How To Clean Mold and Mildew from Wood
High humidity, prolonged exposure to moisture, and water intrusion from natural disasters and burst pipes can all result in water damage to the wooden objects, furniture and surfaces of your home. Even though the health concerns associated with mold, mildew and decay fungi supercede aesthetic concerns, cleaning materials and application methods can be tested in an inconspicuous spot before treating a wider area to help ensure desirable results.
While some household molds may cause mild irritation, others may cause serious health issues. Work in a well-ventilated area, or ideally move the object outside for cleaning. The use of additional gear such as a filtered respiration mask and other protective gear will help facilitate a safer, less irritating clean-up.
For green or black mold/mildew residue
Loosen and brush away as much bulk organic stain material as possible using a soft synthetic bristle brush that can be easily disinfected or disposed of. There may still be stubborn mold and mildew residue that is adhering to the surface. Lubricate the residue with 1 tsp of glycerin. Mix about 1 quart of cleaning solution at a time using 1 quart of water and 1/4 cup of borax - which will help act as an anti-fungicide. Scrub the lubricated stain with the water/borax mixture, again using the brush. Rinse the brush regularly, refresh the cleaning solution as necessary, and keep paper towels on hand to periodically blot excess moisture and help prevent potentially damaging overwetting. Allow the affected area to dry thoroughly, and follow with an overall buff and polish with a soft clean cloth and the appropriate paste wax or polishing compound.
For brownish decay fungi
Wood decay is a type of damage that requires removal as opposed to remediation. The discolored wood must actually be removed, as well as a perimeter around the visibly damaged area. A curved blade (reminiscent of a grapefruit knife, but without the serrated edges) can be used to carefully scoop out the decayed wood. If you don't have, or don't wish to purchase a specialized tool, you can substitute a fine-grit sandpaper. Work gradually, periodically brushing away the loosened decay with a clean rag lightly dampened with a cleaning solution made of 1/4 cup of borax to 1 quart of water. The final layers of decay and the surrounding perimeter can be lightly sanded away, until completely unaffected wood appears in the bottom, sides and perimeter of the affected area. Clean the area well, and completely remove the fungal residue with a clean cloth lightly dampened with the water/borax solution. Allow the area to dry thoroughly before treating the resultant depression with the techniques for gouges and dents described in this section.
If the resultant depression is too big for moderate repair, it can be patched with actual wood. Use a type of wood that matches the object being repaired. Cut and/or shape the wood to fit the missing area. Attach the wood to the dry, clean surface using a stainable wood glue. Allow to dry/cure thoroughly, clamping or otherwise securing the repair as necessary to help ensure a clean repair. Stain the patch piece and glue with a color closely approximating the rest of the surface. Err on the side of using a slightly lighter stain than the surrounding surface as the stain may darken as it dries, and it will be far easier to deepen a stain that is too light than it is to lighten a stain that is too dark. Allow the stain to dry according to manufacturer's instructions, usually allowing at least 24 hours. The repair can be further blended into the greater area with a light overall polish and buffing. Remember that the goal is to alleviate the disruptive appearance of the patch repair. With an eye for detail and intimate knowledge of your own furniture and surfaces, you may always be able to single out a repaired area that a casual or objective observer may not be able to see.
Caution: Never mix cleaning agents or chemicals, the result can be dangerous or deadly. Before cleaning, always test the agent on an inconspicuous location to determine its suitability and to make certain it does not damage the material. Wear appropriate clothing such as gloves and protective eyewear, and work in a well-ventilated area. Accidental inhalation or ingestion of cleaning agents can be hazardous and even fatal, particularly to pets and children.