As soon as floodwaters recede, make sure the power is off and check for structural damage and infestations (snakes, fire ants, etc.), then get started as soon as possible to clean and dry everything quickly and thoroughly to prevent mold and rot. All wet materials, including wood, should be allowed to dry thoroughly before being covered or enclosed, so as not to impede full drying. Also, some materials may not recover and need replacement.
A professional water damage restoration contractor with special drying equipment is the best and safest way to go. Yet, after a flood, many homeowners don’t have that option.
For safety, wear protective clothing on legs, arms, feet and hands while cleaning up debris. Wear rubber gloves and goggles while handling flood-damaged items. Also wear a NIOS respirator, rated N-95 or higher since mold and other air contaminants are likely.
Since flood water can be contaminated with sewage and other biohazards, cleanable surfaces should be disinfected as well as cleaned. Disinfectants should be chosen and used carefully because they can pose a hazard, too. A variety of disinfectants and sanitizers are commercially available. Read labels carefully to determine appropriate uses, safety measures and dilution instructions.
Bleach solutions (such as ¼ cup concentrated liquid chlorine laundry bleach to a gallon of water) are commonly used because they are economical general purpose disinfectants. However, chlorine bleach can damage finishes, colors and metals, and pose hazards to people. Never use chlorine bleach in or near the air conditioning system. Never mix bleach with products containing ammonia or acids; that can produce toxic fumes.
In general, porous materials that have absorbed contaminated floodwater should be removed and properly discarded, except for solid wood and sometimes plywood. Solid materials, such as plastics, metals, glass solid wood, masonry, etc. can be cleaned. It's most effective to clean first, then disinfect in a separate step. Non-phosphate cleaners are recommended to avoid leaving behind a phosphate residue that could provide food for mold growth.
Do not sand or scrape painted surfaces in a home built before 1978 unless it has been inspected and found free of lead-based paint. Even tiny amounts of lead are a hazard to anyone, and can permanently harm a child's brain development. If you hire help, be sure the contractor is certified by EPA as a Lead Certified Renovator. Visit www.epa.gov/lead for more information.
Begin by removing wet carpets, carpet pads and rugs within 48 hours, if possible. That's how long it takes for mold growth to begin. Disinfect the slab or subfloor. You may be able to have valuable rugs cleaned, disinfected and dried, but flooded carpet pads should always be replaced.
Remove vinyl, laminate and other impermeable flooring over wood subfloors immediately after the flood has receded. Clean the subfloor. Drying could take weeks in a humid climate, but much less time if you can dehumidify the space. A buckled subfloor may flatten out on drying; be patient.
For wood floors, carefully remove a board every few feet to reduce buckling. Leave open until the flooring is dry. Solid wood, if not split, can settle back as it dries and be restored. Don’t sand it until it is dry and stable. If you use a polyurethane finish, search for one that is water vapor permeable.
Check inside exterior walls and attics for wet insulation. Remove and discard all wet fibrous or open cell foam insulation, even if it means cutting into wallboard. Saturated insulation will hold water, even if the wall looks dry, and eventually cause wood rot and mold problems. Flush out the insides of the walls with water to remove silt, then allow to dry thoroughly before installing new insulation. If possible, air condition and use a dehumidifier to speed the drying of materials.
Remove and discard vinyl wallpaper to allow sheetrock or paneling to dry inward. Refinish interior walls with latex paint (never use vinyl wallpaper) to allow the walls to continue to dry to the inside. However, a shellac based sealer may be needed over ceiling water stains before repainting.
Consider restoring your home with flood hardy materials that can withstand future flooding and need only cleaning. Choose ceramic tile, solid vinyl tile or solid wood flooring and elevate equipment, when feasible. If your flooded walls have solid wood studs and plywood or board sheathing, consider insulating with two inches of closed cell foam spray insulation or rigid foam boards, and finish with paperless drywall leaving gaps behind molding. After the next flood, you could then remove moldings, flush out the wall cavity and avoid having to gut and replace all the materials.