Region III 

November 22, 2003 
Table of Contents

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

Water Resistant Building Materials............ ....................................................................................................... ......5

Tips for Repairing a Flood-Damaged House......................................................................................................... ...6

After the Flood..Getting Back into Your HomeSafely ................................................................................. 7

Drying Out your Home After a Flood: The First Steps ........................................................................................11

Cleaning Mold, Mildew and Bacteria ......................................................................................................... 13

Mitigation Steps You Can Take .................................................................................................................. 15

Relocating Your House................................................................................................................................ 16

Elevating Your House ................................................................................................................................. 17

Elevating a Structure with Crawlspace Foundation .................................................................................. 18

Elevating a Slab-on Grade Wood Frame Structure .................................................................................. 19

House Elevation Regulations ..................................................................................................................... 20

Elevating a Mobile Home ........................................................................................................................... 21

Elevating an Electrical System.................................................................................................................... 22

Elevating Electric Baseboard Heaters ....................................................................................................... 23

Elevating or Relocating the Electric Panel ................................................................................................ 24

Elevating or Relocating the Heating Plant ................................................................................................. 25

Suspending a Heating System.................................................................................................................... 26

Elevating a Washer and Dryer ................................................................................................................... 27

Relocating a Washer and Dryer ................................................................................................................ 28

Elevating or Relocating a Water Heater .................................................................................................... 29

Elevating an Air Conditioning Compressor or Heat Pump ...............................................................................30

Anchoring a Fuel Tank ................................................................................................................................ 31

Improving Interior Wall Construction .......................................................................................................... 32

Pumping Out a Flooded Basement ................................................................................................. 33

Sealing Openings In Walls .............................................................................................................. 34

Installing an Exterior Floodwall..................................................................................................... 35

Installing an Interior Floodwall .................................................................................................... 36

Installing an Exterior Foundation Drainage system........................................................................37

Installing an Interior Foundation Drainage System ....................................................................... 38

Sump Pumps ............................................................................................................................... 39

Installing a Backflow Valve .............................................................................................................40

Installing a Floor Drain Plug .......................................................................................................... 41

Fact Sheet: Landslides and Mudflows ...........................................................................................42

Homeowner’s Landslide Guide .........................................................................................44
Protecting Your Home from Flood Damage, Revised 1997, 3rd Edition.

Federal Emergency Management Agency.

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 equalled 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.

The National Flood Insurance Program and Building in the Floodplain

1
Protecting Your Home from Flood Damage, Revised 1997, 3rd Edition.

Federal Emergency Management Agency.

Flood Insurance is a good investment ffor 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

Flood Insurance-A Good Investment

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.

2

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:

! The agent will file a Notice of Loss.

! An adjuster will be assigned to your case.

! 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 .
Protecting Your Home from Flood Damage, Revised 1997, 3rd Edition.

Federal Emergency Management Agency.

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.

3
Protecting Your Home from Flood Damage, Revised 1997, 3rd Edition.

Federal Emergency Management Agency.

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.

Selecting a Contractor

4

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:

! Beware of “special deals” offered after a disaster

by contractors you don’t know.

! Beware of unknown contractors wanting to use

your house as a “model home.”

! 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.

! 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.

! 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.
Protecting Your Home from Flood Damage, Revised 1997, 3rd Edition.

Federal Emergency Management Agency.

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.)

Water-Resistant Building Materials

6

Building Materials to Avoid

When Floodproofing

Fiberglass or cellulose installation

Cork or corkboard

Gasoline, motor oil, weed killer, pesticide, lye,

drain clear, swimming pool and other chemicals

Linoleum

Particle board, plywood, chipboard, fiberboard,

paperboard, strawboard, Masonite paneling

Wallboard, plasterboard, drywall, gypsum

Wallpaper
Protecting Your Home from Flood Damage, Revised 1997, 3rd Edition.

Federal Emergency Management Agency.

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

! Concrete, concrete block, or glazed brick

! Clay, concrete, or ceramic tile

! Galvanized or stainless steel nails, hurricane clips, and

connectors (in areas subject to saltwater flooding)*

! Indoor-outdoor carpeting, synthetic backing (not fastened

down)

! Vinyl, terrazzo, or rubber floor covering, with waterproof

adhesives

! Metal doors and window frames, vinyl window frames

! Polyester-epoxy paints (Warning: do not use

mildew-resistant paint indoors as it contains a toxic

ingredient.)

! Stone, slate, cast stone with waterproof mortar

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

! Polystyrene plastic foam insulation

! Water-resistant glue

* See Technical Bulletin 8-96, Corrosion Protection for Metal

Connectors in Coastal Areas

Tips for Repairing a Flood Damaged Building

5
After the flood...

getting back into your home safely

A building that has been damaged by rising water can be a dangerous place. This will help you know what

to look out for and how to protect yourself and your family. It will also tell you what you need to know about

cleaning up and making your home safe to live in again.

Watch out for these dangers:

Never assume that a water-damaged house is safe. Going into a building that has been flooded, even after

the water is gone, can present a wide variety of hazards that can cause injury, illness or even death. Do not

allow children in the home after the flood or while it is being cleaned, inspected or repaired.

• Electrical hazards - Do not enter a flooded or wet building if the power is on. If any

electrical circuits have gotten wet, get the power turned off at the main breaker or fuse box

and leave it off until the electrical wiring or equipment has been inspected and repaired by a

licensed electrician and approved by your local building inspector.

• Structural damage - Do not enter a building if the framing or foundation is damaged. Look

carefully before you enter. Leave immediately if shifting or unusual noises signal a possible

collapse of the building. Contact your local building inspector for a safety inspection.

• Hazardous materials - Dangerous materials that might be found in flooded homes include

pesticides, fuel oil, gasoline, chemicals and other substances that might have been brought

in or spilled by the flood. Damaged buildings may also contain asbestos and lead-based

paint, which can cause health problems during cleanup. Practically any building material

that is not obviously solid wood, metal, or glass could contain asbestos. Lead-based paint

can be found pre-1978 housing and is still used in commercial and industrial buildings.

• Injuries -Falling objects, broken or damaged building components and slick surfaces can

cause injuries, broken bones, and cuts. Lifting heavy objects can cause back and muscle

strains (see “Stay safe while you work.”).

• Biological hazards - Bacteria, viruses, molds and mildew can cause illness when you

breathe them in or take them into your body through your mouth or through a cut in the

skin. Bacteria or viruses may be left indoors by floodwater, while mold and mildew may

grow indoors after the floodwater has receded.

o Bacteria and Viruses - If you accidentally get floodwater or the dirt it leaves behind

into your mouth, you might develop gastrointestinal (digestive tract) illness.

o Mold and Mildew (Fungi) - Many building materials, furniture, carpet and other

items that stay wet for more than 24 hours will grow mold. Mold colonies are the

fuzzy or patchy white, green, brown or black growths that you will see on wallboard,

wood furniture and cabinets, clothing, wall studs, and almost any other surface.

Mold releases tiny particles into the air that can cause allergic illness like hay fever

(coughing, sneezing, eye irritation), asthma symptoms, or other respiratory illness

that can be serious. Some molds may also produce toxins that could cause other

illnesses. We are exposed to mold every day, indoors and out, but mold

contamination can be quite severe in a water-damaged building. The risk is greatest

for people with allergies or asthma, and for the very old or very young.
Stay safe while you work:

• Wear a hard hat and safety goggles when there is a danger of falling materials.

• Wear the right gloves to protect your hands from cuts or exposure to hazardous

chemicals.

• Wear rubber boots or hard-soled boots, preferably with steel toes, when working

and lifting.

• Wear a face mask. If you enter a flooded building, wear a dust mask or respirator to

reduce your exposure to mold. At your hardware or home supply store, look for a

mask with “NIOSH” approval and an N-95 rating. Both of these marks should be on

the respirator and the container. Read and follow the instructions on the mask

package. Remember that the masks are disposable and should be thrown away at

the end of the day.

• Stay alert. Accidents happen when people are tired. Take the breaks you need, and

drink plenty of fluids (bottled water, juice, soft drinks) to avoid dehydration. Never

drink alcohol when you are working in a flooded building.

• Protect yourself from bacteria and viruses. To keep from getting sick, wear

rubber gloves while working; do not eat, drink, or smoke in the house; and wash

your hands frequently with soap.

• Wet down mold. Before you touch, move, or clean moldy or mildewed materials,

wet the mold with a soapy solution from a spray bottle to prevent the mold from

getting into the air. Do this even if the material is already wet because the mold

probably won’t be wet. Remember that mold can still make you sick even after you

have sprayed disinfectants (“mold/mildew killer”) to kill it.

• Be careful lifting. To avoid back injury when lifting or handling heavy loads like

furniture or carpet, avoid lifting loads of more than 50 pounds per person.

• Get help. Before you disturb or remove materials that may be hazardous, take

precautions to prevent exposure. If there is a noticeable chemical odor and/or a

spilled container of a hazardous material in the building, ask your local health

department or fire department for help. If there is asbestos or lead paint in the

building, call NC Health Hazards Control at (919) 733-0820.

• Be prepared.If you get a cut or a puncture wound that is exposed to floodwater or

the dirt it leaves behind, see a doctor. Make sure your tetanus immunization is up-todate before you work on the house. Once immunized, adults should have a routine

“booster” every ten years..
Take these steps:

If a flooded building is to be safely reoccupied, it must be completely dry. Dirt and trash left by the flood must be

removed from building materials and furnishings. Moldy or mildewed items must be completely cleaned and

disinfected or must be thrown away. Otherwise mold and mildew will return and possibly cause health problems for

you and your family later on.

Before going back to live in your home, take the following steps:

• Get the mess out. Remove all floodwater, dirt, and debris left behind by the floodwater.

• Remove mold and mildew. Moldy or mildewed building materials should be thoroughly cleaned

and dried or removed and replaced. Any materials or furnishings that soaked up water should be

removed from the building.

• Check out the floors. Carpet and padding cannot be cleaned well enough to prevent mold and

mildew from growing. Throw them away. Take out the flooring and sub-flooring if they cannot be

completely cleaned and dried or if they have started to deteriorate. The remaining floor and/or subfloor must be dried out completely and disinfected. Make sure no moisture is trapped in or on the

sub-floor. Sub-flooring made of particleboard or plywood should be removed and replaced because

it can’t be completely dried and disinfected. Crawl spaces should also be cleaned out and dried.

• Dry out walls. Walls that were wet should be stripped to the studs and the insulation removed.

Walls must remain open to allow them to completely dry. Other wall cavities should be inspected for

visible mold growth. Any area inside a wall cavity with visible mold growth should be opened,

cleaned, decontaminated and dried. The exterior of each building (siding, etc.) will need to be

evaluated to see if any or all of the exterior materials should be removed. Plaster, brick and

concrete block walls can probably be cleaned, disinfected and completely dried. §

• Check heating and AC systems. If the heating and air-conditioning system or air ducts were

flooded, use special care. The inside parts of heating and air-conditioning systems that contacted

floodwater are hiding places for mold. If mold grows in the system, mold particles may get into the

air and make people sick. The interior components (furnace, air-conditioner cooling coils, and fans)

will need to be inspected, cleaned and decontaminated by professionals. Air registers (vents) and

diffusers should be removed, cleaned, disinfected and reinstalled. Replace lined air ducts and

ductboard that got wet. Unlined ductwork can be taken apart, washed, disinfected, dried, and put

back together. Air duct cleaning services are not very effective in cleaning flooded air ducts and are

only useful on bare sheet-metal ducts.

• Salvage what you can. Personal property and furnishings that are moist or wet 24 hours after

floodwater recedes will have mold growing in or on them. Clothing and linens may be salvaged by

washing with chlorine bleach and detergent, or sent to commercial laundries or dry cleaners.

Upholstered furniture, mattresses, and furniture made of particleboard or wafer board should be

thrown away. Get information on saving valuable papers, books, and photographs from the

American Red Cross.

• Remove contaminants. Make sure that any chemical contamination and hazardous materials have

been removed from the building. For proper disposal, contact your local waste disposal service.

Make sure that all parts of the building are dry before rebuilding or repairing. Mold will grow on

replacement materials if the studs, subfloor or other building parts are not completely dry. The

structure should be tested with a moisture meter before you start replacing the damaged parts of

your home.
Clean and dry the right way:

Nonporous materials (materials that don’t soak up water) and furnishings and other

surfaces should be thoroughly cleaned, disinfected and allowed to dry completely. First,

scrub all surfaces with soap and water and rinse well. (Scrubbing removes mold, mold

spores, and the dirt that mold and mildew can grow on.) Then, disinfect everything. Liquid

chlorine bleach should be used to disinfect and kill any remaining mold and mildew. Follow

the instructions on the label and let the bleach solution remain on the surface for at least 15

minutes before rinsing and drying. After cleaning and disinfecting, you must completely dry

each item or mold and mildew will return. To speed drying, keep fresh air circulating.

You can get the document from your local health department or on the Internet at www.cdc.gov/niosh/

flood.htm.

For more information about flood cleanup and removing mold, ask your health department or a Red Cross

volunteer for a copy of the Red Cross/FEMA Document: “Repairing Your Flooded Home,” or look on the

Internet at http://www.fema.gov/library/repfhm.pdf.

The most important thing you can do to protect yourself is to use common sense and be aware of safety

and health risks. Do not enter a building that is clearly unsafe. If you have questions or need assistance,

contact your local health department or building inspections office.
DRYING OUT YOUR HOME AFTER A

FLOOD: THE FIRST STEPS

Floodwaters affect a house in 3 ways:

• The water damages materials. Wallboard will disintegrate if it stays wet too long; wood can

swell, warp, or rot; electrical parts can short out, malfunction, and cause fires or shock.

• Mud, silt, and unknown contaminants in the water not only get everything dirty; they are also

unhealthy.

• Dampness promotes the growth of mildew, a mold or fungus that can grow on everything.

The following steps will help you get started in dealing with these problems. Please do the steps in

order.

Lower the Humidity

Everything will dry more quickly and clean more easily if you can reduce the humidity and stop the

rot and mildew.

Open up the house. If the humidity outside is lower than it is indoors, and if the weather permits,

open all the doors and windows to exchange the moist indoor air for drier outdoor air. When

temperatures drop at night, an open house is warmer and will draw moisture indoors. At night, and at

other times when the humidity is higher outdoors, close up the house.

Open closet and cabinet doors. Remove drawers to let air circulate. Drawers may stick because of

swelling. Don’t try to force them. Help them dry by opening up the back of the cabinet so air can get

into it.

Use fans. Fans help to move the air and dry out your home. Do not use central air conditioning or the

furnace blower if the ducts were under water. They will blow out dirty air that might contain

contaminants. Clean or hose out the ducts first.

Run dehumidifiers to reduce the moisture, especially in closed-up areas.

Use desiccants. Desiccants are materials that absorb moisture and can be used in drying closets or

other closed areas where air cannot move through. Desiccants like those listed below are usually

available at hardware, grocery, or drug stores.

• Chemical dehumidifier packs used for drying boats and damp closets.

• Cat litter made of clay.

• Calcium chloride pellets (used to melt ice in the winter). Hang pellets in a pillow case, nylon

stocking, or other porous bag. Put a bucket underneath to catch dripping water. Close the closet or

area being dried. Be careful. Calcium chloride can burn your skin. It will also make the air salty,

so do not use this product near computers or other delicate equipment.

Call a contractor. There are contractors who specialize in drying out flooded buildings. Look in the

yellow pages under Fire and Water Damage Restoration or under Dehumidifying. Be careful about

contractors who inflate prices after a disaster.

Be patient. Drying your house could take several weeks. Until your house is reasonably dry, damage

caused by mildew and decay will continue. The musty odor will stay forever if the house is not dried

out well.
Sort Contents and Discard Debris

You have 3 types of contents. They should go to 3 different places:

• Items you want to save

• Items to be thrown out

• Garbage

Things you want to save

Move things you want to save to a safe, dry place, such as the second story or outside. The

longer they sit in water, the more damaged they become. Don’t leave wood furniture in the sun

because it will warp as it dries.

Things you don’t want to save

Put things you don’t want to save outside to dry until the adjuster comes to confirm your

losses. Take pictures or videotapes and list each item for the record.

Garbage

Get rid of food and anything else that could spoil or go bad immediately. Don’t let garbage

build up. Garbage piles will cause yet another health hazard by attracting animals and insects. If your

insurance adjuster has not come, tell your agent or adjuster that you need to get rid of potential health

hazards. That person will tell you how to make sure that your losses are covered. Then throw the

stuff out, preferably in sealed plastic garbage bags. Dispose of discarded items properly. Do not burn

or bury them. There will usually be more frequent garbage pickups after a flood. Your local

newspapers or local TV and radio stations will have announcements about trash pickup schedules

and drop-off sites.
Mold, mildew and bacteria are common following

floods and other water damage. If unchecked they

can lead to sanitation and health problems. The

walls, floors, closets, shelves, contents-every flooded

part of your house-should be thoroughly washed and

disinfected.

In most cases, household cleaning products will do

the job if you use them correctly. Check the label on

the products to see how much to use. Some products

shouldn’t be used on certain materials; the label will

tell you that. Apply cleaner and give it time to work

before you mop or sponge it up. Follow directions

and all safety precautions on the container. After

cleaning a room or item, go over it again with a

disinfectant to kill the germs and smell left by the

floodwaters.

Cleaning tips: Tackle one room at a time. A twobucket approach is mot efficient: use one bucket for

rinse water and the other for the cleaner. Rinse out

your sponge, mop, or cleaning cloth in the rinse

bucket. Wring it as dry as possible and keep it rolled

up tightly as you put it in the cleaner bucket. Let it

unroll to absorb the cleaner. Using two buckets

keeps most of the dirty rinse water out of your

cleaning solution. Replace the rinse water

frequently.

Walls: Start cleaning a wall at the bottom or where

the worst damage was. If you did not have to

remove the wallboard or plaster, you may find that

the wallboard or plaster won’t come clean and you

will want to replace it rather than clean it. If you

have removed the wallboard or plaster, wash the

studs and sills and disinfect them.

Furniture: Wood alcohol or turpentine applied with

a cotton ball may remove white mildew spots on

wood. Cream wood restorers and lanolin will help

restore good wooden furniture.

 Upholstered furniture soaks up contaminants

from floodwaters and should be cleaned only by a

professional. This is also true of carpets and

bedding. Unless the piece is an antique or very

valuable, upholstered furniture soaked by

floodwaters should probably be thrown out.

Cleaners

1st choice: Non-sudsing household cleaners

2nd choice: Laundry soap or detergent

Disinfectants

1st choice: Commercial disinfectants or sanitizers,

such as the quaternary, phenolic, or pine oil based

ones. (Check labels for the contents).

2nd choice: 1⁄4 cup (2 ounces) of laundry bleach for

one gallon of water.

Mildew Removers

1st choice: Commercial mildew removers or

mildewicides

2nd choice: Washing soda or tri-sodium phosphate

(available at grocery or paint stores). Use five

tablespoons per gallon of water.

3rd choice: 1⁄4 cup (2 ounces) of laundry bleach for

one gallon of water. See below on using bleach.

Bleach

Liquid chlorine bleach, such as Clorox or Purex

bleach, can do a variety of flood clean up jobs.

Make sure that 5.25% sodium hypochlorite is the

only active ingredient. Bleach that has a scent added

to improve its smell is available. Scented bleach is

fine for cleanup jobs, but don’t use it to treat

drinking water. Don’t use dry bleach or any beach

that does not contain chlorine. Be careful of fumes

and wear rubber gloves. Read the safety instructions

on the label. Do not mix bleach with other

household chemical products, especially ammonia or

toilet bowl cleaner; the chemical reaction can create

a poisonous gas. Do not use bleach on aluminum or

linoleum.

Cleaning Mold, Mildew and Bacteria

Cleaning Supplies Checklist

Brooms, Mops, Brushes, Sponges

Buckets, Hose Cleaner

Rubber Gloves Lubricating Oil

Rags Trash bags

Disinfecants Hair Dryer
Clothing and Linens: Even if your washing machine

did not get wet, do use it until you know that the

water is safe enough to drink and that your sewer

line works. Before you wash clothes in the washing

machine, run the machine through one full cycle. Be

sure to use hot water and a disinfectant or sanitizer.

Take clothes and linens outdoors and shake out dried

mud or dirt before you wash them. To prevent a

drain clog, hose off muddy items to remove all dirt

before you put them in the washer. Check the labels

on clothes and linens, and wash them in detergent

and warm water if possible. Adding chlorine bleach

to the wash cycle will remove most mildew and will

sanitize the clothing, but bleach fades some fabrics

and damages other fabrics. You can buy other

sanitizers, such as pine oil cleaners, at the grocery

store to sanitize fabrics that cannot be bleached.

 If the label says “Dry Clean Only,” shake out

loose dirt and take the item to a professional cleaner.

If you want to clean leather yourself, wash the mud

off and dry the leather slowly away from heat or

sunlight.

Appliances: There is an unexpected danger of shock

with some electrical appliances such as TV sets and

radios. Certain internal parts store electricity even

when the appliance is unplugged. Check the back

for a warning label. Appliances with such labels will

need professional cleaning.

 You will need appliances such as the washing

machine, dryer, dishwasher, and vacuum cleaner to

help clean your house and its contents. The motors

or heating elements can usually be cleaned. If you

cannot wait for a professional cleaning job, unplug,

disassemble, and hose off the appliances thoroughly

(with hot water, if possible). Then clean and

disinfect them, but do not use detergents.

 Clean and disinfect dishwashers, washing

machined, and dryers only with water that has been

declared safe for drinking. Make sure the sewer line

is working before you start a dishwasher or washing

machine.

 You can speed up the drying process for motors

and parts by using a blow dryer or a moisture

displacement spray. Moisture displacement sprays,

such as electronics parts cleaners or WD-40

lubricating and penetrating oil can also stop rust and

corrosion until the appliance can be disassembled

and cleaned. One word of caution: The spray is

flammable. Read and follow label instructions and

precautions.

 Moving parts such as motors and pulleys will

need oil or grease. Contacts and electrical switches

can be cleaned with moisture displacement spray or

an aerosol contact cleaner available at electronics or

auto parts stores. Allow a motor to run for 30

minutes with no load before using it.

 Watch for stripped or damaged insulation around

wires. Be sure all appliances are properly grounded.

Appliances that must be grounded have a round third

prong or a grounding wire on their plug.

 Refrigerators, freezers and ovens are more

complicated. They may have foam insulation and

sealed components that suffered little water damage.

But these appliances hold food, and so they should

be cleaned, disinfected and checked by a

professional or replaced.

Kitchen items: Throw out soft plastic and porous

items that probably absorbed whatever the

floodwaters carried in. Floodwaters are

contaminated, so you may want to wash dishes by

hand in a disinfectant. Air dry the disinfected

dishes; do no use a dishtowel. The dishwasher

should also be used only after you know your water

is safe to drink and your sewer line works. Clean

and disinfect it first. Then use a hot setting to wash

your pots, pans, dishes, and utensils. (If you have an

energy saving setting, do not use it.)

Food: Throw out any food that has been touched by

floodwaters. Even food in tin cans should be

discarded if the cans got wet during the flood

because there is no way to be absolutely certain the

food inside is safe. Do not keep food in bottles or

jars with bottle caps or screw on lids-they do not

keep out floodwaters. The U.S. Department of

Agriculture operates a food safety hot line.

Professional home economists can answer your

questions about whether to keep or discard food.

 To reach the food safety hotline call 1-800-535-

4555 between 10:00 am and 4:00 pm, Eastern Time,

Monday through Friday.

For addition information, see the booklets

Repairing Your Flooded Home and Cleaning

Up, which are available at the Disaster

Recovery Centers. Repairing Your Flooded

Home is also available in .PDF format on the

internet at: http://www.fema.gov/library.
Protecting Your Home from Flood Damage, Revised 1997, 3rd Edition.

Federal Emergency Management Agency. 7

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.

Please note: Throughout this booklet you will see the terms Base Flood Elevation (BFE) and 100-Year Flood Level. These

terms are interchangable. Base Flood Elevation is the term used in most NFIP and Floodplain Management documents. The

100-year Flood Level may be more commonly known.

✓

❒✓

❒✓

❒

Relocate

Elevate

Other Options
Protecting Your Home from Flood Damage, Revised 1997, 3rd Edition.

Federal Emergency Management Agency.

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.

Relocating Your House

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.

8

Construction Steps Involved

 in 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.
Protecting Your Home from Flood Damage, Revised 1997, 3rd Edition.

Federal Emergency Management Agency.

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 prepare for a flood. Elevation

requirements vary with local codes and ordinances but the new first floor elevation should be at or above the 100-year-flood

level. You may wish to exceed the code requirements. Some buildings may be elevated high enough for the new lower level

to serve as a garage. All elevated homes need new stairs and porches built to the new height. Elevating a home requires the

services of plumbers, electricians, house movers and contractors. Because the new foundation will be in the floodwaters, it is

important that it be structurally designed to withstand lateral (sideways) forces like fast-flowing currents and the impact of

waterborne debris. A structural engineer can help you design your new foundation and obtain a permit from your building

department.

Basic Steps in Elevating a Building:

! Have appropriate professionals disconnect all utilities.

! Hire a professional house mover to disconnect your house from

the existing foundation, jack it up to the new height and provide

a temporary foundation.

! Have the utilities temporarily reconnected so the house is liveable

while foundation work is done.

! Build a temporary access stair to meet the new height.

! Build a new, permanent foundation.

! Have the house mover lower the house onto the new foundation

and connect them together with anchor bolts.

! Have the utilities permanently reconnected.

! Build a new, permanent access stair and landing

9

Figure 1: I-beams are placed under lifting points perpendicular to floor joists with a second set beneath for uniform

lifting.

hydraulic

 jack

Figure 2: The house is detached from the foundation, lifted by jacks, and

a new foundation built beneath it.

new foundation

Figure 3: For houses elevated on posts or columns, encase the posts in concrete and provide lateral bracing.

lateral

bracing

concrete encasement

concrete

 post or

column
Protecting Your Home from Flood Damage, Revised 1997, 3rd Edition.

Federal Emergency Management Agency.

Elevating a Structure with Crawlspace Foundation

10
Protecting Your Home from Flood Damage, Revised 1997, 3rd Edition.

Federal Emergency Management Agency.

Elevating a Slab-on-Grade Wood Frame Structure

11
Protecting Your Home from Flood Damage, Revised 1997, 3rd Edition.

Federal Emergency Management Agency.

House Elevation Regulations

Substantial Damage

Substantial damage is structure damage from any cause where the cost of restoring the structure to its “before damage”

condition would equal or exceed fifty (50) percent of its pre-disaster value.

NFIP Housing Elevation Regulations

Within communities participating in the NFIP, certain requirements apply when building a new home, when substantial

damage has occurred to an existing home, or when substantial improvements to an existing home are planned.

! In A-Zones, the top of a building’s lowest floor, including basement, must be elevated to the Base Flood

Elevation (BFE) plus any additional height above the BFE your community may require.

A Zones - Riverine and coastal areas subject to flooding with waves less than 3 ft. in height.

! In V-Zones, the lowest portion of the horizontal structural members supporting the lowest floor must be

elevated to the BFE plus any additional height above the BFE your community may require.

V-Zones - Areas adjacent to the beach subject to unusually high tides with wind driven, velocity waves of

 three ft. or more.

! Building materials located below the BFE, must be resistant to flood damage.

! Any enclosed area below the BFE must be constructed to prevent flotation, collapse, and lateral (sideways)

movement of the structure. In A-Zones, exterior walls must have sufficient openings, or be designed, to allow

the equalization of the hydrostatic forces on the walls. For V-Zones only, the walls of the enclosed area must

be constructed to breakaway. Solid breakaway walls are not an integral part of the structural support of a

building and are intended through their design and construction to collapse under specific lateral loading

forces, without causing damage to the elevated portion of the building or supporting foundation. An area so

enclosed is not secure against forcible entry.

! Construction of basements (enclosures with floor levels completely below ground level) is not permitted

below the BFE.

! All machinery and equipment servicing the building must be elevated to or above the BFE or designed to

prevent water from entering or accumulating during flooding. Such machinery/equipment includes but is not

limited to furnaces, heat pumps, hot water heaters, air-conditioners, washers, dryers, refrigerators and similar

appliances, elevator lift machinery, and electrical junction and circuit breaker boxes.

! All space designed for human habitation, including bedrooms, bathrooms, kitchen, dining, living, family and

recreation rooms, must be elevated to or above the BFE.

! Uses permitted in spaces below the BFE are restricted to vehicular parking, limited storage, and building

access (stairs, stairwells and elevator shafts).

12
Protecting Your Home from Flood Damage, Revised 1997, 3rd Edition.

Federal Emergency Management Agency.

Elevating a Mobile Home

Foundations, cross bracing and tiedowns are the three basics of the proper elevation and anchoring of a manufactured home.

Each is essential for a safe and secure mobile home installation.

Foundations

A poured concrete footing, reinforced with rebar, gives maximum

stability. Extend rebar from the footing and up into the steel

reinforce concrete or concrete block pier. Solidly fill each

concrete block with concrete. Cast threaded anchor bolts into

the top of each pier to anchor the mobile home frame to the

foundation. Posts attached to piers with special connectors cast

into the concrete are also effective. In areas with soft ground,

post foundations may be able to achieve the required foundation

strength. Drive posts into the ground down to a rock foundation,

or to a depth specified by an engineer. Backfill posts with concrete

for maximum strength.

Manufactured Home Showing Cross Bracing and Foundation

13

Cross-bracing

Diagonal bracing reduces foundation twisting and the potential

of collapse in flooding or high winds. Brace foundation posts

with 2-inch nominal lumber bolted to the piers, or with steel rods

fitted through drilled holes, fastened with nuts and tightened

with turnbuckles.

Post Backfilled with Concrete Post Anchoring

Large Pier Design Fill block cells with concrete

Tie-down straps

Tie-down straps are used at the base of the manufactured

home and can be tied over the top. The most common failure

is pullout of the ground anchor. For maximum pullout

resistance, cast the anchor into a concrete deadman.

Tie Down Straps Tie Components Concrete & Deadman Anchor

Note: In order for manufactured/mobile home owners located in Special Flood Hazard Areas to be eligible for NFIP flood insurance,

their manufactured/mobile home must be able to resist floatation, collapse or lateral movement either by: 1.) Over the top or frame

ties to ground anchors; 2.) or in accordance with the manufacturer’s specifications; 3.) or in compliance with the community’s flood

plain management requirements unless it is a manufactured/mobile home on a permanent foundation continuously insured by the

NFIP on the same site since 9/30/82. (Source: NFIP Standard Flood Insurance Policy, Article 6, Paragraph H)

Diagonal Bracing with Wood Diagonal Bracing with Steel Rods
Protecting Your Home from Flood Damage, Revised 1997, 3rd Edition.

Federal Emergency Management Agency.

Elevating an Electrical System

The surest way to protect your valuable electrical system is to keep it from getting wet. When rebuilding after a flood,

or repairing by wet floodproofing, move all wiring at least one foot above the 100-year flood level. All outlets, switches,

light sockets and junction boxes, as well as the main breaker or fuse box and electric motors, should be out of danger

of getting wet.

Run wires overhead. If a wire has to run into the areas that could get wet use a wire rated for underground use. No

wire should end in the flood zone and all junctions should be in approved junction boxes. If a wire has to terminate

below the 100-year flood level it should be specially marked in the panel box and turned off at the time of a flood

warning.

Change all outlets to ground fault interrupters (GFI). Be sure all electrical wiring is done by a licensed electrician and

approved by the local building department.

14

Certain repairs are not permitted for substantially damaged

buildings. Check with your local building official or floodplain

administrator before beginning repairs.
Protecting Your Home from Flood Damage, Revised 1997, 3rd Edition.

Federal Emergency Management Agency.

Elevating Electric Baseboard Heaters

Protect your electric baseboard heater system by elevating it at least one foot above the 100-year flood level. Use

waterproof wall construction materials and techniques for the wall area below the baseboard units.

15

Certain repairs are not permitted for substantially damaged

buildings. Check with your local building official or floodplain

administrator before beginning repairs.
Protecting Your Home from Flood Damage, Revised 1997, 3rd Edition.

Federal Emergency Management Agency.

Elevating or Relocating the Electric Panel

Elevate or relocate your electric panel above the 100-year flood level to help prevent damage. All relevant permits

must be obtained before work begins, and all work must conform to state and local building codes.

Elevate

Relocate electric panel to a recommended minimum 12” safety margin above the base flood elevation or the highest

known flood level if you are outside of any known flood zone. The maximum panel height is regulated by code.

Relocate

Relocate the electric panel to available space above the first floor to protect it from flooding.

16

Certain repairs are not

permitted for

substantially damaged

buildings. Check with

your local building

official or floodplain

administrator before

beginning repairs.
Protecting Your Home from Flood Damage, Revised 1997, 3rd Edition.

Federal Emergency Management Agency.

Elevating or Relocating the Heating Plant

When relocating or raising the heating plant be sure it will have a 12 inch safety margin above the 100-year flood level.

If the existing ductwork for your furnace is below the 100-year flood level (e.g. inside a slab or crawlspace beneath the

home) it should be relocated so that it distributes heat from at least one foot above the 100-year flood level. Your local

building department can help you determine your 100-year flood level. If you locate the furnace on an upper floor or

attic it will require the installation of a “downdraft” furnace, which is slightly different from a standard model. If you are

replacing your furnace ask your supplier for information on a downdraft system.

17

Certain repairs are not permitted for substantially damaged

buildings. Check with your local building official or floodplain

administrator before beginning repairs.
Protecting Your Home from Flood Damage, Revised 1997, 3rd Edition.

Federal Emergency Management Agency.

Suspending a Heating System

Suspend the heating system with a safety margin of at least 12” above the 100-year flood level and in

a manner that conforms to the manufacturer’s specifications and all applicable state and local building

codes.

18

Certain repairs are not permitted for substantially damaged

buildings. Check with your local building official or floodplain

administrator before beginning repairs.
Protecting Your Home from Flood Damage, Revised 1997, 3rd Edition.

Federal Emergency Management Agency.

Elevating a Washer and Dryer

Elevate your washer and dryer on a masonry or pressure treated lumber base to at least a 12” safety

margin above the 100-year flood level.

19

Certain repairs are not permitted for substantially damaged

buildings. Check with your local building official or floodplain

administrator before beginning repairs.
Protecting Your Home from Flood Damage, Revised 1997, 3rd Edition.

Federal Emergency Management Agency.

Relocating a Washer and Dryer

To protect them from flood damage, relocate washer and dryer to a floor at least 12 inches

above the base flood elevation.

20

Certain repairs are not permitted for substantially damaged

buildings. Check with your local building official or floodplain

administrator before beginning repairs.
Protecting Your Home from Flood Damage, Revised 1997, 3rd Edition.

Federal Emergency Management Agency.

Elevating or Relocating a Water Heater

When relocating or raising the water heater be sure that it will be at least 12 inches above the 100-year

flood level. Consult your local building department for details.

21

Certain repairs are not permitted for substantially damaged

buildings. Check with your local building official or floodplain

administrator before beginning repairs.
Protecting Your Home from Flood Damage, Revised 1997, 3rd Edition.

Federal Emergency Management Agency.

Elevating an Air Conditioning Compressor

 or Heat Pump

22

Certain repairs are not permitted for substantially damaged

buildings. Check with your local building official or floodplain

administrator before beginning repairs.
Protecting Your Home from Flood Damage, Revised 1997, 3rd Edition.

Federal Emergency Management Agency.

Anchoring a Fuel Tank

Unanchored fuel tanks can tip over or float. Escaping fuel may result in spills and fires. To prevent

this, anchor your fuel tank. Use non-corrosive metal structural supports and fasteners. The type of

anchorage, including slab dimensions, will vary depending on the size of the tank. Keep the

fuel tank topped off to increase the tank’s weight and to reduce it’s tendency to float.

 Note:

! Check with the fuel tank manufacturer

for recommendations on anchoring.

! Be sure all work done conforms to state

and local building codes.

! For rented tanks, check with the fuel

supplier before making any modifications to the tank.

23
Protecting Your Home from Flood Damage, Revised 1997, 3rd Edition.

Federal Emergency Management Agency.

Improving Interior Wall Construction

24

Certain repairs are not permitted for substantially damaged

buildings. Check with your local building official or floodplain

administrator before beginning repairs.
Protecting Your Home from Flood Damage, Revised 1997, 3rd Edition.

Federal Emergency Management Agency.

Pumping Out a Flooded Basement

If your basement is flooded, don’t rush to pump it out.

Water in the ground outside your house is pushing hard

against the outside of your basement walls; and the water

inside your basement is pushing right back. If you drain

your basement faster than the water outside drains out of

the ground, the outside pressure will be greater than the

inside pressure. This unequal pressure may cause the

floor to crack then buckle and the wall to crack and possibly

collapse.

How to Safely Pump Water

Out of Your Basement

! Never go into a flooded basement unless you are sure the electricity is off.

! Start pumping the water out of the basement when floodwaters no longer cover the ground.

! Gasoline engines create deadly carbon monoxide exhaust fumes. Don’t use gasoline-powered pumps or generators

indoors.

! Pump the water level down 2 to 3 feet. Mark the level, and wait overnight.

! Check the water level the next day. If the water level went back up over your mark, it is still too early to drain your

basement. Wait 24 hours, then pump the water down 2 to 3 feet again. Mark the level and check it the next day.

! When the water stops rising, pump down another 2 to 3 feet and wait overnight. Repeat steps 4 and 5 until all water is

pumped out of the basement.

What to Do After Draining Your Basement

! Disinfect the floors and walls to remove bacteria left from the floodwaters.

! Before turning the power back on, check any electrical service that may have been damaged. Replace any wiring,

switches, outlets that were wet during the flood.

! Remove heating and air conditioning vents or registers as soon as possible and hose out the ductwork. Flooded ducts

contain mud and bacteria.

! Check your water system for loose pipes and leaks.

! Check your water supply to be certain it is not contaminated.

! Check all other utilities and drains for damage from the floodwaters.

25

Figure 1: Water in the basement equalizes pressure from

water outside.

Figure 2: Without water in the

basement, pressure from

groundwater can cause the floor

to crack and the walls to collapse.
Protecting Your Home from Flood Damage, Revised 1997, 3rd Edition.

Federal Emergency Management Agency.

If your house is being flooded by flowing waters entering through windows, doors or other openings, you can temporarily seal

those openings to keep the water out.

Make or purchase metal or wooden shields to fit the openings. Secure the shields to the openings with bolts or slide them into

special positioning channels. Seal the shields to the opening with a special rubber gasket or a bead of caulking to make them

water tight. Also, sandbags can be stacked in doorways or window wells and vents to make the openings water resistant.

Note: Shield height generally should not exceed 1 1/2 feet above ground level.

Exterior water deeper than 1 1/2 feet could push the walls in if there is no water inside to push back with equal force.

Figure 1: Bolt-on flood shield Figure 2: Removable window cover

Sealing Openings In Walls

26
Protecting Your Home from Flood Damage, Revised 1997, 3rd Edition.

Federal Emergency Management Agency.

An exterior floodwall can protect a window well or stair against low level flooding. Constructed of concrete or masonry the walls

should be supported by and securely tied into a footing so they will not be undercut by scouring. Understanding your particular

flood situation and soil conditions is important in order to properly evaluate if a flood wall is the right solution for you. Flood walls

are not effective when the ground becomes saturated.

Construct a watertight flood wall around the perimeter of the opening. The wall should not exceed three feet in height and must

be constructed of steel reinforced poured concrete or steel reinforced concrete masonry units to prevent failure under flood

conditions. Install a proper footing and anchor the floodwall to existing walls. Install a watertight, spring-loaded steel access

door and watertight gaskets on sides and bottom of frame at any necessary opening. Be sure all work conforms to State and

local building codes.

Installing an Exterior Floodwall

27
Protecting Your Home from Flood Damage, Revised 1997, 3rd Edition.

Federal Emergency Management Agency.

Installing an Interior Floodwall

An interior flood wall can protect against low level flooding. The wall must enclose the utilities and be at least one foot

above the 100 year flood elevation. To resist the pressure of the floodwaters, construct the wall of either steel

reinforced concrete blocks or steel reinforced poured concrete. Connect the new wall to the existing basement wall

and floor with properly embedded reinforcing steel. For best protection, do not install gates which open into the

enclosure.

28
Protecting Your Home from Flood Damage, Revised 1997, 3rd Edition.

Federal Emergency Management Agency.

All houses need a well-developed drain system to collect and carry away groundwaters. This means installing drains around all

footings. Use perforated pipe surrounded by a filter fabric and covered with rounded drain rock to drain water that seeps

through the ground. These drains should slope to a low point from which a single line should carry the water away from the

house, either to a drain line in the street or to a drywell on your property. Do not drain water toward a hillside. Doing so may

create concentrations of water that can trigger landslides.

A 4” deep bed of gravel under the lab should allow water to run to a central collection pint where there is a sump pump with a

continuous power source. If you have a lot of water under the slab, you may need to install perforated pipe drain lines to carry

the water to the sump pump.

As with other retrofitting systems, a sealed house will usually need a sewer backflow protection device.

Exterior Foundation Drain System

Installing an Exterior Foundation Drainage System

29

Certain repairs are not permitted for substantially damaged

buildings. Check with your local building official or floodplain

administrator before beginning repairs.
Protecting Your Home from Flood Damage, Revised 1997, 3rd Edition.

Federal Emergency Management Agency.

Some homes need a basement foundation drain system to collect and carry away groundwater. This may involve cutting the

floor slab, excavating a trench and installing drains along the inside perimeter of all footings. These drains should slope to a low

point from which a single line can carry the water away from the house, either to a drain line in the street or a drywell on your

property. Do not drain water toward a hillside. Doing so may create concentrations of water that can trigger landslides.

The basement drainage retrofit depicted below is a simple, generic system utilizing perforated drain pipe, wrapped in filter

fabric, and imbedded in rounded drain rock. Other, more sophisticated systems, some of which are patented, are available to

correct serious basement drainage problems. Consult an architect, engineer or licensed specialty contractor for specific

information and recommendations regarding system alternatives.

Interior Basement Drain System

Installing an Interior Foundation Drainage System

30

Certain repairs are not permitted for substantially damaged

buildings. Check with your local building official or floodplain

administrator before beginning repairs.
Protecting Your Home from Flood Damage, Revised 1997, 3rd Edition.

Federal Emergency Management Agency.

Note: Removal of water from a basement where there is flooding or high groundwater may cause

the basement walls to collapse. Basements should not be pumped out until the floodwaters subside.

31

Sump Pumps

Sump: A hole designed to collect water.

Sump Pump: A pump used to remove water from basements and other low areas.

A sump consists of a perforated liner set in a hole lined with coarse stone. The stone helps collect water and filter out fine particles.

A filter cloth may extend the life of the sump by preventing if from silting up. Perforated water-collection pipes draining to the sump

make it more effective. In some homes, all lower level waste water is pumped up and

out by a sump pump.

A sump pump is usually either the submersible

type with a motor and impeller under water, or

the pedestal type with the impeller under water

and motor on top. Both types have an automatic

switch. Both types will work until the electricity is

shorted by the water. With the submersible type,

this happens at the end of the electrical supply

wire. With the pedestal type, it happens when the

water reaches the motor on top of the pedestal.

Both types should have a one-way valve that will

not allow the water to flow back into the discharge

hose or pipe.

Caution!

Electricity and water are a hazardous combination. The sump pump must be wired into a grounded

receptacle that only allows one plug. A second nearby outlet should be equipped with a ground fault

circuit interrupter (GFCI). This second outlet should be handy so that people working near the sump

pump will not be tempted to unplug it to use the outlet, thereby placing themselves in danger.

If you drain your basement too quickly, the pressure outside the walls will be greater than the

pressure inside the walls and that may make the walls and floor crack and collapse, causing

serious damage.

To avoid this situation, follow these steps when you pump the water out of your basement:

Never go into a flooded basement unless you are sure the electricity is off.

Start pumping the water out of the basement when floodwaters no longer cover the ground.

Gasoline engines create deadly carbon monoxide exhaust fumes. Don’t use gasoline-powered

pumps or generators indoors.

Pump the water level down 2 to 3 feet. Mark the level and wait overnight. Check the water level the next day. If the water went back up (it

covered your mark), it is still too early to drain your basement. Wait 24 hours. Then pump the water down 2 or 3 feet again. Check the level

the next day.

When the water stops going back up, pump down another 2 to 3 feet and wait overnight. Repeat steps 4 and 5 until all water is pumped out

of the basement.

Figure 1: Pedestal Pump Figure 2: Submersible Pump
Protecting Your Home from Flood Damage, Revised 1997, 3rd Edition.

Federal Emergency Management Agency.

Installing a Backflow Valve

The sewage/septic system is designed to remove sewage from a house. If flood water enters the

system, the sewage can backup and enter your home. To help prevent this, install a backflow valve in

the sewer line. The backflow valve is opened by the flow of sewage exiting your home, but closes

when the flow reverses preventing sewage from backing up into your home. Check with your local

building official for permitting and code requirements. It is recommended that this work be done by a

qualified, licensed contractor.

32

Certain repairs are not permitted for substantially damaged

buildings. Check with your local building official or floodplain

administrator before beginning repairs.
Protecting Your Home from Flood Damage, Revised 1997, 3rd Edition.

Federal Emergency Management Agency.

The easiest way to stop sewer backup is to plug the opening where the backup can first enter the house. The sanitary system’s

lowest opening in the house is the floor drain. Commercial plugs are available that can be placed in the floor drain below the

grate. Bolts on metal end pieces are tightened, causing a rubber gasket to expand and seal the plug in the pipe.

A plug not only stops water from entering the house but it prevents it from leaving the house as well. Because of this, it may be

best to put the plug in place only during heavy rains.

You may install a plug with a float. The float allows water to drain out of the basement. When the sewer backs up, the float rises

and plugs the drain. A float plug permanently installed will not interfere with the floor drain’s normal operation.

Caution

! Float plugs may be blocked open by even small amounts of debris.

! Floor drain plugs do not stop backup from coming out of the next lowest opening, for example a laundry tub or

basement toilet.

! In older houses the sewer lines under the basement floor may be clay tile. A build up of water pressure can

damage the sewer lines.

Installing a Floor Drain Plug

33

Certain repairs are not permitted for substantially damaged

buildings. Check with your local building official or floodplain

administrator before beginning repairs.
Fact Sheet: Landslides and Mudflows

Landslide and mudflows usually strike without warning. The force of rocks, soil, or other debris

moving down a slope can devastate anything in its path. Take the following steps to be ready.

BEFORE

Get a ground assessment of your property.

Your county geologist or county planning department may have specific information on areas

vulnerable to landsliding. Consult a professional geotechnical expert for opinions and advice on

landslide problems and on corrective measures you can take.

Minimize home hazards.

• Plant ground cover on slopes and build retaining walls.

• In mudflow areas, build channels or deflection walls to direct the flow around buildings.

• Remember: If you build walls to divert debris flow and the flow lands on a neighbor’s

property, you may be liable for damages.

Learn to recognize the landslide warning signs.

• Doors or windows stick or jam for the first time.

• New cracks appear in plaster, tile, brick, or foundations.

• Outside walls, walks, or stairs begin pulling away from the building.

• Slowly developing, widening cracks appear on the ground or on paved areas such as streets or

driveways.

• Underground utility lines break.

• Bulging ground appears at the base of a slope.

• Water breaks through the ground surface in new locations.

• Fences, retaining walls, utility poles, or trees tilt or move.

• You hear a faint rumbling sound that increases in volume as the landslide nears.The ground

slopes downward in one specific direction and may begin shifting in that direction under your

feet.

Make evacuation plans.

Plan at least two evacuation routes since roads may become blocked or closed.

Develop an emergency communication plan.

In case family members are separated from one another during a landslide or mudflow this is (a real

possibility during the day when adults are at work and children are at school), have a plan for getting

back together.

Ask an out-of-state relative or friend to serve as the “family contact”. After a disaster, it’s often easier

to call long distance. Make sure everyone knows the name, address, and phone number of the contact

person.
Insurance

Mudflow is covered by flood insurance policies from the National Flood Insurance Program. Flood

insurance can be purchased through a local insurance agency.

DURING

If inside a building:

• Stay inside.

• Take cover under a desk, table, or other piece of sturdy furniture.

If outdoors:

• Try and get out of the path of the landslide or mudflow.

• Run to the nearest high ground in a direction away from the path.

• If rocks and other debris are approaching, run for the nearest shelter such as a group of trees

or a building.

• If escape is not possible, curl into a tight ball and protect your head.

Sinkholes

A sinkhole occurs when groundwater dissolves a vulnerable land surface such as limestone, causing

the land surface to collapse from a lack of support. In June 1993, a 100-foot wide, 25-foot deep

sinkhole formed under a hotel parking lot in Atlanta, killing two people and engulfing numerous cars.

AFTER

Stay away from the slide area.

There may be danger of additional slides.

Check for injured and trapped persons near the slide area.

Give first aid if trained.

Remember to help your neighbors who may require special assistance—infants, elderly people, and

people with disabilities.

Listen to a battery-operated radio or television for the latest emergency information.

Remember that flooding may occur after a mudflow or a landslide.

Check for damaged utility lines.

Report any damage to the utility company.

Check the building foundation, chimney, and surrounding land for damage.

Replant damaged ground as soon as possible since erosion caused by loss of ground cover can lead to

flash flooding.

Seek the advice of geotechnical expert for evaluating landslide hazards or designing corrective

techniques to reduce landslide risk.
HOW TO RECOGNIZE PROBLEMS

Water generates & triggers most slope problems. Find where the water is coming

from. Get out in the rain & check areas like hillslopes, gullies, driveway & street

drainage, roof gutters & downspouts. Next, see where it flows & where it goes.

Concentrated flow can cause great damage.

STEEPER SLOPES HAVE

GREATER DRIVING FORCES

LOADING THE TOP OF A SLOPE

INCREASES DRIVING FORCE

LOADING THE TOE OF A SLOPE INCREASES

RESISTING FORCES

FILL AT THE TOP OF A SLOPE

INCREASES BOTH DRIVING

FORCE & STEEPNESS,

UNDERCUTTING AT THE

BOTTOM OF THE SLOPE

REDUCES RESISTING

FORCE WATER SATURATION OF SLOPES ADDS

DRIVING FORCE & REDUCES RESISTING

FORCE

SAFETY TIPS

 Conduct water to a safe storm

 drain discharge point.

 Keep gutters clean. Fix

 broken & leaking

 downspouts

homeowners

landslide

guide

for

landslide control

hillside flooding

debris flows

soil erosion

 WET, WEAK and STEEP -- Slope failure problems are caused by any

combination of water saturation and flow; weak, heavy earth materials; and, steep

slopes. Remember, WATER is the most common trigger of slope failure!

 STEEP SLOPES -- Problems occur on steep slopes, especially when slope of

one vertical to two horizontal is exceeded.

 DRAINAGE -- Channels, streams, gullying, ponding and erosion on slopes all

indicate potential slope problems. Road and driveway drains, gutters, down spouts

and other drainage can concentrate and accelerate flow. Ground saturation and

concentrated velocity flow are a major cause of slope problems and landslide

triggering.

 DEBRIS -- Deposition of soils and vegetation at the base of slopes show

erosion, flow and creep from ground cover above.

 VEGETATION -- Condition of vegetation indicate slope conditions. Bare slopes

may show erosion and sliding. Trees that bend downhill show creep of upper

soils. Trees tilting uphill may show deep rotational landsliding. Patches of younger

vegetation may show former slope failure. Horsetail ferns or other wet loving plants

often indicate saturated ground and springs.

 DEFORMED STRUCTURES -- Foundation cracks; doors and windows out

of line or sticking; tilted floors; sagging decks; cracks in masonry and chimneys;

cracks in driveways, curbs & roads, gaps between floors & walls, failing retaining

walls & tilted power poles can be warnings of slope instability.

 LOOSE FILL at the top of a slope due to yard waste, cut & fill land grading or

other process can aggravate slope instability.

Drainage concentrated

and discharged onto loose fill

on the down slope side of a

house by roof or driveway and

road drains is the most dominant

trigger of landsliding in areas of

residential development on steep, weak

slopes.

 E

A

B

 C

 D

What YOU can do to prevent landslide and slope stability problems:

 DIVERT, CONTAIN and safely DISCHARGE water around and away from

unstable slopes, yards and structures.

 Use SANDBAGS to divert water from uncontrolled spilling, such as over curbs

or from gutters and downspouts, or from washing into buildings.

 Use GROUND COVER to protect sensitive and unstable areas with plastic

sheeting or tarps, burlap or other material. Wood chips and straw may be worked

into the surface. Straw bales can retard velocity flow and erosion. Cover ground

cracks, such as from sliding or erosion, with plastic sheeting staked or loaded

down with weights. Protect cover from wind damage or other forces.

 CONTAIN FLOW by directing into road gutters, storm drains or non-eroding

stream beds. Flexible plastic pipe can be quickly installed. Redirect flow away

from slopes and properties. DO NOT concentrate flow onto slopes or your

neighbors property, or behind retaining walls.

 SAFELY DISCHARGE concentrated water to a safe,

non-erodible site such as a storm drain, street gutter

or rock bed of a stream. Coarse rock or

bales of straw can reduce the

impact of concentrated

velocity flow and can reduce

sediment transport.

Landslide Guide 3/5/97
MORE PERMANENT SOLUTIONS

Major problems require major hazard mitigation and repairs. The best and easiest

cure is to avoid the hazardous sites. Urban population pressures increase the

uses of marginal building sites requiring greater investment in stabilization

measures. Steep, weak hillslope areas require increased code and ordinance

controls to reduce risks to homeowners. Professional site investigations by both

a technical engineer and an engineering geologist have been shown to reduce

landslide damage over 95%. Technical solutions can greatly reduce the risks.

But, private insurance or government hazard programs DO NOT protect the

homeowner at this time.

Serious problems require serious help. Hillside flooding, debris flows, erosion,

and sliding often generate greater damage than the homeowner can manage

on his/her own. Serious problems require specialized professional expertise of

registered civil engineers with geotechnical speciality and registered engineering

geologists.

CONCRETE RETAINING WALLS

Concrete retaining walls can be constructed to withstand a large variety of

structural loading conditions. They are particularly useful in steep situations

where protection is needed close to the top or base of a slope. The strength of

the retaining wall is highly dependent upon the strength of the materials it is

made of and the manner in which they are put together. Because of the design

detail required for each situation a structural or geotechnical engineer should

be consulted when a concrete retaining wall is going to be used.

ROCK WALLS

Rock walls are essentially gravity walls made of stacked large rock. They

primarily provide erosion protection and limited earth support. Slope, rock

depth and wall height are critical to the stability of rock walls. Therefore,

they should generally be limited to 15 feet or less in height and

should be installed by professional rockery landscape

installers. Engineers should design higher walls.

WARNING!

If your house is in danger of landslide damage, protect people first and

EVACUATE IMMEDIATELY!

Danger Signs Include:

 Rapid water or slurry flow impacting house.

 In steep terrain; if flow stops or is irregular, evacuate fast!

 Debris-dam bursts occur very quickly.

 House cracks actively opening.

 House making noises.

 Walls or floors tilting.

 Ground cracks opening under house.

 Any portion of house falling away.

Serious problems require professional assistance. For help with major

hazards, consult a licensed building professional in your community and

your local building authority.

See Inset

Topsoil and vegetation

layer

Rock fill to permit

percolation of

water

Fabric barrier to

prevent mud

migration

Recommend min.

6 ABS perforated

drainage pipe

to conduct water away

from base of wall

Engineered Concrete

Retaining Wall

Topsoil and

vegetation layer

Well Draining Soil

(IE: sand)

BANK STABILIZATION

Banks that are steep and susceptible to landslides, or are already sloughing off

and encroaching upon a structure, are in need of a bank stabilization effort.

Many different levels of protection are possible and it is best to consult with a

geotechnical or structural engineer if you are in a hazardous area.

VEGETATION

On geotechnical or slope areas where there is no threat to life or

structures a vegetation planting plan may be the most reasonable

approach. The different types of root systems that plants

have can strengthen the cohesion of soils and bind the

soil structure together into a larger unit. This can add

resistance to potential landslide areas. Shallow

roots can stabilize the top layer of soil, while

deep tap or lateral root networks can

strengthen the lower base layers. Many

plants are particularly useful for bank

stabilization. Your local nursery will

be able to recommend plants

that grow well in your climate and

particular soils conditions.

Potential

failure planes

Backfill

Geotextile

Gravel

Water

Relatively

Impermeable Soil

Permeable Soil

Perforated drainage pipe placed on 3-6

inches of gravel. Pipe midpoint should be

located into the permeable soil layer

INTERCEPTOR DRAIN

Excavate trench into impermeable soil layer. Lay

geotextile into trench. Place gravel into trench and

extend gravel height to the maximum anticipated

water level. Overlap geotextile on top of gravel.

Backfill with excavated soil.

Landslide Guide 3/5/97