How to kill black mold

Remove the Source of Moisture

Any treatment will not prevent or remove mold till you permanently remove the source of mold which is moisture.

To stop the spores spreading to other areas in your home during cleanup, the area must be covered with plastic sheeting and also isolated from the rest of the space. It is best to cover the area so that mold spore can not migrate to the rest of the area. Try to cover all the area and walls with plastic sheets. You can also cover all the openings, windows, doors and vents with a plastic sheets to minimize the amount of mold spores that escape into the air.

dust mask

Protect yourself by wearing a dust mask and wear plastic or rubber gloves. It will irritate the skin and eyes so try to wear goggles and gloves. For very rare cases of black mold, the use of breathing respirator HEPA cartridges is recommended over the use of a simple dust mask. Do not use any fan or vacuum as this unfiltered air movement produced by these appliances can spread mold spores throughout the house.

Use HEPA vacuums as it contains filters designed to remove toxins and allergens.

Prepare your chemicals

For the surface mold, you need to have a bucket filled with a solution of bleach and the other bucket filled with a normal cleaning solution. It is best to use sporicide which is a biocide to kill mold presence in heavily affected areas. Allocate these solutions to separate bottles of spray.

Mix 8 oz (250ml) of bleach with (3.8L) 1 gallon (4L) tap water.

Fill another bottle of spray with a warm clean water.

Clean the visible mold with bleach solution

clean mold with brush

Drench the area from top to bottom. Scrub the area which is affected with disposable rags or paper towels.

Do not save or never reuse rag after using it for removing the black mold. Try changing the towels to prevent spreading mold spores from the towel back to the surface.

Discard the towels by throwing them in a large plastic bag.

Clean the area with bleach

clean area with bleach

Spray the affected area with your diluted solution of bleach and let it be there for 15 minutes before cleaning it away. Commercial fungicides used to treat mold or in addition to bleach. Use the fungicide after cleaning the affected area and always follow the instructions provided on the label when applying it.

Vacuum the area

After having a dry surface, use a HEPA vacuum to clean off the dead mold and spores.

Vacuum at least one minute on affected areas.

Dispose of the vacuum filters in a plastic bag. Throw out the bags.

Quickly do cleanup

Clean up your clothes and wash them. Flush any waste water down the toilet, sink or any floor drain.

Coat the affected area with Borax

Borax to clean mold

Mix (250ml) 1 cup with (3.8 L) 1 gallon (4L) hot water. When it fully dissolve, transfer the borax solution in a spray bottle and spray on the moldy area. After a few minutes scrub the mold with a scrubbing brush.

Do not rinse the borax away afterward

Create a paste of borax using a less amount of water then apply this paste to the moldy areas and wait for several  minutes. Scrub the paste using a scrub brush.

Borax is a white natural mineral powder and it is used as a fungicide as well as herbicide, disinfectant, pesticide and deodorizer.

Natural Remedies

Use a tea tree oil

tea tree oil

Mix 2 teaspoon (10 ml) tea tree oil with 2 cups (500 ml) water in a bottle of spray and shake it vigorously to combine. Spray it on affected areas.

Don’t rinse the solution off and let it immerse into the mold and apply again if necessary.

Tea tree oil is a little bit expensive and it has a strong odor but the smell would disperse within a couple of days.

Grapefruit seed extract

grape fruit seed extract

Put 20 drops of grapefruit seed extract with two cups of water in a spray bottle. Shake to mix it properly and apply to the contaminated area.

Do not rinse the solution off the surface.

Grapefruit is same as like the tea tree oil. It is also expensive and extracts last indefinitely. It is odorless.



Pour undiluted vinegar into a spray bottle  and spray it directly on to the black mold. Let it there without scrubbing or rinsing.

White vinegar has an ability to kill 80 percent of mold. Since the black mold is so hardy, it is best to use undiluted vinegar.

Remove mold using baking soda

baking soda

Mix 5ml baking soda with 2 cups (500ml) water in a spray bottle and shake rapidly to mix them together. Spray the solution on the area which is affected by black mold and scrub it with a scrubbing brush. Rinse with warm clean water.

After rinsing off the solution, apply baking soda solution again and let it dry. This will kill the remaining mold.

You can also use a baking soda with vinegar.

Apply hydrogen peroxide solution

Hydrogen Peroxide

Apply 3 percent of hydrogen peroxide on the black mold. Wipe it when done the cleaning.

Hydrogen peroxide can be severe, so the best way is to avoid letting it stay in the affected area.


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