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Borax has many natural household uses such as killing allergens like dust mites to getting rid of mold and mildew. It is a natural cleaning agent that’s safe (except when ingested), so you can leave it on surfaces to get rid of mold, mildew, and odors in the house. How do you use borax to remove mold and mildew?
Borax kills mold by increasing the pH to inhibit its growth. Mix 1 cup of borax with 1 gallon of water then sprinkle the solution on the moldy surface. Scrub off the mold using a cleaning pad. Allow the borax solution to sit for 2 hours before rinsing with distilled water to remove all the mold.
Does borax kill mold?
Borax kills mold by inhibiting its growth and spore production. It works as a contact fungicide and can be used for cleaning moldy surfaces including wood and metal.
Mold thrives in acidic environments with a pH range of 3.5-8.0. Borax has a pH level of 9.13 and introducing it increases the pH level of the medium in which mold grows. This kills mold and inhibits the germination of their spores.
Apart from killing mold, borax can also get rid of mildew and its odors in the house by creating an alkaline environment that’s not conducive for the fungi to grow and thrive.
Use borax to clean areas that are always damp, dark, and susceptible to different types of mold and mildew.
How to Kill Mold with Borax
Borax is packaged in a powdery form and you can buy it at your local grocery store. You can also buy it on Amazon and have it delivered directly to you. To use borax to clean mold, mix it with water to make a borax solution for wiping moldy surfaces.
Here’s how to kill mold with borax:
- Add one cup of borax into a bucket.
- Pour 1 gallon of hot water into the bucket.
- Mix thoroughly to make a borax-cleaning solution.
- Wear safety gloves and sprinkle the solution on the moldy surface.
- Scrub off the mold with a brush or a cleaning pad.
- Allow 2-3 hours for the borax to disinfect the surface effectively.
- Rinse the surface with clean distilled water.
If you do not want to leave the borax solution on your surfaces, rinse it off and repeat this procedure for 2-3 days to make sure all the mold spores are eliminated.
Borax and vinegar for Killing Mold
Vinegar is a common household item that’s acidic in nature. Since it is used for cleaning many surfaces safely, you might think of mixing it with borax to make a more potent solution for cleaning up mold.
But, can you mix borax and vinegar to get rid of mold?
Do not mix vinegar with borax to make a mold-killing solution. Borax is alkaline while vinegar is acidic. Mixing the two will cancel out the cleaning power that’s in each of them, making the mixture less effective at getting rid of mold on surfaces.
If you want to make your cleaning solution more potent for getting rid of mold, you can add alkaline solutions, or use borax as it is because it is effective especially if you don’t over-dilute it with water.
Borax and hydrogen peroxide
You can mix borax with hydrogen peroxide and distilled water to make a mild solution for cleaning up moldy areas. You can also spray the solution on clothes that can easily grow mold – such as workout outfits.
Some sources say that mixing borax with water produces hydrogen peroxide that’s highly acidic and can cause damage to metal surfaces and even clothes.
To take precautions, use a low concentration of hydrogen peroxide for this mold treatment to prevent damage to your clothes, wooden, and metallic surfaces.
Bleach vs Borax for Killing Mold
Both bleach and borax are great for killing mold, but there are pros and cons to each. Borax is a natural mold killer while bleach contains chemical compounds that release toxic gases into the environment.
So, which one (bleach or borax) is a better mold disinfectant?
Both solutions work as DIY mold killers and can be used almost in a similar way. If you don’t have a mold killer yet there’s borax or bleach in your pantry, simply use one as an alternative.
To use bleach to get rid of mold and mildew in bathrooms and other places in your house, Add one cup of bleach to one gallon of water. Sprinkle the solution onto the surface with mold and scrub with a soft-bristle brush. Leave the solution to sit for 2-3 hours before rinsing it off.
Pro tip: If you use borax and bleach, you might want to run an air purifier for 24 hours to get rid of the toxic fumes that bleach emits in the house.
Where to use Borax for mold
While borax is a great mold eliminator, you might want to be careful where you apply it to kill mold. If you have indoor plants with signs of mold growing on the surface of their potting soil, you should not apply borax as it can alter the pH of the soil.
In addition, do not use a borax solution to clean mold on porous surfaces such as drywall ceilings and walls. Such surfaces are absorbent and can retain moisture that can worsen your mold problem.
Here’s where you can use borax as a cleaning agent to get rid of mold safely:
Cleaning Mold on Basement Walls
Basements are notorious for attracting mold because of the high humidity coming from walls and underlayment in their flooring.
If the basement foundation walls are moldy, add one cup of borax into a bucket of hot water. Scrub out the mold on the walls of your basement floors and walls using a stiff brush. Leave the solution on the surfaces without rinsing to prevent mold spores from growing on the surfaces.
Cleaning clothes
Borax is great for getting rid of acidic stains from clothes because of its alkalinity. If you add it to your laundry, it will also help get your white clothes whiter.
Another important benefit of borax is killing mold spores in your clothes. It is, therefore, best used for clothes that contain a lot of sweat especially if they remain damp for some time before being washed.
Pro tip: You can use borax as a pre-treatment solution for your clothes. Simply soak them with a little borax before putting them in your laundry machine.
Moldy bathrooms
Bathrooms grow mold because of the high humidity in the atmosphere. If left uncleaned, mold and mildew can grow on various surfaces such as ceilings, walls, and corners of the bathroom.
To clean up mold in the bathroom using borax, mix one cup of borax with a bucket of water. Scrub the surfaces with this solution and leave it for 24 hours for the mold spores to die.
How long does it take borax to kill mold?
Borax changes the pH of a moldy environment. Doing so inhibits the growth of mold spores in your house. You can leave borax on surfaces for 24-48 hours to kill mold and prevent spores from germinating.
You can also prevent mold and mildew by running a dehumidifier in the house to reduce atmospheric moisture that contributes to the mold problem.
READ NEXT: How to Deal with Black Mold on Wooden Furniture
References
- Ted Gordon, Mississippi State University Extension: Safety Tips – Combating Black Mold
- National Institute of Environmental Health Sciences: Mold Remediation Guidance
HVAC tech with over 30 years of experience. Retired and doing repair work on the side around Madison County, AL.