After wood floors have been covered with wet mud and dirt, they need to be cleaned, flattened and possibly replaced, said Lois Warme, Iowa State University Extension art and design specialist.
“Cleaning is the first step to fixing flood-damaged woodwork,” Warme said. Before the house dries out, scrub all woodwork with a stiff, but nonabrasive brush, plenty of water and a non-sudsing detergent to remove mud and silt from corners, cracks and crevices.
Floodwaters may accumulate in partitions and exterior walls. Drain these areas as quickly as possible of insulation and structural members can dry. Remove the baseboard and drill holes between studs a few inches above the floor. After the insulation and frames have dried, replace the baseboard.
Use your regular cleaning product for a final, thorough floor washing. If refinishing is necessary, wait until moisture has dried from wood framing, between walls and floors, and backs of trim. This may take several months. Consult an experienced professional for refinishing, or follow instructions on standard brands of finishes and varnishes for household use.
Wood floors will probably be buckled, Warme said. Leave them alone to dry. Dry wood as fast as possible without aggravating shrinkage or deformation. Open windows and door wide enough to give good ventilation on dry, non-humid days. Maintain a temperature of 50 degrees to 60 degrees Fahrenheit or higher in the house.
After the house is dry, there are several possibilities for renovating the floors. Some of the buckled flooring may be pounded into place with nails. Some humps may be removed by planning or sanding. Heavily planed floors may never be used uncovered, but a smoothed old floor can serve as a base for a resilient hard-surface floor covering.
Mold and mildew are common problems with wet wood. Badly infected wood must be replaced, Warme said. Clean mildewed floors, woodwork and other wooden parts by scrubbing with a mild alkali, such as washing soda or tri-sodium phosphate, using four to six tablespoons for each gallon of water. Rinse well with clear water after scrubbing with alkali and allow the wood to dry thoroughly. Then apply a mildew-resistant finish.
To remove mildew stains or mold from unpainted wood surfaces, wash with warm soapy water. If stains remain, add one-half tablespoon of tri-sodium phosphate or four tablespoons of borax to each gallon of warm soapy water. Dry by rubbing with an absorbent cloth.
If mold has grown into the wood under paint or varnish, the finish must be removed. Scrub the wood with an abrasive cleaner, then wash with a solution containing four to six tablespoons of tri-sodium phosphate and one cup of household chlorine bleach for each gallon of water. Sand the wood and bleach any remaining spots. Several applications of household bleach may be needed. Then wash the surface with a weak ammonia solution—two tablespoons of ammonia per quart of water. Finally, rinse the wood well with clear water. Let wood dry thoroughly and apply a wood preservative before repainting or refinishing.
Source: Iowa State University Extension Service