poured Concrete Stemwall Treated Wood Kneewall/Stemwall What is an enclosure? Flood Insurance Manual Enclosure. That portion of an elevated building below the lowest elevated floor that is either partially or fully shut in by rigid walls. 7

8 Crawlspaces Full Height Enclosures Flood Insurance Premium Discounts 8

9 Full Height Enclosures (MFH) FEMA Photo Full Height Enclosures (townhouses) Attached Garages BFE BFE 9

10 Detached Accessory Regulated as enclosures Enclosures in V-Zones Floodplain Design, Construction, and Flood Insurance Solutions What makes an enclosure compliant? For floodplain management and construction: NFIP regulations 60.3 Not a basement Unfinished/flood-resistant materials Utilities need to be elevated and protected A zones: Sufficient & adequate openings V zones: Breakaway walls & adequate openings per ASCE

11 31 Not a Basement A floor that is below ground level (grade) on all sides is considered a basement. Limited use Parking of vehicles Storage ( low value storage) Building access (foyers, stairs) 11

12 Hydrostatic Pressure The Effects of Hydrostatic Force A B C D Solid Concrete 12

13 Flood Vents: Passive Relief Flood Vents equalize the hydrostatic pressure NFIP requires in residential structures For new construction or substantial improvements to existing buildings Acceptable in A, AE, A1-A30, AO, & AH Zones ICC-ES Certified Options All The Intimate Details Additional Codes & Standards Referenced by Floodplain Managers, Architects, Engineers 13

14 Section 2 Flood Venting 101 Engineered vs Non-engineered ICC-ES Evaluated Products Proper Placement Elevation Certificates Flood Openings Required in enclosures below the BFE Passive flood relief Equalize hydrostatic loads on enclosure walls Must allow the automatic entry and exit of floodwaters (bi-directional relief) Engineered & Non-engineered Options Objective of a Flood Opening 14

15 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 Non-engineered Openings Provide 1 sq in of 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 Liability: Design Professional, Surveyor, Construction Official 44 Non-Engineered Flood Vent Concrete Air Vent 15

16 Doing the Math This 15.5 x 7.5 air vent does NOT provide sq.in Account for obstructions to flow Back View Measure net open area Unacceptable Measures: Page 19 TB-1 Standard foundation air ventilation devices that can be closed manually, unless they are disabled in the open position 16

17 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 Debris is a Fact of Flood The Road to AC

18 Guidance to consider debris ASCE 24-05: Flood Resistant Design and Construction 3 Interpretation ICC-ES Engineered Opening Requirement 2. Unique Engineered Openings Designed for a specific project Certified based on computations (TB1 and ASCE 24) Not for mass distributed products Design must be accompanied by the original certification Liability: Licensed Design Professional 18

19 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 Don t Believe Everything On The Internet NEW ASCE Standards Further Clarify ICC-ES tested and certified engineered openings of the same size (16x8) provide the same coverage the pictured vents is claiming on their cert. Big difference is ICC-ES certified flood openings are unobstructed during design flood yielding a greater coefficient of discharge. 19

20 Air Vent Summary Air Vent Devices will always be classified as Non-Engineered Openings because they are required by the International Code Council s IRC R408.2 & IBC to be covered for the width and height of the opening with a rodent screen. This covering and other louvers, blades, grills and faceplates put air vents into a partially obstructed category which carries a coefficient of discharge of.20. Using.20 in the calculations yields A=.83 sq.in for every 1 sq.ft of area which is rounded to 1 sq.in of net open area for every 1 sq.ft of enclosed space. Classified as Non-engineered openings by FEMA, ICC, & ASCE 24. Engineered Flood Vent vs. Non-engineered Opening Ex. of an engineered flood vent: has 200 sq. feet of rated flood protection. Most commonly used non-engineered opening: has 32 sq. inches net open area Chicken Gravy 20

21 Engineered vs Non-Engineered 1. ICC-ES Engineered Openings Designed, Tested, & Certified for performance Designed and certified based on computations (TB1 and ASCE 24) ICC-ES Certified: AC-364 (MOFV) I-Codes & ASCE 24: 3 min dimension Engineered Openings A True Engineered Opening mechanically operates, automatically activated to reveal an un-obstructed opening during design flood with a minimum unobstructed opening of 3. Because a rodent screen is required by ICC code for any under floor opening it requires a Engineered Opening to go from a obstructed opening to a unobstructed opening when activated. Flood Door Closed, Obstructing the opening Flood Door Activated, Reveals a Un-obstructed Opening. 21

22 Acceptance Criteria Doing the Math Page 10 ASCE Page 27 TB-1 Engineered Openings: Passive Relief Pictured: ICC-ES Certified Flood Opening after Hurricane Ida (2009) 22

23 Performance Testing ICC-ES Report Liability For Performance Rests on the manufacturer s shoulders Certified to meet the codes Regular QA inspections 23

24 24

25 Placement Requirements Placement Requirements FEMA Photo 25

26 Placement Requirements 76 Sloping Sites: Walk Out Enclosures 77 Elevation Certificates FEMA Elevation Certificate Last check point before CO is granted Surveyor Completes Sections A8 & A9 Flood Vent Info Know your diagrams: 6,7,8,9 EC s Required for Actuarial Rating 26

27 Elevated Building Diagrams Elevation Certificate X X ICC-ES Evaluation Report Attached 16 x8 Smart Vent models: & Certified to cover 200 sq.ft each 27

28 Section 3 Case Studies Extreme Makeover Sea Isle City Ocean City 82 Case study Usea family home Case study Usea family home continued 28

29 Case study Usea family home continued Case study Usea family home continued Case study Usea family home continued 29

30 Case study Usea family home continued Case study Usea family home continued Case study Usea family home continued 30

31 Sea Isle City takes residents to court over noncompliance with FEMA flood standards Neil Byrne, Code Official One of the biggest obstacles Sea Isle City had to overcome while trying to get into the NFIP s CRS program was the mitigation of existing FEMA violations. The majority of these violations had to do with the improper or insufficient flood venting of existing structures. Retro-Fit Into Compliance Over 200 homes retrofitted with proper flood vents in order to meet code Participating in the CRS program benefits the whole community Collectively $800,000 (20% Savings Class 6) 31

32 Crawlspace: short 743 sq.in/ft in flood venting protection Garage: short 355 sq.in/ft in flood venting protection 32

33 Cutting Out The Wrong Product For the Job. 33

34 Removed a total of 5 Gable Vents. Three in the Crawlspace and two in the Garage. After removing the gable vents we discovered they were clogged with debris on the inside. Not noticeable on the outside due to the louvers. 34

35 Louvers, Grills, & Screens impede the flow of flood water into and out of a enclosed space. They also act as nets catching debris and causing the opening to clog. The result. A collapsed foundation due to a build up of hydrostatic pressure Installing The Right Product For The Job 35

36 Retrofitted Three (16 x16 ) Dual Function Flood Vents Into the Crawlspace. Two (16 x16 ) Insulated Flood Vents Into the Garage. Each vent is ICC-ES Certified to cover 400 sq.ft of enclosed area. 36

37 1200 sq.ft of protection With the proper flood vents installed the Elevation Certificate will be changed to reflect the correct flood venting protection for the crawlspace and garage. On average a retrofit like this example with save a home owner 83% on their flood insurance premium and give them piece of mind that there home is properly protected 800 sq.ft of protection Where do I find Foundation Flood Vent Codes? FEMA 44 CFR 60.3(c)(5) FEMA Technical Bulletin TB 1-08 ICC IRC ICC IBC ASCE Summary: Flood Vent Code Minimum of two openings on different walls Bottom of opening no more than one foot above adjacent grade Consider Debris Must automatically allow water in and out, without human intervention. 37

38 Questions Two Series of Vents Dual Function Ideal for Crawlspaces Provides Flood Protection & Natural Air Ventilation Louvers automatically open & close. Fully open at 75 degrees and full closed at 35 degrees Insulated Ideal for areas not requiring air ventilation Seals out cool or warm air with a solid door and weather stripping The 2 Styrofoam core inside of the vent door has an 8.3R value The Dual Function Smart Vent (Crawlspaces) x 8 RO: 16 ¼ x 8 ¼ (one CMU) 200 sq.ft of flood protection 51 sq.in of air ventilation Easy to retrofit into an existing foundation 16 x 16 (aka Stackers) RO: 16 ¼ x 16 ⅜ (two CMU) 400 sq.ft of flood protection 102 sq.in of air ventilation Twice as efficient as a single unit Used when adequate wall space is unavailable 32 x 16 RO: 33 x 16 ⅜ (four CMU) 800 sq.ft of flood protection 204 sq.in of air ventilation Consists of two s installed side x side Excellent for commercial applications and other areas with large square footage 38

39 Powder Coat Paint Options: Black, Grey, Wheat, White Give your projects a aesthetic finish look with these available stock paint options. 316 Marine Grade Stainless Steel is still used as the base material for painted vents. Custom colors are available but are subject to additional cost and lead time. Contact main office for info. The Insulated Flood Vent Series (Full Height Enclosures, Sealed Crawlspaces, Garages) x 8 RO: 16 ¼ x 8 ¼ (one CMU) 200 sq.ft of flood protection Easy to retrofit into an existing foundation 16 x 16 (aka Stackers) RO: 16 ¼ x 16 ⅜ (two CMU) 400 sq.ft of flood protection Twice as efficient as a single unit Used when adequate wall space is unavailable 32 x 16 RO: 33 x 16 ⅜ (four CMU) 800 sq.ft of flood protection Consists of two s installed side x side Excellent for commercial applications and other areas with large square footage The Insulated Flood Vent Series Ctd ½ x 8 ½ RO: 14 ½ x 8 ¾ 200 sq.ft of flood protection Designed to fit between studs spaced on 16 centers Mounting slots in each corner Great for garages, foyers, breakaway walls 16 x 8 RO: 16 x8 200 sq.ft of flood protection Ideal for retrofitting into an existing garage door Comes standard in white powder-coated paint Internal cam system keeps the flood door in place during garage door use. 14 ½ x 8 ½ RO: 14 ½ x 8 ¾ 200 sq.ft of flood protection Ideal for retrofitting into an existing garage door with smaller panels Comes standard in white powder-coated paint Internal cam system 39

40 Powder Coat Paint Options: Black, Grey, Wheat, White Give your projects a aesthetic finish look with these available stock paint options. 316 Marine Grade Stainless Steel is still used as the base material for painted vents. Custom colors are available but are subject to additional cost and lead time. Contact main office for info. What You Get Multi-Frame Options Non-Residential Projects 40

41 Projects Multi-Frame Manufacturing Pour-In-Place Vinyl Bucks Available for 16 x 8, 16 x 16, 32 x 16 Wall depths from: 7 ¼ 12 full (Nominal Sizes Available) PIP bucks come already assembled with the specified vent model ready for pour 41

42 Pour-in-Place Vinyl Bucks Works with Dual Function & Insulated Series vent models Wood bracing for installing into forms and blue plastic film on both sides to protect the vent during the pour Works with powder coat painted vents as well for even nicer finished look Trim & Sleeve Kits 16 x 8 Sizes (7-12 ½ ) (10 15 ½ ) Gives the inside of the opening a finished look Ideal for all garage and foyer applications Available for all models including custom multi-frames (not available for garage door models) Paintable Finish flanges for 570 model comes powder coat painted white standard Trim & Sleeve Kits BEFORE AFTER 42

43 Fire Dampers For use in fire rated walls UL Approved 2 and 3 hour models : 16 x : 14 ½ x 8 ½ 8 minimum wall depth required 43