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close this bookRepairing Your Flooded Home (American Red Cross - FEMA - Federal Emergency Management Agency, 1992, 56 p.)
close this folder8 STEP : Rebuild and Floodproof
View the document(introduction...)
View the documentFloodproofing
View the documentFive Types of Floodproofing
View the documentBuilding permit
View the documentRebuilding tips
View the documentContractors


Don't just build it back; build it better. Now is the best possible time to think about floodproofing your home because you can take definite action to protect your property in the future. many floodproofing measures are quite simple, cost effective, and easy to put in place. By floodproofing as you rebuild, you can make the next flood easier on you and your wallet.


Floodproofing means to remodel or rebuild using materials and methods that will prevent or minimize damage from future floods. Consider the benefits to flood-proofing your home:

· By protecting your home from damage, floodproofing will save you money and aggravation during the next flood.

· Many floodproofing measures are inexpensive.

· Protecting your house from future flood damage will increase your property's resale value.

· Many floodproofing measures can be easily worked in during repair and rebuilding, reducing your costs.

· Some financial assistance programs can help pay for flood-proofing.

· By preparing for the next flood, you regain control over your future - a guaranteed way to reduce your level of anxiety and stress. You don't have to wait for the government to act; you can take care of protecting your home when you are ready.

· Floodproofing won't make it possible for you to stay at home in a flood. But it is likely to make it much quicker and easier for you to clean up the next time.

Before you repair or rebuild, the first thing you should do is talk to your town's or city's or county's building department. You will need to ask the following questions:

- What are the procedures for applying for a building permit? What inspections will need to be done?

- Is your home substantially damaged? (Substantially damaged means that the cost to restore your home to its "before damaged" condition would equal or exceed 50% of the market value your home had before the damage occurred.) The flood protection level is the level of flooding that you want your house to be able to withstand without damage to your house or your belongings.

Start by asking your building department what flood protection level it requires for your area. If there has been a flood higher than the level they give you, you should use that flood's level plus 1 or 2 feet for safety. The next flood may be worse.
Rebuild and Floodproof

The next step is to decide if you will be better off living in a different location, away from areas that flood. Ask your building official about government agencies that sometimes purchase property for open space or flood protection in areas that flood - you may qualify.

If you are sure that you will repair or rebuild your house in the flood-prone area, choose the floodproofing type that is best for your home or property. there are give basic types of floodproofing described here, as well as rebuilding tips to help you safely repair and rebuild.

Five Types of Floodproofing

1. Elevation

Most buildings can be raised so that the lowest floor is above the possible flood level. If you had foundation damage from the flood, you may need to raise the house to repair it. It will be easier and cheaper to elevate the house at that time.

There should be many contractors qualified to undertake elevating your house above flood level. Elevation or relocation are the only reasonable ways to protect your home if it is subject to coastal flooding or to deep flooding (more than six feet deep.) Elevation and relocation are also the most dependable measures for floodproofing your home.

An elevated building will need a new foundation. The contractor will jack up a structure and temporarily set it on a temporary framework called cribbing while the foundation is built underneath. The foundations of an elevated building may be columns, piers, pilings, or raised foundation walls. The elevated building will usually look better and have added protection if fill dirt is placed around the new foundation. But check with your building department before adding fill dirt. It may not be allowed in your community.

2. Relocation

Moving a building out of the flood-prone area is the surest way to protect it from flood damage. Most houses and smaller commercial buildings in good condition can be moved, and it is usually no problem to find contractors experienced in moving buildings. You will have to purchase a new lot unless your present lot is large and has a good spot on higher ground for your house. Relocation and elevation are the only reasonable choices for protecting a home that is subject to deep flooding (of more than six feet in depth) or to coastal flooding.

3. Floodwalls

Floodwalls, berms, and levees all work to keep floodwaters from reaching your house. They are built to at least the height of the flood protection level in your area. Floodwalls are usually made of concrete. Berms are simply small levees, usually built from fill dirt.

Floodwalls, berms, and levees can either surround the building (ring levee) or connect to high ground. They can also be built up against a building's foundation walls. a sump and pump will be needed to pump out water that seeps under the wall. Floodwalls, levees, or berms may not be allowed in your area if they could create a drainage problem on your neighbor's property. check with your building department before you build.

Floodwalls of all types work best in places where flooding is less than three feet deep. If flood-waters near your home develop swift currents, floodwalls, levees, and berms cannot be used - they may wash away. floodwalls and berms may not be appropriate for homes with basements.

If there is not enough room for a berm or levee, you may be able to build a floodwall made of concrete, which takes up less room. The walls should contain internal reinforcing bars to give added strength as well as to help walls resist cracking and settling over time. Walls must be properly anchored to withstand the same water pressure that can destroy basement walls.

4. Dry floodproofing

Dry floodproofing means sealing a building to keep floodwaters out. All areas below the flood protection level are made water-tight. Walls are coated with plastic or rubberized sheeting or special waterproofing compounds. Openings such as doors, windows, sewer lines, and vents are closed permanently, or can be temporarily sealed with removable shields or sandbags.

Dry floodproofing can only be done if the walls of your home are strong enough to hold back the floodwaters without collapsing. For this reason, dry floodproofing is not recommended if floodwaters are expected to be more than two or three feet above the ground level. Dry floodproofing is generally not appropriate for houses with basements or crawl spaces.

5. Wet floodproofing

Wet floodproofing means modifying a building so that floodwaters will cause only minimal damage to the building and contents. Building materials below the flood protection level are replaced with materials that are resistant to water. Floodwaters are allowed into the building to counteract the pressure of the water on the out-side of the walls.

You should furnish areas that have been wet floodproofed with light, portable furniture that can be easily and quickly moved before a flood. Objects that are difficult to move, such as furnaces, water heaters, appliances, and bookcases, are either put on platforms or reinstalled upstairs.

Wet floodproofing has one advantage over the other four floodproofing times: even the smallest efforts will significantly reduce flood damage the next time. Thousands of dollars can be saved simply by moving furniture and electrical appliances out of areas that will flood. If you decide not to use one of the other four floodproofing types, you should use wet floodproofing measures as you repair and rebuild. The rebuilding Tips in this section give more wet floodproofing ideas.

Building permit

One you've determined the repairs and floodproofing measures you are going to take, local codes generally require that you get a building permit. Before you make repairs or alterations to your home or property, make sure your plans are reviewed and okayed by your building department. You may also need to get the okay of our homeowner's association or mortgage holder before you make repairs or alterations to your home or property.

If you are just replacing items such as carpeting or wallboard, you will probably not need a permit - but you should check with your local building department before you proceed. You will usually have to get a permit for electrical work and repairs of structural damage, such as broken walls.

Most local and state building codes require that a building that is substantially damaged be treated as a new building. a new residential building must be built so that its lowest floor is at or above the flood protection level. In other words, if your home meets the criteria described above for "substantially damaged," you will have no choice but to elevate or relocate your home in order to meet local building codes.

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

Rebuilding tips

Give your house plenty of time to dry. Many problems result from rebuilding after a flood before everything dries. If it takes a week for the visible signs of moisture to disappear, allow at least another week for the parts you cannot see to dry. Don't try to force a swollen door to close. Don't force wooden parts to fit. When completely dry, the wood may regain its original shape.

There are small, inexpensive measures you can take to make your recovery easier after the next flood.

Products that resist water damage

· Concrete, concrete block, or glazed brick

· Clay, concrete, or ceramic tile

· Galvanized or stainless steel nails, hurricane clips, and connectors (in areas subject to salt water flooding)

· Indoor-outdoor carpeting with synthetic backing (do not fasten down)

· Vinyl, terrazzo, rubber, or vinyl floor covering with waterproof adhesives

· Metal doors and window frames

· Polyester-epoxy paint (do not use mildew-resistant paint indoors, especially on cribs, playpens, or toys because it contains an ingredient that is toxic.)

· Stone, slate, or cast stone (with waterproof mortar)

· Styrofoam insulation

· Water resistant glue


Move the main breaker or fuse box and the utility meters above the flood protection level for your home. Make sure each circuit is labeled so you know which circuits control which outlets and fixtures. If the electrical code allows, raise the electrical outlets and switches above your flood protection level.

If you are going 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 platform above the flood protection level. a water heater can be put anywhere near a hot water pipe. An updraft furnace located in a basement can be replaced with a downdraft furnace on a floor above the flood protection level.

Where the flood protection level is not too high, a furnace, water heater or other heavy appliance can also be raised on a platform inside the house. Put the appliance on concrete blocks or a wooden platform supported by concrete blocks. Make certain that appliances such as washers and dryers are secure and will not vibrate off the blocks or platform during use.

You can protect the furnace, water heater, washer, and dryer from shallow flooding with a low floodwall built around the appliance. a concrete or wooden wall 1 or 2 feet high can stop low-level flooding. The wall should be waterproofed with plastic sheeting or waterproofing compounds that can be purchased at hardware stores.


Wash and disinfect the studs and sills if the wallboard and insulation had to be removed. If you are going to rebuild the walls, remember that metal studs and sills are not damaged by water as much as wooden ones.

Pressure-treated wood will resist mildew and wood eating insects outdoors, but it may swell as much as untreated wood when soaked. Some kinds of pressure-treated wood should not be used inside the house, where they will come into contact with food or skin. (It depends on which chemicals were used to treat them.) Ask your lumber company to help you choose the right products for jobs you will do. They would also have consumer information sheets that give specific precautions for some products. Ask for them.


Think horizontal rather than vertical. Install the wallboard panels sideways so they are only four feet high. If the next flood is less than four feet deep, you only have to replace half the wall.

This drawing shows another suggestion. Leave the wall open one inch above the sill. The baseboard will hide this gap. When you remove the baseboard after the next flood, the wall cavity will drain freely and air will circulate better. Check your local codes, however. If a firewall is required, the building code may not allow the gap.

"Greenboard" or other moisture resistant wallboard is made for bathrooms and other damp areas, such as basements. It may be more sturdy when wet than regular wallboard. However, if soaked with floodwaters, it will present the same health hazard as regular wallboard and should be replaced.


Some floors are made with particle board or plywood, materials that fall apart when wet for long. Floor joists and some wood floors will regain their shapes if allowed to dry naturally.

After re-nailing, a wooden floor may need a little sanding to be smooth, or you can place a new underlayment for a new floor over it. Use screws or screw nails on floors and stairs to minimize warping. Do not lay new flooring or carpet until the subflooring is completely dry.


Do not paint until the surface is completely dry. If the surface still contains moisture, the paint will peel. Things look dry on the surface long before they are dry on the inside, and this can lead to costly mistakes. It may take several weeks for the surface to dry out enough.

To get an idea if a wall or floor is dry enough to paint, dry an area approximately 18 inches square with a blow dryer. (When checking a wall, select an area near the floor where it will be most damp.) Cover the area with a piece of clear plastic sheeting. Carefully seal all the edges with tape. Check the plastic 24 hours later. If there are beads of condensation on the side of the plastic that face the wall or the floor, it's still too damp to paint.

You can cover concrete surfaces with a clear coating or penetrating sealer to make cleanup easier next time. Don't paint over water stains - they will bleed through several coats of paint. Coat the stained area with shellac or a commercial stain killer before painting.

If you are going to dry flood-proof your walls, don't rely on waterproofing paints; they cannot keep floodwaters out. Such paints may protect a deck from rain, but they cannot protect walls and floors against the pressure of standing water. (Thick plastic or rubberized sheeting provides the most secure waterproofing seal.)

Products to Avoid

Avoid using or storing in areas likely to flood:

· Fiberglass or cellulose insulation
· Cork, corkboard
· Gasoline, weed killer, pesticide, lye, drain cleaner, swimming pool and other chemicals
· Linoleum
· Particle board, chipboard, fiberboard, paperboard, strawboard, Masonite paneling
· Wallboard, Sheetrock, drywall, gypsum
· Wallpaper


If you live near the coast, your home is likely to suffer damage from the high winds and floodwaters of a hurricane or nor'easter. Boarding up all your windows and doors are the best way to protect them from breaking and letting in the heavy rains that a coastal storm brings. Taping windows will not prevent them from breaking during a storm.

Cut plywood to fit each of your windows and doors well before a storm threatens. Label each piece so you'll know which window or door it covers. Store the plywood with the nails or other fasteners you will need to attach them. That way, you will be able to put the plywood up quickly when a storm threatens.


You may need a contractor to help you rebuild, especially to handle the difficult jobs such as foundation repair and electrical work. If you have been satisfied with work done by licensed local contractors, try them first. If they cannot help you, ask them for recommendations.

If you must hire a contractor you do not know, talk to several contractors before you sign anything. Reputable contractors would agree that you should take the following steps:

- Check on the firm's reputation. The local Better Business Bureau, home builders association, or building trades council are excellent sources. Ask if the firm has had unanswered complaints filed against it.

- Ask for proof of insurance. Be sure the contractor has disability and worker's compensation insurance. If the contractor is not insured, you may be liable for accidents on your property.

- Ask for references. Contractors should be willing to provide names of previous customers. Call some of the customers and ask if they would hire the contractor again.

- Ask for a written estimate. Check it to make sure it includes everything you expect the contractor to do. Some contractors charge a fee for an estimate, which is understandable because they have plenty of work to do after a flood.

- Ask for a contract. The contract should be complete and clearly state all the work, the costs, and the payment schedule. Never sign a blank contract or one with blank spaces. If a lot of money is involved, it may be worth your while to have an attorney look at the contract before you sign it.

- Ask for any guarantees in writing. If the contractor provides guarantees, they should be written into the contract, clearly stating what is guaranteed, who is responsible for the guarantee (the dealer, the contractor, or the manufacturer), and how long the guarantee is valid.

- Obtain a copy of the final signed contract. Once signed, it is binding on both you and the contractor.

- Don't sign off before the job is finished. Don't sign completion papers or make the final payment until the work is completed to your satisfaction. a reputable contractor will not threaten you or pressure you to sign if the job is not finished properly.

Areas recuperating from floods are often prime targets for less-than-honest business activities. Building codes often require that work be done only by licensed contractors. Some building departments and trade associations keep lists of contractors who work in the community.

Here are some points to remember:

· Be cautious when contractors you don't know offer "special deals" after a disaster or want to use your home as a "model home."

· Ask for complete financial details in writing and for an explanation of any differences from regular prices. Sales are worthwhile and they do exist, but be sure you are getting the services and products you are paying for.

· Do not sign a contract when a salesperson has pressured you. Federal law requires a three-day "cooling off " period for unsolicited door-to-door sales of more than $25. If you want to cancel such a contract within three business days of signing it, send your cancellation by registered mail. Other types of sales may have contracts with different cancellation clauses.

· 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 cost of the project.

· Make sure your contractor calls you or a qualified observer to inspect work before it is covered over. Shoddy work on sewers or basement walls will be hidden from view, and you won't know if there is a problem until the next flood. Most building departments will want to inspect electrical and plumbing lines before the walls are covered with wallboard or paneling.

If you are a victim of fraud or have problems with a less than reputable contractor, the state or local consumer protection office or public attorney should be able to tell you what to do.