After the Flood

Copyright © 1997 University Extension, University of Missouri. All rights reserved.

After the Flood

• Safety Rules and Recovery Procedures After a Natural Disaster
• Restoring Electrical Service After a Flood
• Disposing of Sewage and Garbage
• Priorities for Clean-Up and Repair
• Supplies and Equipment for Home Clean-Up
• Cleaners and Disinfectants
• Mildew-Removing Procedures
• Checking Damaged Buildings
• Cleaning & Repairing Flooded Basements
• Finding & Repairing Leaks in Roofs
• Getting Rid of Flood Odor
• Opening Flooded Windows
• Replacing Broken Window Panes
• Cleaning Flooded Floors &Amp; Woodwork
• Treating Warped &Amp; De-Laminated Floors
• Drying Walls
• Cleaning Interior Walls
• Repairing Exterior Siding
• Patching Plaster
• Installing Wallboard
• Installing Paneling
• Wallpapering

Safety Rules and Recovery Procedures After a Natural Disaster

1. See that your family is safe from flood crests, fire, or falling buildings.
2. Cooperate fully with local authorities, rescue squads, and local Red Cross chapters.
3. Help locate shelter, food, clothing, transportation, medical supplies, and medical help for victims.
4. Obey health regulations for personal and community protection against disease epidemics. Report any violations.
5. If premises have been flooded, flush plumbing fixtures with buckets of water to be sure they are open. Have health authorities inspect sanitory disposal systems. Water may have backed up into the septic tank, which in turn backs up into the plumbing system. This could be a health hazard.
6. Do not use water from private supply until health authorities have tested it. Boil drinking water 10 minutes or chlorinate by adding 1 teaspoon chlorine bleach per gallon of water.
7. Do not use food that has come in to contact with flood waters. Some foods can be salvaged if properly packaged. Consult local health officials if in doubt.
8. Sanitize dishes, cooking utensils, and food preparation areas before using them.
9. When entering damaged buildings, use flashlights only, not matches, torches, or any open flame. Watch for nails, splinters, holes in walls or floors, wet or falling plaster, undermined foundations, and gas leaks.
10. Do not use electrical system until it has been checked by an electrician.
11. Wait until any flood waters are below basement level before trying to drain or pump the basement.
12. Start clean-up as soon as possible. Thoroughly dry and clean house before trying to live in it. Delay permanent repairs until buildings are thoroughly dry.
13. Control rodents and insects.
14. Remove sediment from heaters, flues, and motors before using them. To speed drying, start stoves and furnaces as soon as they have been checked for safety.
15. Take all furniture and rugs outdoors to dry.
16. Dry and air bedding, clothing, and rugs as soon as possible to prevent mildew.
17. Set priorities. Accomplish most important tasks first, and avoid physical over-exertion.
18. Be sure children are safe and are being cared for at all times. Never leave young children alone or allow than to play in damaged buildings or areas that might be unsafe.
19. Give special attention to cleaning children's toys, cribs, playpens, and play equipment. Boil any items, for 10 minutes, that a toddler or baby might put in his mouth. Discard stuffed toys, plastic toys, waterlogged toys, and non-cleanable toys.
20. Keep chemicals used for disinfecting, and poisons used for insect and rodent control, out of the reach of children.
21. Wear protective clothing on legs, arms, feet, and hands while cleaning up debris. Wear rubber gloves while scrubbing flood-damaged interiors and furniture.

Restoring Electrical Service After a Flood

CAUTION: Wear rubber gloves and rubber soled boots for all work with electrical circuits, rubber is an insulator, and will help protect you from shocks.

DO NOT turn on lights or appliances until the whole electrical system has been checked by an electrician for short circuits. If such service is unavailable, and you need to do your own repairing, proceed as follows:

Turn Power Off

1. Disconnect the main electrical power switch, and any other switches controlling pumps or outbuildings. If your main switch is located in the basement, be sure all flood water has been pumped out before you attempt any work on the electrical system.

   Turn off the main switch for each building or at the yard pole. Be sure to stand on a dry board if possible. Avoid touching the metal handle of the switch box by using a piece of rubber, plastic, or dry wood.

   When touching any switches, stand on a dry board and use a dry stick or rubber gloves to pull handles.

2. Remove all branch circuit fuses, or place circuit breakers in "off" position to insure that power is off.
3. Disconnect all plug-in equipment, and turn off the switch at each piece of permanently connected equipment. Unscrew all light bulbs.

Clean and Dry the System

If water has gotten into conduits, connection boxes, etc., dampness or exposed wires can cause short circuits and fires. They must be dried before service can be restored. Shorten systems can also electrocute a person replacing fuses, especially if he stands on a wet surface.

1. Remove the covers from switches, convenience outlets, and other electrical connections.
2. Pull receptacles, switches, and wires about 2 inches out from their boxes. Do not disconnect the wires.
3. Clean out mud and dirt from the main entrance box. Allow wires and connectors to dry.
4. Use extreme caution in cleaning mud and dirt from the main entrance box. Since the power line enters here, this is the most hazardous part of the electrical system to work on. Assume the power line is hot even if a test light shows power is off. Never hose out a hot switchbox. Wear rubber gloves and rubber soled shoes. Do not touch anything wet, or stand in water while working on the box.
   

   If a sump pump is available and needed, remove all fuses except the main fuses and the one controlling the sump pump circuit. Then carefully turn on the main switch to see if the pump will operate.

   In an emergency, pull the electrical meter from its base to disconnect the power. Notify the electric company that you broke the seal.

5. Allow electrical wires and connectors to dry completely. This may take days depending on how wet the system is and if any heat is available.

Check the System for Electrical Shorts.

1. While standing on a dry board or ladder, and wearing rubber gloves and rubber soled shoes, check the main switch box to be sure all fuses are removed.
2. Close the main switch and look for sparks or smoking wires. These indicate shorted switch connections. If you see evidence of such shorts, carefully try to correct the problem. You may need a new switch.
3. If the switch is in working order, open the switch and insert a fuse in one branch circuit.
4. Close the switch to check for shorts in that branch circuit.
5. If the fuse doesn't blow immediately, wait at least 15 minutes to check for slower electrical leaks. Smoking wires and sparks in the circuit also indicate trouble, and you should carefully inspect all parts of the branch circuit you are checking. If there are any signs of smoking or heating, if the fuse blows, or circuit breaker trips, remove all fuses and open the main switch. You may need to do additional cleaning or drying, or you may possibly need to replace circuit parts.
6. Repeat steps 2 to 5 for each of the other circuits, one at a time.
7. After you have checked all the circuits and found them in good condition, once again remove all fuses and open the main switch. Replace wires for electrical receptacles, switches, and light outlets in junction boxes. Replace covers. Then check each branch circuit again, one at a time, by replacing one fuse at a time and closing the main switch.
8. If everything if OK, close the main switch.
9. For 24 hours, be careful when using receptacles and switches. There may be slow leaks that could cause shocks. Do not plug in electrical appliances that have been flooded until they have been reconditioned.
10. If some circuits are faulty, use only the undamaged circuits. Do not overload undamaged circuits with too many lights or appliances until normal capacity is restored.

    Some newer homes may have a ground fault circuit interruption system with their circuit breakers. This will probably need to be replaced.

Disposing of Sewage and Garbage

Damaged sewer systems are health hazards. It is important to get damaged septic tanks, cesspools, pits, and leaching systems into service as soon as possible.

If the area has been flooded, wait until the water level recedes before using the sewage system.

Trained personnel in local environmental regulatory agencies will help with these problems. They will be able to advise you about cleaning, repairing, and relocating installations if necessary. Problems with water purity, waste disposal, or pest control should also be referred to them.

Many states require approval before septic systems are altered or repaired.

Septic Tanks

Do not use the sewage system until water in the disposal or absorption field is lower than the water level around the house.

If the drain lines in the disposal field are dislocated, broken, or filled with silt, install new drain pipe in new trenches. Detailed information and instructions for installing a new system may be available from County Extension offices.

If you have to dig new trenches alongside the old title lines, it may be better to use polyvinylchloride pipe.

Do not use the sewer system until the flood has subsided and the ground water in the absorption area has returned to normal.

Temporary Sanitation

Until sewage absorption systems are back in normal working order, use any large container with a tight-fitting lid for a temporary toilet. Line the container with a plastic bag. After each use, add chlorine bleach or disinfectant to stop odor and kill germs.

A chemical camper's toilet will be quite useful in disaster situations.

Garbage

Try to remove garbage as soon as possible to prevent rat infestations and other health problems. Some garbage can be burned. Bury garbage that will not burn. Dig a hole 4 or 5 feet deep, and cover garbage with at least 2 feet of soil.

Priorities for Clean-Up and Repair

Priorities will vary with kind and seriousness of damage. Buildings may not be habitable during repair.

Before purchasing cleaners and disinfectants take inventory of what needs to be cleaned -- walls, floors, appliances, etc. Buy only cleaning products for type of work to be done.

1. Take photos of flood damage for insurance claims and tax deductions. Keep record of all expenses.
2. Assemble a "bare essentials" first aid kit for minor injuries that may occur while cleaning.
3. Examine building structure. Check foundations for settling, cracking, or undermining. Examine walls, floors, and windows to determine what repairs are necessary. You may want to repair only temporarily until extensive work can be done.
4. If basement is flooded, start pumping the water in stages. Pump about a third of the water each day.
5. Get electrical system in operation. If switch box is in a flooded basement, do not turn electricity back on until water has been pumped out. Take electrical appliances to a serviceman as soon as possible.
6. Get water system in operation. Disinfect wells and water system.
7. Shovel out mud and silt before it dries.
8. Before they dry, wash down flooded walls and floors with a hose. Start at bottom and work upward.
9. Scrub and disinfect walls and floors.
10. Start heating system, if possible, to speed up drying. Before operating it, heating system may need to be cleaned, dried, and reconditioned. Make sure chimneys are clean before starting system.
11. Dry out walls and floors. If necessary for proper drying, strip walls open up to water level. Drill holes in exterior siding. Complete drying may tales months.
12. Repair buckled walls and floors.
13. Make decisions about saving or discarding household contents. Clean and dry household items, furniture, carpets, clothing, dishes, bedding. Disinfect when necessary.
14. Treat items for mildew as needed.
15. Care for damaged trees, shrubs, and lawn.
16. Repaint, repair, refinish as necessary.

Supplies and Equipment for Home Clean-Up

Cleaning Supplies:

Equipment for Small Jobs:

Equipment for Large Jobs:

Cleaners And Disinfectants

Household cleaners help remove dirt. Disinfectants help stop the growth of disease-causing microorganisms carried in floodwater.

Powdered or liquid cleaners and disinfectants are more practical and much less expensive than aerosol products, since large areas will probably need to be cleaned.

Buy cleaners and disinfectants in the largest sizes available to reduce their cost. Farm supply, hardware, wallpaper, and paint stores often have these products in gallon or pound containers.

All products are not suited for all uses. Before using any cleaner or disinfectant, refer to its label for specific directions or precautions. Make sure the product will do the job you want it to do.

Many household cleaners and disinfectants are harsh on hands and may burn the eyes. Protect your hands with waterproof gloves. Avoid contact with eyes. If you splash or spill any product on your skin, wash it off immediately.

Cleaners And Disinfectants

*Where trade names are used, no discrimination is intended and no endorsement by the Cooperative Extension Service is implied.

Mildew-Removing Procedures

Checking Damaged Buildings

Safety precautions in entering damaged buildings

IF YOU SMELL GAS DO NOT ENTER.

1. Check for structural damage to make sure the building is not in danger of collapsing.
2. If you must enter at night, carry a battery-operated flashlight. DO NOT use a flame as a source of light. DO NOT smoke.
3. Turn off any outside gas lines at the tank or meter and let the building air for several minutes to remove gas fumes or odors.
4. Watch for electrical shorts or live wires before turning off the main power switch. Ask an electrician to check the system for short circuits before turning on any appliances or lights.
5. Watch for loose plaster and ceilings that could fall.
6. Open as many doors and windows as possible to remove moisture, odors, and flammable or toxic gasses. If windows are stuck tight, take off window strips and remove entire sash. Use a chisel carefully to avoid marring the woodwork. Force the sash up slightly, and remove it from the frame by pushing it from the outside into the hands of a helper. Be careful not to break the glass. If doors are stuck, drive out door hinge pins with a screwdriver and hammer, and remove doors.
7. Walks and fences damaged by flood waters are also a hazard until replaced or repaired.

Basements

Basements should be drained and cleaned as soon as the building is found to be safe. Pump or bail the water from the cellar when the water table is back to normal. Shovel out the mud while it is moist, to give basement floors and walls an opportunity to dry.

Drain the premises of all remaining pools of water. Remove, burn, or bury driftwood, rubbish, and decaying vegetation left in the yard.

Foundations

If you are not qualified to judge the stability of a foundation, hire a contractor to make this inspection. A neighborhood might join together in hiring a contractor for this work.

1. Examine foundations and supports for undermining. If walls or foundations have settled or cracked, uncover footings and raise, reinforce, or brace any settled sections. Be extremely careful when uncovering footings because of the possibility of cavernous wash outs.
2. If underlying material has been washed away, fill spaces to within 12 inches of the footing with gravel or crushed rock. Fill the remaining space with concrete reinforced with steel rods.
3. Check piers for settling or shifting.
4. If the building has shifted or the floors have settled badly, it might be necessary to install temporary bracing until extensive work can be done.
5. Drain any crawl spaces that contain water.
6. If the house or porches rest on open foundations, take care to see that there is no danger of the structure collapsing before you attempt to remove debris from underneath.

Walls And Ceilings

1. Wash out mud, dirt, and debris as soon as possible with a hose and mop, cloth, or sponge. Clean walls and floors before silt or mud dries.
2. Start cleaning the top or upper limit of flooding and work downward toward the first floor or basement.
3. Check walls with a level or plumb bob. If the building is out of plumb, or if the floors have settled or bulged, make sure that the foundation is sound and that the framing--sills, girders, and joists--is free from termite damage before renovating.
4. Walls that show evidence of settling or cracking may have been undermined. It may be necessary to dig down to the footings and reinforce or replace any sections that have settled. When needed, fill under footings with masonry or concrete, not with earth or gravel.
5. Brace walls where necessary.
6. Check mudsills, plates, soles, and anchorage. Replace or repair where necessary using redwood, cedar, or treated lumber.
7. To speed up drying of flooded studding and insulation, remove all siding strips or plaster from upper and lower parts of the walls. Do not repaint walls until they are completely dry. This might take several months. Flooded insulation may be ruined.
8. Look for loose plaster ready to fall from the ceiling, and break it down with a stick before you move around in the building. Wet plaster is heavy and dangerous if loose.
   
   Watch for more loose plaster as the house dries out. After the house is completely dry, repair damaged plaster on walls and ceilings. Badly damaged plaster walls can be resurfaced with gypsum board or plywood.

Floors

Flooded wooden floors will dry out slowly. Don't build fires to speed up their drying, as this could cause cracking or splitting from uneven drying. However, if the central heating system is operating, keep the temperature of the house at 60 to 70 degrees farenheit to hasten drying without causing additional problems.

1. To prevent further buckling and warping, drive nails where the floor tends to lift or bulge.
2. After floors are completely dry, plane or sand them level.
3. If floors are too badly damaged to be refinished, lay a new floor over the old or cover with carpet, vinyl, or linoleum.
4. If a concrete floor is badly damaged, break it up and install a new floor. If damage is minor, patch with a rich mixture of concrete containing no coarse gravel aggregate.

Roofs

1. Use plastic sheeting or roll roofing for temporary repair of solid deck roofs covered with asphalt shingles, wood shingles, or roll roofing.
2. Use knife consistency patching compounds to repair minor leaks.
3. You will probably have to replace damaged metal roofing on a spaced roof deck.

Don't rush to move back in. The house should be clean and dry before any attempt is made to live in it.

Cleaning & Repairing Flooded Basements

Entering

Before you enter a flooded basement:

1. Turn off the electricity, preferably at the meter.
2. Check outside cellar walls for possible cave-ins, evidence of structural damage, or other hazards.
3. Turn off gas or fuel service valves.
4. Open doors and windows, or use blowers to force fresh air into the basement.

Pumping

Do not use an electrical pump powered by your own electrical system. Use a gas-powered pump, or one connected to an outside line. Fire departments in some communities may help with such services.

More damage may be done by pumping water from the basement too soon or too quickly, than from letting the floodwater remain. Water in the basement helps brace the walls against the extra pressure of water-logged soil outside. If water is pumped out too soon, walls may be pushed up.

To help prevent such structural damage, pump the water from the basement in stages. Remove about a third of the water each day. Watch walls for signs of failing. If the outside water level rises again after the day's pumping, start with a new water line. The soil may be very slow to drain, but do not hurry the pumping. Whatever is submerged in the flooded basement will not be damaged further by delaying the pumping; serious structural damage may be prevented.

Cleaning

After water has been pumped from the basement, shovel out the mud and debris while it is still moist. Hose down walls to remove as much silt as possible before it dries. Floors and walls may need sanitizing, particularly if sewage has entered the basement. Scrub walls and floors with one of these sanitizing solutions:

1. Chloride of lime (25% available chlorine). Dissolve a 12 ounce can in 2 gallons of water.
2. High test hypochlorite (65% available chlorine). Stir 5 ounces into 2 gallons of water.

Oil stains in basements caused by overturned or damaged oil tanks may also be a problem following flooding. Commercial products (such as Neutroda) will help neutralize fuel oil. Products are available in powder form or an aerosol spray for hard to reach places. To remove oil stains and destroy odor, wipe up excess oil, shake or spray product on the spot according to manufacturer's directions, and let it set.

Repairing

Check supporting columns, beams, walls, and floors. Structural damage to flooded basements usually includes buckled walls, settled walls, or heaved floors.

1. Buckled walls are evidenced by horizontal cracking and walls moving out of plumb. When this condition is minor, you need not repair the wall immediately. However, any noticeably buckled wall will eventually collapse from normal ground pressures and seasonal temperature changes. When buckling has seriously weakened the wall, rebuild the damaged parts immediately. Build pilasters into walls over 15 feet long for reinforcement. Pilaster spacing should be 12 - 15 feet.
2. Settled walls and footings are indicated by vertical cracks either in small areas or throughout the structure. Repairs are difficult without special equipment. Contact a reliable contractor for this work.
3. Heaved floors are those that have not returned to their original level or have cracked badly. You may need to construct a new floor.
   
   1. Remove old, broken concrete.
   2. Place 6 inches of gravel fill on the basement floor surface.
   3. Cover area with a polyethylene vapor barrier.
   4. Lay a 4-inch concrete floor with mastic joints between the floor and walls. The floor should be reinforced with steel. Welded wire reinforcement placed at mid-height in the slab is a minimum reinforcement.

If a floor is badly cracked but has returned to its original level, and if there is sufficient headroom, place a new floor over the old one. Add a vapor barrier between the two floors. The new floor should be at least 2 inches thick.

In houses without basements, the area below the floor may be completely filled with mud. Remove the mud as soon as possible to avoid rotting joists or foundation wood.

Finding & Repairing Leaks in Roofs

Causes of Leaks

1. Defective flashing. Wet spots near a chimney or outside wall may mean the leak is caused by defective flashing, narrow flashing, or loose mortar joints. On sloping roof valleys and at junctions of dormers and roof, look for corroded, loose, or displaced flashing. Defective flashing often occurs around dormers and plumbing vent pipes.
2. Clogged downspouts or eaves. On flat roofs check for choked downspouts. Accumulated water or snow on the roof above the flashing may cause a leak. Ice accumulations on eaves sometimes form ridges that cause melting snow under the eaves to back up.
3. Cracks and deterioration. Roofing (especially wood or composition shingles) usually deteriorates first on southern exposures. Check southern slopes for cracking or deterioration.
4. Holes. Wet spots on plain roofs are usually caused by missing shingles or holes in the roofing. To find holes, look for light coming through places in unsealed attics. Stick a straw though the hole to mark the spot on the outside.

Repairing Leaks

Methods of repair will depend on the kind of roofing and the nature and extent of the leak.

1. Missing shingles. Replace missing shingles with similar shingles or pieces of rust- resistant metal. (In an emergency you can use metal cut from a tin can.)
   
   1. Paint the metal on both sides and slip it under the upper layer of shingles. Be careful not to dislodge or loosen sound shingles.
   2. Cut out old nails with a long, thin, cold chisel.
   3. Cover exposed nails with roofer's cement.
2. Holes
   
   1. Patch small holes with metal screws. Use neoprene washers in low places.
   2. Repair large holes by replacing metal sheets or patching with a heavy cloth or canvas and elastic roofer's cement. Apply cement carefully over the patch to prevent canvas from sagging into the hole.
3. Cracks
   
   1. Brush on two coats of roof coating.
   2. Place heavy cloth or light canvas over the cracked area, extending the cloth approximately 6 inches beyond the cracked area.
   3. Use a roofing brush to smooth out cloth, and brush on two thin coats of roof coating.
      
      Keep cloth smooth while brushing.
      CAUTION: Do NOT walk on patched section.

Getting Rid of Flood Odor

To get rid of the stench that often accompanies flooding, scrub all interior surfaces that were in contact with flood waters. Use hot, sudsy water followed by a rinse solution of 2 tablespoons sodium hypochlorite laundry bleach (such as Clorox) to a gallon of water. Or use a household disinfectant such as Lysol, following manufacturer's directions. Repeat the scrubbing and rinsing if necessary until odor is gone.

Opening Flooded Windows

Get windows open as soon as possible to speed up Raising windows in a building that has been flooded may be difficult, since window frames and sashes will probably be watersoaked and swollen. Don't try to pry windows open. Panes or sashes will probably break if you try to force them. To open windows:

1. Remove side molding strips in front of inside sash. Molding strips or stops are usually nailed or screwed on, and can be easily removed.
2. Go outside the building and remove the sash by pushing one side gently toward the inside. Lift the sash inside.
3. Allow the sash to dry thoroughly before trying to fit it back into the window frame.

Replacing Broken Window Panes

Prepare Sash

1. If you need to remove the sash from the frame to make repairs, use a broad chisel or other prying tool to remove vertical strips holding sash in frame. Remove sash and place on a horizontal work surface.
2. If you plan to leave sash in place during repairs, chisel out old putty to free loose or broken panes. Wear gloves, and be careful to avoid being cut.
3. With a pair of needle-nose pliers or a screwdriver, remove glazier's points (used in wooden sashes) or metal clips (used in metal sashes).
4. Scrape away putty sealing glass to groove on outside of pane.

Cut Glass

You can buy glass to fit, or cut your own from larger pieces you have available. Wear gloves and work on a solid surface covered with newspapers.

1. Measure glass, using a ruler or straightedge. Allow 1/16-inch space on each side.
2. Holding glass cutter between your first and second fingers with your thumb under the handle, make a smooth continuous stroke along the straightedge toward yourself.
3. To complete the break, hold small pieces firmly and bend quickly away from the cut. Tap larger pieces with cutter handle on opposite side over the scored line. For safety, wear gloves during this step.

Install Glass

1. Check pane size again. Make sure there is at least 1/16-inch clearance on all sides to assure a tight putty joint.
2. Remove panel. Apply glazing compound or putty all along the groove holding the pane. (Use the kind of glazing compound recommended for your type of frame material.) Roll compound into 1/4-inch rope-like lengths. Place it in position.
3. Set pane in place. Press down gently on all sides of the pane to depress glazing compound into a flat film and to seal the exterior joint.
4. Insert glazier's points (one centered on each end and two along each side in a wooden frame) or metal clips (in a metal frame) to secure the pane.
5. Apply glazing compound on interior side. First apply a generous amount of compound by drawing a loaded putty knife across the mullions (pane separators) on edges of sash at a right angle. Then draw the knife parallel to the frame to smooth the compound into a triangular bead. Size the bead so that glazing compound is not visible from the other side of the frame.
6. With the putty knife remove excess putty from the outside of the frame. Smooth remaining putty edge.

Clean Pane

1. Remove specks of glazing compound with turpentine or benzene.
2. Paint when compound is dry.

Cleaning Flooded Floors & Woodwork

Cleaning

1. Shovel out the worst of the mud and silt before it dries. Use a hose if necessary.
2. Before the house has dried out, scrub floors and woodwork with a stiff brush, plenty of water, a detergent, and a disinfectant. Remove mud and silt from corners, cracks, and crevices.
3. Give floors a final thorough washing with a non-sudsing cleaning product.
4. Sections of subfloors that separate must be replaced to avoid buckling. When floor coverings are removed, allow subfloors to dry thoroughly, even though it may take several months.
5. For wooden floors, remove a board every few feet to reduce buckling caused by swelling. Ask a carpenter for tips on removing tongue-and-groove boards.
6. Clean and dry floor thoroughly before attempting repairs.

Remove Surface Mildew

1. Heat the room to a temperature of 50° to 60° F to help dry mildewed wood.
2. Scrub mildewed floors and woodwork with a mild alkaline solution such as washing soda or tri-sodium phosphate (4 to 6 tablespoons to a gallon of water), available in paint and grocery stores. Or, use a cloth dipped in hot water and a small amount of kerosene or in a mixture of borax dissolved in hot water.
3. Rinse with clean water.
4. Allow wood to dry thoroughly.
5. Apply a mildew-resistant paint.
6. Replace badly infected wood--preferably with treated or decay-resistant wood.

Bleaching Wood Stained by Mildew

1. Remove paint or varnish with paint remover.
2. Apply a solution of 3 tablespoons oxalic acid dissolved in a pint of water to the stains. (Oxalic acid crystals can be purchased at drug stores. Oxalic acid is poisonous. Label it clearly and keep out of children's reach.)
3. Rinse with clean water.
4. Dry thoroughly before refinishing.

Refinishing

You may prefer to have floors professionally refinished. If you decide to do the work yourself:

1. Be sure floors are thoroughly dry.
2. Sand the surface until it is clean and smooth. (Heavily planed floors may never look good again, but they can serve as a base for carpeting, tile, or sheet flooring.)
3. If floor is oak, apply a filler, then apply two coats of a penetrating floor seal or spar varnish. Sand between coats.
4. Apply vanish, following directions on can.
5. Treat fir flooring in the same way, but omit the filler.

Vinyl Floors

Vinyl floors with wood subflooring can be replaced. With concrete floors, removal isn't necessary except to hasten drying of the slab.

Loose tiles may be replaced individually if the floor hasn't been soaked. If water has seeped under sheet flooring, remove the entire sheet.

While cleaning, wash exposed skin frequently in purified water. Wear rubber gloves for extra protection against contamination.

Open windows and doors and use fans to provide adequate ventilation.

Treating Warped & De-Laminated Floors

Some warped wood flooring is repairable and some is not. The extent of damage will depend partly on the kind of material used in the floor. Different woods react differently to dampness or flooding.

Plywood

Many homes have plywood subfloors. Plywood usually separates (de-laminates) from excessive moisture. This will make the covering material (carpet, sheet-flooring, or tile) buckle.

If only a small section of the subfloor has separated, replace that section with new plywood. If the entire floor has de-laminated, either remove the entire subfloor and replace it, or renail new plywood over the old. Consult a reliable contractor for this work.

Hardwood

Badly warped hardwood floors usually can't be repaired. If the floor is obviously beyond repair, take it up and discard it. Allow subflooring to dry for several months before installing another floor over it.

1. Clean and dry the floor completely before attempting any repairs. This may take weeks or even months.
2. If the floor is still warped in places when it is dry, remove strips adjacent to the bulges, and plane them on their edges. This will give space for the warped boards to flatten out in time. (If boards are tongue and groove, consult a carpenter about the special techniques necessary for this work.)
3. You may be able to draw some buckled flooring into place by nailing the bulged spots. Some humps may be removed by planing or sanding. Heavily planed or sanded floors, though unsuitable to be used uncovered, can serve as a base for new flooring, or for carpet or resilient floor covering.

Pine

Warped wide pine board flooring will often flatten out after it has thoroughly dried. Clean the floor and let it dry for several months. Using the furnace as much as possible during the drying time will speed up the process. (Do not build fires to hasten drying.) Do not try to repair the floor until it is dry. If any boards are still slightly warped when dry, use the same technique as for warped hardwood floors (see 1 to 3 above.)

When laying a new floor or subfloor, remove baseboards and moldings. The finished floor should be the same level as the original floor, if possible. If floor level changes, doors must be refitted to the new level. Consult a carpenter before attempting this work.

Drying Walls

Inner Walls

One the first things you should do when re-entering the house after a flood is to open windows to allow air circulation. If fans have been serviced and electricity has been restored, use them to move air through the house and improve drying conditions.

If a home has been flooded, even for a short time, the walls may be damaged. Many wall coverings will appear to have withstood the flood well, at least initially. Surfaces such as sheetrock and paneling that have not been flooded for long periods could weather the flood well. However, where the water remains for several days, sheetrock could carry it, through capillary action, up through the wall, in many instances to the ceiling, far above the level of flooding.

In the case of paneled walls that have been flooded for several days, the layers of paneling may separate. If the panel is made of pressed board, the entire panel may come apart as the water softens the glue. However, on most homes that have not been flooded for a long time, the primary concern will be removal of the wet insulating material from the walls and the drying that needs to take place once it is removed.

Walls must dry from the inside out. The interior framing of walls should be allowed to dry thoroughly. Sometimes this process takes weeks or even months. To release water and mud from walls, remove top and bottom strips of siding on the outside of the building. Drill several holes in walls near the inside floor line.

The total drying time will depend partially on the amount of dry air that can circulate through the studding (called "chimney action"). To provide for maximum chimney action, first consider the construction of the building.

Fire Stops or Cross Bracing

These are horizontal or diagonal braces between the vertical supports or studs.

Cross bracing will prevent chimney action between the studding. However, cross bracing is not usually found in modern construction, except in two-story houses where it has been specified. To allow free air movement, remove interior or exterior wall covering wherever cross braces are located. To check for cross bracing or fire steps, extend stiff wire into the wall cavity.

Insulation

Most types of insulation will be ruined if water soaked. You will probably have to replace flood-soaked insulation.

1. Loose fill (such as vermiculite) will settle to the bottom of walls. As it dries it can be removed. If not removed, loose fill insulation will create odors and eventually cause decay of the studding.
2. Rock wool batting insulation will also bunch and settle. If it is absorbent it will create odors and could eventually cause studding decay.
3. Fiberglass insulation holds water for a very long time. Walls that outwardly appear dry have been opened 6 months after a flood, and the insulation has contained the same level of water it held when first flooded. This water provides an ideal environment for decay-causing bacteria to develop in the wall. It only take several months or years, but the walls and framing material will decay and severe structural damage may occur.
   Homes that have wet fiberglass insulation have severe problems with mildew and musty odors as a result of the continuing source of moisture.
4. Reflective surfaces (such as alumninum foil) will probably lose their reflective ability, thus decreasing their insulating effectiveness. This material itself should be undamaged.

Wall Coverings And Finishes

Vinyl-covered wallpaper prevents the wall surface from drying because of its impermeable surface. Bacteria may feed on the wet wallpaper paste and cause discoloration and deterioration between the wallpaper and the sheetrock.

Plaster will take weeks or even months to dry, but may not be ruined by water. Old plaster, however, may disintegrate after being wet for a long time.

Dry wall (plaster board) will warp and disintegrate in water. Warping above the water level can also be expected. Drywall that has been submerged must be replaced.

Laminated paneling (plywood, masonite) will separate and warp above and below the water level. The extent of damage will depend on how long the paneling was submerged and how quickly moisture is removed from the studding. Slow drying decreases the possibility of elimination.

Several of these effects may not be visible right after the flood, but steps need to be taken immediately to avoid severe problems later.

1. Open the wall to at least the level of the flooding. A circular saw can be used on sheetrock walls to cut in a straight line around the wall at the level of flooding. Be careful not to cut into electrical wiring.
2. If the walls are paneled, remove the baseboard and pry the paneling loose. Prop the paneling away from the wall, remove the insulation, and let the paneling dry in that position. This could eliminate the need for buying new paneling material.
3. Remove the wet insulation from all walls. Then wash the walls thoroughly, using disinfectant. A 3-gallon garden sprayer works well. One cup of household laundry chlorine bleach to a gallon of water can be used as a disinfectant.
4. Spray the wall cavities thoroughly and allow the walls to stay open for a month to 6 weeks to allow thorough drying before re-insulating and covering.
5. Borrow a moisture meter from your County University Extension office to determine if wall cavities are dry enough to begin remodeling.
   
   At this point, you may want to consider a type of insulation and wall covering that will withstand flood waters without the need to open wall cavities afterward if there is a possibility of future flooding.
   
   Another possibility is to replace flood damaged walls with a wainscoting, assuming the level of flooding is no higher than 3 or 4 feet above the floor.

Siding

1. Masonry will dry slowly but will be undamaged except for possible cracking or settling. Open inside walls to prevent mildew and decay of wooden supports.
2. Lapped siding (wood, asbestos, aluminum). Remove strips or sections to dry insulation and studding. The type of sheathing will determine drying rate. To prevent oxidation, make sure backing of aluminum siding is dry.

Sheathing (material between studding and finish siding)

1. Wooden boards will dry slowly and some will warp. If possible, renail warped areas before they dry. Replace those that are too badly warped to salvage.
2. Sheathing board is usually absorbent and will be difficult to dry. Some will disintegrate or separate and must be replaced.
3. Plywood will probably separate in places and must be replaced. Marine plywood will not warp or separate, but is generally considered too expensive to use in residential construction unless the building is subjected to frequent flooding.

Qualified workers to make these repairs may be hard to find because of the large amount of work needed to be done immediately. Use caution in selecting workmen, and only use those who are experienced and reputable.

Cleaning Interior Walls

1. If walls have been flooded, hose them down, if possible, while they are still damp to remove most of the mud and silt.
2. Scrub with a sponge and warm detergent solution or a commercial cleaner. Clean a small section of the wall at a time.
3. To get rid of the stench that often accompanies flooding, rinse with a solution of 2 tablespoons sodium hypochlorite laundry bleach (such as Purex or Clorox) to a gallon of water. Repeat the scrubbing and rinsing several times if necessary. Household disinfectants such as Lysol can also be used. Follow directions on container.
4. Work from the floor to the ceiling to prevent streaking. Rinse with an old bath towel wrung out in clear water. Overlap sections.
5. Clean the ceiling last.
6. Allow walls to dry thoroughly before repainting, repairing plaster, papering, or applying any wall covering. Four to 6 weeks should be allowed as a minimum drying time. Total drying time will depend on weather conditions. You may need to remove baseboards or sections of the walls to dry interior studding and insulation (see Drying Walls).
7. If mildew appears on walls, scrub with a solution of trisodium phosphate, a disinfectant, or a solution of 1/2-cup bleach and 1/2-cup mild detergent in a gallon of warm water.

Repairing Exterior Siding

1. Strip drywall and insulation from inside wall. Replace with new material with moisture barrier on the inside. (Insulation can cause skin irritation. Wear protective skin covering when working with it.) Clean electrical outlets, and check wiring.
2. Check for silt deposits in crevasses back of siding. If crevasses are filled with silt, remove siding, and clean out all silt. Silt left in crevasses will trap moisture, causing mold and peeling paint.
3. Check for cracked or warped siding. If only a few boards are warped or cracked, replace them individually. If all siding is warped, cover entire wall with new material. You can install new siding over old, if there are no silt deposits behind old siding. This will also help improve insulation.
4. Cover or replace warped siding. It is easiest to cover warped horizontal beveled siding with new vertical siding, and to cover warped vertical siding with horizontal siding. Installing new siding over old will require trim work around doors and windows. Consult a carpenter for installation details. Siding is available in vinyl, aluminum, and wood. Wood siding may be either natural or pre-finished. Vinyl and aluminum siding are permanently colored.

Patching Plaster

Do not attempt repair plaster until walls and inner walls (studding and insulation) are completely dry. If walls were flooded extensively, you may need to wait 4 to 6 weeks, or perhaps several months, before attempting repairs. Use a moisture meter to determine dryness. One can be borrowed from your County University Extension Office.

Use ready-mixed spackling compound, dry powder spackling compound, or patching plaster, as recommended for your repairs.

Prepare the Hole

Fine cracks and small holes may need little or no preparation before they are filled.

1. Brush or chip away loose dirt or broken pieces of plaster from large holes.
2. Undercut large holes by making cracks wider at the bottom than at the top surface.
3. Scrape out loose plaster and plaster crumbs.

Mix Plaster

Mix enough spackling compound to do the whole room at one time. Mix patching plaster in small amounts, since it dries in less than 30 minutes.

Pre-mixed spackling compound requires no additional preparation. Mix dry powder in a small pan. Stir to a smooth, lump-free consistency that is stiff enough to hold its shape, but spreads easily.

Fill Holes

1. Nail hole or small hole. Pack the plaster in, and smooth it off at the same time by criss-crossing strokes. Press hard enough to wipe all extra plaster off the wall with the last stroke.
2. Larger holes or deep cracks more than 1/8 inch across. Use patching plaster.
   
   1. Mix plaster. Follow directions on package.
   2. Wet edges of crack or hole thoroughly before filling.
   3. Fill hole or crack half full.
   4. Let dry.
   5. Wet it down again, and apply a second coat so that patch is even with old plaster.
   6. Let dry.
   7. Sand lightly. Fill any small depressions with spackling compound.
3. Medium-sized holes through the wall.
   1. Wad up several sheets of newspaper and push them through the hole. Keep stuffing until paper catches on the back side of the partition. Or, use pieces of rustproof copper or plastic screen. Fold mesh into bowl shape. Push it into hole so the open end catches against back side of the wall. Flatten the front of the mesh where you will plaster.
   2. After filling hole with paper or wire, wet down with water.
   3. Pack patching plaster around the edges with a putty knife to gradually fill the hole.
   4. Let plaster dry after each application.
   5. After final application, let plaster dry overnight. Plaster will shink slightly as it dries.
   6. With a trowel or putty knife, apply extra layers of plaster until hole is level with surrounding wall.
   7. Smooth a thin layer of spackling compound on patch.
4. Large holes. These may need a piece of plaster board as base.
   1. Chip out irregular pieces to make hole rectangular.
   2. Cut plasterboard to fit, and nail to wood laths or exposed studs.
   3. Wet surface and edges of old plaster.
   4. Smear patching plaster around the edges and over the top.
   5. Pack plaster firmly where the board meets the old plaster.
   6. Just before plaster is completely hard, wet it lightly with water, and drag a wet trowel finely over the surface to smooth it.

Installing Wallboard

Gypsum board or plasterboard may be applied directly to framing. It is available in 4-foot wide panels, 3/8, 1/2, and 5/8 inch thickness, and varying lengths. Eight and 12 foot lengths are standard. Features such as special soundproofing and water resistance are also available. Check with your building supplier if such special features are desired.

To Apply Wallboard:

1. Be sure framing is sound and dry, and remove any decaying material.
2. Treat areas adjacent to decayed wood with wood preservative.
3. Replace decayed wood with new wood, properly treated with wood preservative if it is in contact with the ground.
4. Check that walls are plumb.

Install vapor barrier
Many forms of insulation and some wallboards have an integral vapor barrier, but this may not protect the total wall cavity. Use a 4 mil polyethelene plastic film. The film should fit snugly around doors, windows, and other obstructions. Seal any joints or openings with tape. Avoid puncturing the film. Fasten film to studs with staples or small nails, using only enough fasteners to hold it in place until finish wall material is installed.

1. Use 3/8-inch thick panels for joists or furring strips 16 inches apart, and 1/2-inch wallboard for joists or strip spacings up to 24 inches. Some building codes require specific thickness in some parts of the house. Check with your contractor about this.
2. Stagger panels so that end joints do not align.
3. Nail panels every 6-8 inches with annular ring nails recommended by wallboard manufacturer. Use a hammer with a slightly rounded face to depress or "dimple" the surface of the panel. Do not break face papers. Keep nails 3/8 inch in from all ends and edges of panels. Use two T-shaped braces to support the panels prior to nailing.

1. Use 3/8-inch thick panels for all stud spacings 16 inches apart. Use 1/2-or 5/8-inch thick panels for stud spacings up to 24 inches. Some building codes require specific thicknesses in some parts of the house.
2. Hold panel firmly against framing.
3. Nail all joints over framing every 6-8 inches, as for ceiling panels. Nail center of panel first, and proceed toward ends and edges.

Finish joints with tape and compound. The long edges of most panels will be tapered. Use mesh or perforated tape and pre-mixed compounds for ease in obtaining a smooth continuous surface. You may also use a topping compound for an additional overall surface. Finish wallboard may be wallpapered or painted.

Installing Paneling

Paneling is available in different price ranges and sizes. Most paneling is made of laminated plywood or reconstituted material such as hardboard, particleboard, flake board, or chip core. Standard sizes are 4' x 8' or 4' x 7', but 10' lengths are usually available on special order. Sheets can be either 1/8", 3/16", or 1/4" thick. Matching trims and moldings are also available.

Selecting Paneling

When selecting paneling, consider the location of walls. Special features may be desirable in certain locations:

1. Basements. Most basements will have some dampness. Select 1/4" paneling and waterproof the walls before installing it. A plastic sheet vapor barrier is recommended.
2. Above-ground supporting walls. Paneling of any thickness is suitable for installation above ground. For outside supporting walls, use a vapor barrier to protect against moisture migration and possible warping, even if panels are treated.
3. High moisture areas. Some paneling is made for high moisture areas such as showers, baths, and kitchens. Select paneling specifically manufactured for use in these areas.
4. High heat areas. When selecting paneling for a kitchen, furnace room, fireplace room, or other area near a flame or high heat source, make sure the panel material has a flame spread rating of no more than 50.

Installing Paneling

1. Walls in good condition. If walls are free from loose plaster, paint, and paper, paneling may be applied directly to wall surface without furring strips. Each panel should be carefully fitted and butted to existing trim and woodwork. Paneling may be 1/8" thick. Apply panels to wall with panel adhesive, allowing 1/32" to 1/16" clearance between edges of adjacent panels.
2. Walls in poor condition. Strip walls down to wall studs. Tear out old woodwork if it is in bad condition. You may need to use 3/8" furring strips to compensate for thickness of the old wall, especially if you keep the old woodwork. Use 1/4" paneling over studs and furring strips. Adjust electrical switches and outlets, if furring strips are used.

Acclimate Panels

Forty-eight hours before installation, place panels in the room where they will be installed. For good air circulation, separate them with 1" x 2" 's or stand them free. This will allow moisture-sensitive panels to be more accurately measured and installed.

Measure, Fit, and Cut

Use a 2' framing square and carpenter's tape for accurate measurement and marking. If you are using a portable electric or radial arm saw, cut panels face down. With a hand saw, cut panels face up.

Nail in Place

Use nails recommended by panel manufacturer. Nail over furring strips, starting in center of panel and working toward edges.

Wallpapering

Tools needed

Prepare the Walls

1. Remove any old wallcovering. If you can't get the old covering off without damaging the wall, seal it with a coat of shellac.
2. Scrape or sand rough paint or plaster.
3. Fill cracks and holes with spackling compound. Sand smooth.
4. Wash painted walls with tri-sodium phosphate and rinse with clean water. Remove paints or stains that "bleed" or colors will come through the wallpaper. Or, seal old finish with shellac.
5. For best results, unpainted plaster, wood, or plasterboard walls should be sized with a recommended primer. Wall sizing is available in paint stores. Follow directions on can.
6. Remove electric outlet covers and switch plates.
7. Paint any trim or woodwork before handing paper.

Measure Wall with Plumb Line

1. Choose the least conspicuous corner in your room, preferably close to a closet, window, or door.
2. Measure from that corner to a point about 1 inch narrower than the wallcovering. For example, if the wall covering measures 27 inches, measure out 26 inches.
3. Drop a plumb line (a piece of string with a small weight such as scissors or a pocket knife at the end of it) at that spot, and mark along the line. This line will be your starting point to ensure that wallcovering is hung straight.

Hang Wallcovering

1. Measure wall from ceiling to baseboard in several places to determine the maximum height. (In a normal room, the wall may be higher in some places than others.)
2. Add 3 or 4 inches to the maximum height, and cut a strip of wallpaper that long. For example, if the maximum height is 96 inches, cut a strip 100 inches long. This will allow for slight shrinkage and uneven ceiling or baseboard.
3. Cut only one strip at a time. Be sure to match patterns.
4. Working on a large table or the floor, cover the back of wall covering with paste. Use extra paste along edges. If using pre-pasted wallcovering, dip the cut paper in a container of lukewarm water instead of applying paste after cutting.
5. Fold the strip with wet sides together top to bottom.
6. Line the strip with the plumb line on the wall, and overlap it at ceiling and baseboard. Use a smoothing brush or squeegee to press wallpaper to wall. Try to avoid creasing it. Move any air pockets to the edges and out.
7. Match second strip along edge of first. Butt edges, but do not overlap. Avoid stretching wallcovering.
8. Roll seams lightly with a seam roller, unless you're hanging embossed or flocked wallcovering. With these, tap seams down with the tip of the smoothing brush bristles.
9. After hanging three strips, trim them at ceiling and baseboard with a razor blade or knife.
10. Proceed around the room following this method. Don't skip areas around doorways and windows. As you finish each strip, wash it with clean water and a sponge to remove excess paste.

Corners

Wall corners are seldom straight. Cut the strip to cover the corner so it extends 1 inch onto the next wall. The succeeding strip should bs hung with the first edge flush against the corner, overlapping the first strip by 1 inch.

Match patterns at corners. You may need to use special adhesive when overlapping vinyl over vinyl. Check with your dealer. When hanging plain colors or random matched textures, reverse every other strip top to bottom. The color will come out more uniform.

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