Mold and mildew are a common problem for outdoor furniture, or furniture in a dank environment, like a basement without a humidifier to remove moisture from the air. Mold is a toxic substance that can cause serious health problems, and mildew stains leave unpleasant discolouring on furniture. Sometimes porous wood furniture, such as maple, can become ruined if not properly cleaned to remove mould and mildew.
Clean mould and mildew from wood furniture with common household ingredients. Fill a bucket halfway with cool water. Mix 2 capfuls of bleach in the water. Put on disposable plastic safety gloves and a chemical fume mask to protect against bleach fumes. Wear these items throughout the entire process. Take the furniture outside or if inside, properly ventilate by opening up windows. Spread a tarp on the floor around or under the furniture to protect flooring from bleach.
Soak a scrub brush with strong bristles in the water with the bleach. Then begin scrubbing the mildew stains with the scrub brush. If the mildew doesn't lift easily, wait 10 minutes and scrub again, this time using a bit more bleach.
Fill a bucket with clean water. Add a generous capful of mild dish detergent, something with disinfectant properties. Soak a scrub brush in the soapy water and then begin re-scrubbing the furniture. Use a mild alkali, such as trisodium phosphate, if mild detergent doesn't work. Use 8 to 10 tbsp to 1 gallon (5 litres) of water. Scrub the trisodium phosphate and water mixture on the furniture; then rinse clean.
Apply wood cleaner made for removing mould and mildew from wood furniture with a clean scrub brush. Scrub away the mould and mildew, careful to rinse the brush in a utility sink as you clean, to eradicate the mould or mildew, and not spread it around. Repeat as necessary until there are no traces of mould or mildew stain left on the wood furniture.
Remove bad or excessive mould from wood furniture by stripping the furniture. Depending on how bad the mould is, scrubbing mould might release dangerous mould spores into the air. Restore the furniture where the mould and mildew is to completely eradicate the mould and mildew growth.
Use a chemical stripping agent. Paint the chemical stripping agent over the mould with a paintbrush. Before the chemical stripping agent fully dries, take a putty knife or sharp scraping tool, and in one motion, scrape or lift the mould away. Dispose of the mouldy section immediately in a plastic garbage bag and then seal the bag.
Go over the newly stripped sections of wood furniture with an electric sander or 320-grit sandpaper to even out the grain and restore the surface after scraping. Remove wood dust with a paintbrush.
Stain wood in a waterproof and mould-proof stain of your choice. Take a clean paintbrush and dip it into the stain. Apply in even strokes. Remove excess stain with a dry rag. Seal the wood with a gloss varnish that prevents future mould or mildew growth. Use a clean paintbrush and apply evenly. Paint a second coat, if needed. Wait for the first coat to dry before applying the second.