Protecting Your Home

From Flood Damage

Mitigation Ideas

For Reducing Flood Loss

 

FEMA

Federal Emergency Management Agency

 


Table of Contents

Objective ........................................................................................................................................................................... i

The National Flood Insurance Program (NFIP) and Building in the Floodplain .............................................................. 1

Flood Insurance A Good Investment ............................................................................................................................. 2

Obtaining a Building Permit ............................................................................................................................................. 3

Selecting a Contractor...................................................................................................................................................... 4

Tips for Repairing a Flood-Damaged House .................................................................................................................. 5

Water-Resistant Building Materials ................................................................................................................................. 6

Mitigation Steps You Can Take ...................................................................................................................................... 7

Relocating Your House ................................................................................................................................................... 8

Elevating Your House ..................................................................................................................................................... 9

Elevating a Structure with Crawlspace Foundation ....................................................................................................... 10

Elevating a Slab-on Grade Wood Frame Structure ..................................................................................................... 11

House Elevation Regulations ........................................................................................................................................ 12

Elevating a Mobile Home ............................................................................................................................................. 13

Elevating an Electrical System ..................................................................................................................................... 14

Elevating Electric Baseboard Heaters .......................................................................................................................... 15

Elevating or Relocating the Electric Panel..................................................................................................................... 16

Elevating or Relocating the Heating Plant ...................................................................................................................... 17

Suspending a Heating System ..................................................................................................................................... 18

Elevating a Washer and Dryer ..................................................................................................................................... 19

Relocating a Washer and Dryer ................................................................................................................................... 20

Elevating or Relocating a Water Heater......................................................................................................................... 21

Elevating an Air Conditioning Compressor or Heat Pump ........................................................................................... 22

Anchoring a Fuel Tank ................................................................................................................................................. 23

Improving Interior Wall Construction ............................................................................................................................. 24

Pumping Out a Flooded Basement .............................................................................................................................. 25

Sealing Openings In Walls ........................................................................................................................................... 26

Installing an Exterior Floodwall ...................................................................................................................................... 27

Installing an Interior Floodwall ....................................................................................................................................... 28

Installing an Exterior Foundation Drainage System ...................................................................................................... 29

Installing an Interior Foundation Drainage System ....................................................................................................... 30

Sump Pumps ............................................................................................................................................................... 31

Installing a Backflow Valve ............................................................................................................................................ 32

Installing a Floor Drain Plug .......................................................................................................................................... 33

Index of Publications ................................................................................................................................................ 34-36

Objective

 

 

This manual was developed to provide a broad range of information about flood insurance, flood resistant construction techniques and water-resistant building materials. It includes illustrations depicting floodproofing methods from relocation and elevation to other less expensive alternatives.

If your home is flood-prone or flood-damaged, you owe it to yourself to be as knowledgeable as possible. If you choose to investigate some of these options or have any questions, call the Federal Emergency Management Agency (FEMA) Mitigation Office for your region at the number listed below.

 

 

 

 

Region Office

Telephone

Region Office

Telephone

1

617/223-9561

VI

817/898-5127

1I

212/225-7200

VII

816/235-7002

III

215/931-5502

VIII

303/235-7830

IV

770/220-5400

IX

415/923-7177

V

312/408-5548

X

206/487-4678

 

 

 

 

 

An index of publications is on pages 33-35. To order publications call 1-800-480-2520.

Protecting Your Home from Flood Damage, Revised 1997, 3rd Edition. Federal Emergency Management Agency.

The National Flood Insurance Program and Building in the Floodplain

What is the National Flood Insurance Program?

The National Flood Insurance Program (NFIP) is a federal program enabling property owners and renters to purchase flood insurance. It is based on an agreement between your community and the federal government. The agreement states that if your community adopts and enforces floodplain management regulations which at least meet minimum federal requirements, the federal government will make flood insurance available in your community.

How do I know if I'm in the flood­plain?

The floodplain is identified as a Special Flood Hazard Areas (SFHA) in your community's Flood Insurance Study and the accompanying Flood Insurance Rate Maps (FIRMs) published by FEMA. Your community's building officials or floodplain

administrators have these documents available for you to see. The flood level shown for these SFHA has a 1 % chance of being equaled or exceeded in any one year. That translates into a 26% chance of flooding over a typical 30-year mortgage period as compared to a 1 % chance of fire damage over the same period.

What is substantial damage?

Substantial damage is damage of any origin to a structure where the cost of restoring the structure to its before damage condition would equal or exceed fifty percent (50%) percent of its pre-disaster value.

When does it affect me?

The NFIP requires participating communities to regulate through building permits any new or substantially improved structures during non-disaster periods and to monitor and identify any substantially damaged structures as a result of a disaster within the community's floodplain areas. Participating communities adopt an ordinance requiring new buildings to be elevated at or above the Base Flood Elevation (BFE) within the identified floodplain. Non-residential buildings have the option of being dry flood proofed. Existing buildings that are substantially damaged or improved (50% or more) must be elevated or floodproofed to meet the same building code standard as a new building. When you apply for a building permit, you will be informed whether or not you are in a floodplain and what further steps are required to repair or reconstruct your building if you are within this defined area. If your building was flooded but not substantially damaged there is a wide range of inexpensive measures described in this booklet that can help you reduce future flood damage.

How high will I have to elevate?

Or floodproof?

The elevation or floodproofing requirement is based upon the BFE as indicated in the Flood Insurance Study of your community. This elevation may or may not be comparable to the last major flood. Though you had ten feet of water in your home during the last flood that may not mean you will need to elevate or floodproof to that height. Your community's building official can assist you in determining the elevation requirement for your structure.

What happens if I refuse to comply?

Participating communities in the NFIP, agree to enforce its floodplain regulations. If you do not obtain a permit and do not elevate or floodproof when required, your community could take legal action against you. This may include stopping the development, revoking the permit, imposing a fine, or withholding a certificate of occupancy. If the structure is in violation of the regulations, flood insurance premiums could be extremely costly, possibly making the structure difficult to sell. Non-compliance could jeopardize your community's continued participation in the NFIP. Federally secured loans and federal disaster assistance are restricted in communities not participating in the NFIP that contain one or more SFHA which have been identified on a FIRM or Flood Hazard Boundary Map (FHBM) for at least one year prior to the disaster declaration. Additionally, structures located in the floodplain which are not elevated or floodproofed as required pose a threat to the health and safety of the occupants.

What if I have more questions?

Your building and floodplain management officials are responsible for implementing the requirements of the local floodplain management ordinance, including the substantial damage provisions. Following a disaster declaration, the requirements pertaining to substantial damage will be presented to your community officials in detail at meetings held in various locations in the state. FEMA will work with building officials to help identify structures which may qualify as substantially damaged. In addition, FEMA will provide technical assistance to local building officials concerning the repair or reconstruction of substantially damaged structures.


Flood Insurance-A Good Investment

Flood Insurance is a good investment for property owners and renters. A Flood Insurance Policy:

 

·         Covers almost all flooding conditions.

·         Cannot be denied because of a structure's location in a floodplain or its flood history. Will provide up to $500 to cover the cost of moving your possessions to higher ground - including moving a mobile home.

·         Will cover replacement costs for primary single-family residences with full coverage.

·         Will cover both structures and contents, if insured for both.

·         Can pay a claim or partial claim within days of the disaster even without a Presidential Disaster Declaration.

·         Premium can be reduced if appropriate mitigation measures are taken.

·        Will pay to repair the flood-damaged part of your building or contents in accordance with your policy terms and conditions.

·         Has a deductible, very much like other insurance policies.

·         On policies effective June 1, 1997 and later, and under specific conditions, will pay for additional costs for retrofitting to meet LOCAL codes.

 

Flood Insurance is available only to residents of communities participating in the National Flood Insurance Program. (NFIP). For general information about flood insurance and to learn if your community is participating in the NFIP, call 1-800-427-4661.

If items such as your furnace, water heater, electrical fuse box, or other key elements were damaged consider using the mitigation techniques in this book to reduce future flood damage. If undertaken at the time you are repairing damage, or making some other major renovation to your home, these retrofitting measures do not greatly increase the cost of repairs

If there is a Presidential Declaration, other sources of funds may be available for mitigation. You may be eligible for a Minimal Home Repair grant, a Small Business Administration disaster loan, or Individual and Family Grant Program assistance. Ask those program officials about additional mitigation assistance to reduce future flood damage to the items they are helping to repair or replace. Information on these and many other funding sources is available at a Disaster Recovery Center (DRC). The location of the DRC in your area is available through the local news media-newspapers, radio and television-and through the Federal and State Community Relations personnel canvassing the disaster area.

 

Flooded?         Here's what to do.

If you experience flood damage and are covered by flood insurance, these important steps will help you when filing your flood insurance claim.

1. Save as many damaged articles as, possible. If you must throw items out, take pictures to document your losses.

2. Contact your insurance agent right away.

Once your insurance agent has your claim: 

Ø      The agent will file a Notice of Loss.

Ø      An adjuster will be assigned to your case.

Ø      Once the loss has been adjusted, a Proof of Loss will be submitted, and payment can be made. Partial payment can be made to claimants upon submission of a partial Proof of Loss .

 


Obtaining a Building Permit

Local codes generally require a building permit before you repair or floodproof your structure. Usually you need to get a permit for electrical work, plumbing and repairs for structural damage, such as foundations and exterior walls. Because your property may be located in a designated floodplain you will also want to check with the permit department before constructing any floodwalls or berms on your property. Your permit department will have maps called Flood Insurance Rate Maps (FIRMs) that will show the floodplain in your community. This area is known as the Special Flood Hazard Area (SFHA).

The National Flood Insurance Program (NFIP), and most local and state building codes require that a building in the floodplain that is substantially damaged or substantially improved be treated as new construction. The lowest floor must be elevated at or above the Base Flood Elevation (BFE). The BFE is also known as the 100-year flood level. Substantial damage means that the cost to restore your house to its "before damaged" condition would equal or exceed fifty percent (50%) of the market value of your house before the damage occurred. Substantial improvement means any reconstruction, rehabilitation, addition, or other improvement of a structure, the cost of which equals or exceeds fifty percent (50%) of the market value of the structure before the start of construction of the improvement. Combining a repair with an improvement where the total cost equals or exceeds fifty percent (50%) of the market value of your house before the damage occurred will also trigger the requirement to elevate.

If your home is substantially damaged you may have no choice but to elevate or relocate your house to meet NFIP standards. Some property owners have chosen the option of relocating their house.

Failure to follow the local building code can result in an order to stop construction, a fine, higher flood insurance rates, denial of flood insurance, or all of the above.


Selecting a Contractor

Finding a good contractor to handle difficult repair jobs or to rebuild is essential. Here are some tips to help.

Sleuthing

If you have been satisfied with work done before by a local licensed contractor, use that firm. If you haven't used a contractor before, or if you were unhappy with a previous experience, you may have to do some investigating to increase your chances of getting a good one.

·         Ask the contractor for proof of insurance. This should include a completion bond, disability and worker's compensation insurance. Improperly insured contractors may expose you to liability for accidents occurring on your property.

·         Check on the firm's reputation. Ask the local Better Business Bureau, home builders association or building trades council. They can tell you if the firm has had unanswered complaints filed against it.

·        Ask for references. Reputable contractors are willing to provide names of their previous customers. Contact some of them and ask how satisfied they were with the job and if they would hire that contractor again.

Get it in writing

No matter how well you know the contractor or how much you trust him/her, get everything related to the job in writing.

·         Get a written estimate. It should include everything you expect the contractor to do. Some contractors charge a fee for an estimate.

·         Obtain a contract. The contract should be complete and clearly state all the work, costs, and payment schedule. Never sign a blank contract or one with blank spaces. It may be worthwhile to have your attorney look it over if a lot of money is involved.

·        Ask for guarantees. Any guarantees from the contractor should be written into the contract. It should include what is guaranteed, who is responsible for the guarantee *(dealer, contractor, manufacturer) and the length of time for which the guarantee is valid.

·         Get a final contract. A signed contract is binding on both you and the contractor. Don't sign completion papers or make the final payment until the work is finished to your satisfaction and approved by your local building inspector.

Beware of Disreputable Business Activities

Areas recovering from floods are often prime targets for less-than-honest business activities. Here are some points to help safeguard against such practices

Ø      Beware of "special deals" offered after a disaster by contractors you don't know.

Ø      Beware of unknown contractors wanting to use your house as a "model home."

Ø      Do not sign any contract under pressure by a salesperson. Federal law requires a three day cooling-off period for unsolicited door-to-door sales of more than $25. If you choose to cancel such a contract within three business days of signing it, send your cancellation by registered mail.

Ø      Beware if you are asked to pay cash on the spot instead of a check made out to the contracting company. A reasonable down payment is up to 30% of the total project cost.

Ø      Your contractor should call you or a qualified observer to inspect hidden work (e.g., sewers or basement wall) before it is covered over. Most building departments must inspect electrical and plumbing lines before the walls are covered with wallboard or paneling.


Tips for Repairing a Flood Damaged Building

The most important thing -give your house plenty of time to dry! Rushing to rebuild before everything dries can cause many problems. The rule of thumb is, if it takes a week for visible moisture to disappear, it will take at least another week for unseen parts to dry. Here are some inexpensive measures you can take to make your recovery easier after the next flood.

Utilities

Electrical: Move the main breaker or fuse box and utility meters at least 12" above the Base Flood Elevation (BFE) for your house. (BFE is also referred to as the 100 year flood level). Label each circuit. If the electrical code allows, raise the electrical outlets and switches above the flood level.

Equipment: Relocate or elevate all equipment at least 12" above the BFE. If you plan to replace a flooded furnace, water heater, or air conditioner, install the new one on a higher floor. If your new air conditioner or heat pump will be outside, install it on a raised platform. An updraft furnace in a basement can be replaced with a downdraft furnace on an upper floor. Place heavy appliances on raised platforms. Make sure washers/ dryers will not vibrate off the blocks or platform during use. A one or two foot waterproof floodwall around appliances will protect them from shallow flooding.

Walls

Wash and disinfect the studs and sills if the wallboard and insulation were removed. If rebuilding, consider metal studs and sills as they are less damaged by water than wooden ones. Pressure-treated wood resists mildew and wood-eating insects but may swell when soaked. Warning: Some pressure-treated wood should not be used inside the house. It depends on the chemicals used to treat them. Ask your lumber company for consumer information that gives specific precautions.

Wallboard

If you install the wall board horizontally (four feet high), you'll only have to replace half the wall if the next flood is less than 4 feet deep.

Leave the wall open 1 inch above the sill. The baseboards will hide the gap, but all you have to do after the next flood is remove the baseboard and the wall cavity will drain freely and air will circulate better. (Not applicable if local code requires a fire wall.)

Greenboard or other moisture-resistant wallboard may be more sturdy than regular wallboard, but replacement is still often recommended as it presents the same health hazards when soaked with floodwaters.

Floors

Particle board or plywood fall apart when wet for lengthy periods. Floor joists and some wood floors regain their shape when naturally dried. Use screws or screw nails on floors and stairs to minimize warping. Completely dry subflooring before laying new flooring or carpeting. Renail, then sand or place a new underlayment for a new floor.

Paints

Completely dry the surface before painting. This may take several weeks, but paint will peel if applied over a damp surface. Coat concrete surfaces with penetrating sealer for easier future cleanup. Coat water-stained areas with shellac or commercial stain killer first or the stains will bleed through the paint. Dryproofing requires thick plastic or rubberized sheeting. Waterproofing paints do not keep out floodwaters.

Windows and Doors

When appropriate, replace flood damaged windows with vinyl or metal framed windows. Hollow core or polystyrene foam filled metal doors are water resistant. Metal in both windows and doors may rust slightly but that is easily repaired.

Water Resistant Products

Ø      Concrete, concrete block, or glazed brick

Ø      Clay, concrete, or ceramic tile

Ø      Galvanized or stainless steel nails, hurricane clips, and connectors (in areas subject to saltwater flooding)*

Ø      Indoor-outdoor carpeting, synthetic backing (not fastened down)

Ø      Vinyl, terrazzo, or rubber floor covering, with waterproof adhesives

Ø      Metal doors and window frames, vinyl window frames

Ø      Polyester-epoxy paints (Warning: do not use mildew-resistant paint indoors as it contains a toxic ingredient.)

Ø      Stone, slate, cast stone with waterproof mortar

Ø      Mastic, silicone, polyurethane formed-in-place flooring

Ø      Polystyrene plastic foam insulation D Water-resistant glue

* See Technical Bulletin 8-96, Corrosion Protection for Metal Connectors in Coastal Areas

Water-Resistant Building Materials

 

 

Marine plywood

The most water-resistant plywood; it can be used for floor and exterior-wall sheathing.

Exterior-grade plywood

Meant to resist low-level moisture, humidity. Not for water saturation conditions.

Greenboard

Manufacturers do not consider greenboard (moisture-resistant dry wall) to be a floodproofing material. It can be submerged for several hours without extensive deterioration and it is only slightly more expensive than normal plasterboard.

Rigid (closed-cell) insulation

Will not deform or lose its insulative properties when wet. Can be dried out

and reinstalled in wall or floor cavity. Use instead of fiberglass insulation.

 

Synthetic baseboards

Use instead of wood base.

 

Galvanized nails

Will not rust after being in floodwaters.  Use at all locations up to three feet above the Base Flood Elevation.

 

Metal doors and frames

Will not warp if saturated. May rust in spots, but this can be sanded out and repainted. Use at all doorways, especially exterior.

 

Metal and vinyl windows

Will not warp if saturated.

 

Sheet vinyl flooring or tile

Adheres to marine or pressure treated plywood underlayment with waterproof adhesive.

 

Indoor and outdoor carpet

Use with synthetic carpet pad. Do not permanently fasten down.

 

Galvanized drywall screws

Will not rust and allow easy removal and reassembly of interior walls. Use instead of standard drywall nails.

 

Brick, concrete

Not damaged by water saturation, but must be used in conjunction with a waterproof membrane.

 

Plastic wood

Made of recycled plastics. Waterproof and dimensionally stable. Check building code for acceptable uses.

 

Pressure-treated lumber/plywood

Relatively stable in water saturation conditions. Will not sustain heavy damage but may warp. Plywood second only to marine plywood in water-resistance. Use at all flood-levels. Moisture-resistant material below the Base Flood Elevation. (Note: If treated lumber is used, protective gloves must be worn during installation, and a protective barrier such as drywall must be placed between the treated lumber and living space.)

 

 

 

 

Building Materials to Avoid When Floodproofing

 

Fiberglass or cellulose installation
Cork or corkboard

Gasoline, motor oil, weed killer, pesticide, lye, drain dear, swimming pool and other chemicals

 

Linoleum

Particle board, plywood, chipboard, fiberboard, paperboard, strawboard, Masonite paneling

Wallboard, plasterboard, drywall, gypsum
Wallpaper

Mitigation Steps You Can Take

There is a wide range of flood protection measures for buildings that can eliminate or reduce the risk of future flood damage. Buildings can be relocated out of the floodplain area or elevated above the projected flood levels. There are also a number of relatively inexpensive flood mitigation techniques that can be used to protect specific elements of a building. This booklet provides illustrations of many flood loss reduction techniques and highlights some important basic building code requirements for building or repairing homes located in a floodplain.

  Relocate

EIevate

Other Options

Please note: Throughout this booklet you will see the terms Base Flood Elevation (BFE) and 100-Year Flood Level. These terms are interchangeable. Base Flood Elevation is the term used in most NFIP and Floodplain Management documents. The 100-year Flood Level may be more commonly known.


Relocating Your House

It is possible, and sometimes necessary, to move your house to a new location outside the floodplain. Moving your home out of the floodplain area is the surest way to protect it and yourself from flood damage, but it can be costly. You may need to purchase a new lot unless your present lot is large and has a good building location on higher ground.

 

To relocate a building, it is detached from the original foundation, placed on a heavy-duty truck bed, transported to the new site and set on a conventional foundation.

Unless there is a hidden structural defect, most homes and small commercial buildings in good structural condition can be moved with no more damage than occasional slight cracks in the plaster or wallboard joints. Single-story frame houses over a crawlspace or basement are easiest to relocate. Multi-story, slab-on-grade, and brick buildings can also be moved.

 

Moving a house is a complex operation that requires a professional house mover. Before you choose a house mover, obtain bids from several companies and contractors.

Before choosing the lowest bid be certain the contractor or mover has the experience and resources to complete the project at the quoted price. Be certain that they have liability insurance to cover the move.

Construction Steps Involvedin Building Relocation

·         Locate a new building site.

·         Check the transportation route to the new location. Is it adequate to move the house?

·    On the building site, construct a new perimeter and interior foundation to fit the existing house. Stub in new utilities to as needed.

·         Disconnect, elevate and move the house to the new location.

·         Lower and anchor, the building onto the new foundation.

·         Connect the new utilities.

Elevating Your House

Most types of homes, including wood frame, brick veneer, slab-on-grade, crawlspace or homes with basements can be elevated above floodwaters. This is a reliable floodproofing method and requires little human intervention to prepa