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What Kills Mold in the Crawl Space of a House?

Kaye Wagner

Mold is a variety of fungus that tends to grow in areas of your home with excess moisture and humidity, such as a basement or crawlspace. This is because without proper ventilation moisture can easily settle in the crawlspace. Once there, mold can grow on the wooden supports, walls and ceilings in your crawlspace. It can also grow on insulation. This can encourage mold growth in the rest of your home, make your home smell musty and eventually decay the crawlspace surfaces.


Bleach is a strong chemical solution that will kill mold in your crawlspace. Because it can irritate your lungs, skin and eyes, put on gloves, goggles and a dust mask whenever you use it. Mix 1 cup of bleach with 1 gallon water. Pour some of the solution into a spray bottle and spray it over all of the mold growth on the walls, ceiling and supports in the crawlspace. Let the solution sit for 10 minutes before scrubbing it off and wiping it up with a clean cloth. Bleach is a comparatively cheap cleaning solution for killing mold.


Ammonia is another chemical solution that will remove mold spores from the surface of the crawl space without damaging the wood. Never mix ammonia with bleach or use it on an area that was recently cleaned with bleach, as this results in a toxic gas. To use ammonia, pour a 2-percent dilution in a spray bottle. Spray it over moldy surfaces and let it sit for several minutes before scrubbing it up. Rinse the area with clear water and dry it completely.

Hydrogen Peroxide

Hydrogen peroxide is a chemical that will kill mold spores growing in the crawlspace. It will also kill bacteria and viruses on the surfaces that it comes into contact with. To use it, pour 3-percent hydrogen peroxide in a spray bottle and spray it over the mold growth. Let it sit until it is loosened from the surface. Scrub the area clean with a scrubbing brush and rinse completely. Wear gloves, goggles and a dust mask to protect yourself from the chemical and the mold spores.

White Vinegar

White vinegar is a natural disinfectant that will remove a large percentage of bacteria, viruses and mold spores. It is completely natural and non-toxic. To use it, fill a spray bottle with the white vinegar and spray it over the surface of the mold. Scrub the mold off and wipe it up with clean cloths. Let the white vinegar dry on the surface to prevent more mold from growing there.