How to Clean Mold on Varnished Panels

Dry the varnished panels. Wood panels are porous and you cannot dry them by simply wiping them with a towel. Place a portable heater or a dehumidifier near the panels and turn it on until the wood dries. If you have neither of these machines available, turn on your central heater. This method will take slightly longer.

Vacuum the varnished panels with a hand-held vacuum. If you have no hand-held vacuum, use a floor vacuum with a hose extension. Draw the spores out using the vacuum cleaner. In some cases this will completely resolve the problem. If you still see mold stains, proceed to the next step.

Scrub the varnished panels with a damp sponge containing only water and mild detergent. Use only a drop of detergent per cup of water, and wring out the sponge before scrubbing. Too much water can saturate and consequently damage the wood.

Pour a cup of household bleach and 10 tbsps. of trisodium phosphate into a gallon of water and mix. If all of the above methods fail to kill the mold, the problem likely exists beneath the varnish surface. Find trisodium phosphate at your nearest home supply store.

Scrub with your bleach and phosphate solution. Use a sponge to apply the solution to the panels, but avoid using too much moisture. After removing the mold, wipe the panels again to remove the chemicals. Dry the panels a second time.

Apply a new coat of varnish. The bleach and phosphate will remove much of the original varnish, but this was necessary to reach the mold trapped beneath. For best results, paint over the panels with a coat of thinned varnish, wait until it dries, and then paint with a coat of full strength vanish.