Wood easily absorbs liquid, especially water. As a result, wood is an ideal home for mold and mildew caused by insufficient ventilation or dampness. Mold normally appears in greenish-brown or black patches.

Mildew is the term prevalently used to associate mold fungi and the discoloration found on wood surfaces. Aside from the unpleasant appearance, mold spores may cause allergies and other health issues.

Before removing mold from your wooden surfaces, make sure to prepare the basic tools and supplies.

You need the following supplies:

  • water
  • bleach
  • baking soda 
  • household detergent
  • sandpaper
  • wood cleaner

Optional:

  • baking soda
  • vinegar (in case this is preferred to bleach)
  • commercial removal product

Tools needed:

  •  air mask or respirator (N95 is recommended)
  • rubber gloves 
  • protective clothing or coveralls
  • vacuum (use a HEPA filter)
  • safety goggles
  • scrub brush with soft bristles
  • sponge
  • soft cloth 

Here are the steps to remove the mold that has grown on wood:

Step 1: Choose the Right Cleaning Solution

There are several commercial products available to address mold issues. These are premixed so you don’t have to go through the process of mixing different solutions. However, make sure that you use the right cleaning solution to address your unique mold problem. For instance, in getting rid of fungus from painted or finished wood, mild cleaning solutions are great options. There is no need to kill the mold, just remove it. But for unfinished wood, mold typically penetrates below its surface, the solution has to be stronger to kill the culprit.

Here are suggested solutions for finished and unfinished wood:

Finished or painted wood

  • distilled vinegar
  • baking soda, household detergent and water (1 cup of water, 1 tablespoon of liquid detergent and ½ cup baking soda)
  • warm water and liquid detergent mixture
  • premixed or commercial mold removal product

Unfinished wood:

  • warm water, Bleach and detergent solution (20 parts of water, 10 parts of bleach and 1 part liquid detergent)
  • Sodium borate or Borax and water (1 part of sodium borate and 16 parts of water)
  • Distilled vinegar
  • Rubbing alcohol
  • Premixed or commercial mold removal product

Please be aware that bleach is not absorbed by the wood. It only inhibits or kills mold spores that appear on the surface of the wood. You should use commercial products for mold that is inside the wood, as those products have additives that allow absorption into the wood fibers. This additive is called surfactant.

Step 2: Wear Protective Clothing and Gear

Make safety measures

Regardless of the condition of mold spores and the severity of the chosen cleaning solution, do not be complacent. Always take safety precautions and wear a protective suit and gear. Mask, rubber gloves, goggles or glasses, and coveralls or protective outerwear are a must.

A mask or respirator will prevent mold spores from entering your lungs. Rubber gloves will protect your hands from skin irritation. You should also wear goggles to protect your eyes from any particles. Finally, if you are sensitive to mold exposure, you should wear a protective suit. However, for severely sensitive people, hiring someone to perform the task is the best idea. Finally, the room should have adequate ventilation if you are using chemicals with strong fumes to treat the mold.

Step 3: Vacuum the Affected Area of Wood

A vacuum with a HEPA filter is the best recommended tool to suck up all loose mold spores together with other accumulated dirt and debris. Once removed, empty and clean the dust bag or canister. The vacuumed dust should be disposed of properly so that no spores will escape and spread.

Step 4: Clean off the Mold With Soap and Warm Water

If the wood is painted or finished, it is best to use a mixture of water and liquid detergent to clean the moldy area. Use a soft-bristled scrub brush in cleaning the affected area. Make sure not to overdo the brushing unless you want to refinish the surface. If you are not satisfied with the results, you may opt for distilled vinegar. You can also apply vinegar by using a spray bottle. Let it sit for an hour and wipe the surface with a damp clean cloth. Check the surface and if you are certain that it is mold-free, wipe it with a clean towel or rag.

If chlorine bleach is used, it has to be diluted with water and liquid detergent. Mix one part liquid detergent with 10 parts chlorine bleach and 20 parts warm water. Use a soft-bristled brush and let the solution air-dry.

The solution has to be applied lightly, but sufficient to cover the mold. Too much solution can cause dampness or moisture which is the main reason for the growth of mold.

Ste 5: Use Bleach For Tough Mold Stains

Some stains can be removed by using vinegar. Others are quite difficult to deal with. If the mold stain still won’t come up, it is time to use a stronger solution which — is bleach. Bleach has multiple uses in this situation. It can be used to kill the fungus that has established beneath the wood surface, and also as a strong agent to remove tough mold stains. Mix one tablespoon of detergent, ½ cup bleach and one cup warm water. Apply on a stained area with either a scrub sponge or a soft-bristled brush and let it dry. 

Step 6: Sand the Area if Needed

A stubborn mold may remain even after scrubbing. In this case, sanding is the last resort. Sanding is the only way to penetrate the mold beneath the wood. However, you cannot use just any sandpaper available. Use a fine grit sandpaper, 100 to 200 rating. Run the sandpaper slowly around the moldy area until the unsightly appearance disappears. It is recommended to sand the area while it is still damp to prevent mold spores from spreading. After sanding, vacuum the affected area to remove mold spores, dust and debris.

Step 7: Refinish or Re-apply Protective Wood Coating If Necessary

Sanding can destroy the appearance of the wood surface. You may consider refinishing or re-applying the lacquer, polyurethane, proactive stain or any other finishing product of your choice or that was on it.

Editorial Contributors
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Matt Greenfield

Matt Greenfield is an experienced writer specializing in home improvement topics. He has a passion for educating and empowering homeowners to make informed decisions about their properties. Matt's writing focuses on a range of topics, including windows, flooring, HVAC, and construction materials. With a background in construction and home renovation, Matt is well-versed in the latest trends and techniques in the industry. His articles offer practical advice and expert insights that help readers tackle their home improvement projects with confidence. Whether you're a DIY enthusiast or a seasoned professional, Matt's writing is sure to provide valuable guidance and inspiration.

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