How To Kill and Remove Mold
Mold Killing Products
There are several products and solutions you can use to kill and remove mold. Some effective mold killing products include:
- Borax
- Bleach
- Vinegar
- Ammonia
- Hydrogen peroxide
- Detergent
- Baking soda
- Tea tree oil
- Grapefruit seed extract
For a step by step guide to the entire mold removal process covering protective equipment, containing spores, killing the mold, preventing the mold's return, mold disposal and final clean up go to Mold Removal and Clean Up
To find out how to remove mold from your clothes go to
Mold On ClothesBorax
Does Borax Kill Mold?
There are many advantages to using borax to kill mold. For starters, borax is a natural cleaning product and although it is toxic if you swallow it, borax does not emit chemicals or dangerous fumes like some other mold killers. Borax, a white mineral powder, has a pH level of about 9 (baking soda is pH 8.1 and pH 7 is neutral) and a low toxicity.
Borax is commonly used as a deodorizer as well as for cleaning toilets and drains. Borax is also used as an insecticide, herbicide and fungicide and it can be mixed with water in a solution to kill and remove mold as it is a natural mold inhibitor. You can buy borax in supermarkets for a few dollars from the laundry section.
How to Kill Mold with Borax
- To kill mold using borax, create a borax-water solution using a ratio of 1 cup of borax per gallon of water.
- Vacuum up any loose mold with a HEPA filtered vacuum cleaner to lessen the number of spores stirred up into the air during the cleaning process.
- Use a scrubbing brush with the borax-water solution to scrub the mold off the surface.
- Wipe up any extra moisture and excess mold particles or dust/debris to prevent them spreading into the air once the surface has dried.
- You don't need to rinse off the borax as the solution will prevent more mold beginning to grow on the surface again.
- Leave the surface to dry completely.
Bleach
Bleach & Mold
Bleach can kill virtually every species of indoor mold that it comes into contact with, along with its spores, leaving a surface sanitized and resistant to future mold growth. Unfortunately, however, using bleach is only effective if the mold is growing on non-porous materials such as tiles, bathtubs, glass and countertops. Bleach cannot penetrate into porous materials and so it does not come into contact with mold growing beneath the surface of materials such as wood and drywall. Using bleach on these materials will kill the mold above the surface but the roots within the material will remain and the mold will soon return.
How to Kill Mold with Bleach
- Bleach produces harsh fumes so make sure the area is well ventilated before you begin. You should also wear gloves during the process to protect your hands.
- For killing mold with bleach use a ratio of one cup of bleach per gallon of water (ie about 1 part bleach to 10 parts water).
- Apply the solution to non-porous surfaces with mold growth either by using a spray bottle or by using a bucket and a sponge or cloth.
- You don't need to rinse the surface afterwards as the bleach will inhibit mold growing in the future.
Arguments Against Bleach
Although the active ingredient in bleach, sodium hypochlorite, is the main ingredient in many mold killing products such as "Exit Mold", there are many reasons to use alternatives to chlorine bleach when killing mold.
One reason is that bleach cannot completely kill mold growing in porous materials. The chlorine in bleach cannot penetrate into porous surfaces such as drywall or wood. The chlorine is left on the surface of porous materials and only the water component of the bleach is absorbed into the material, providing more moisture for the mold to feed on. Some of the mold on the surface might be killed but the roots of the mold are left intact meaning the mold soon returns, leaving you in a cycle of repeated bleaching. Perhaps this is why some people believe that spraying bleach on mold doesn't affect it but instead just bleaches its color so you can no longer see it.
Another disadvantage of bleach is that it can damage the materials it's used on as it is a harsh, corrosive chemical. Chlorine bleach also gives off harsh fumes and it even produces toxic gas when mixed with ammonia. There are safer alternatives such as borax or vinegar which don't produce dangerous fumes or leave behind toxic residue. For these reasons try to avoid using bleach and if you must use it, only use it on non-porous surfaces.
Vinegar
Vinegar Kills Mold
Vinegar is a mild acid which can kill 82% of mold species. However it also has the advantages of being natural and safe. Vinegar is non-toxic and doesn't give off dangerous fumes like bleach does.
How to Kill Mold with Vinegar
- To kill mold with vinegar, use white distilled vinegar which you can buy cheaply from the supermarket.
- Pour some vinegar into a spray bottle without watering it down.
- Spray the vinegar onto the moldy surface and leave it to sit for an hour.
- Wipe clean the area with water and allow the surface to dry. Any smell from the vinegar should clear within a few hours.
If you want to use vinegar to prevent mold growing on surfaces just spray vinegar on the surface and leave it. Repeat this every few days to ensure the surface will stay mold-free. You can even mop your tiled bathroom floor or other hard non-porous floors with vinegar if you are worried about mold growing on them.
Ammonia
Does Ammonia Kill Mold?
Like bleach, ammonia will kill mold on hard non-porous surfaces such as countertops, glass or tiles but it is ineffective at killing mold growing in porous material such as wood or drywall.
Another disadvantage of using ammonia is that it is a harsh, toxic chemical. Make sure you never mix ammonia with bleach because the gas they create when combined is toxic. Chlorine mixed with ammonia was even used as a chemical weapon during World War 2.
Additionally, although ammonia can kill surface mold, dead mold and dead mold spores are still allergenic so you will need to make sure to remove them afterwards.
How to Kill Mold with Ammonia
- To kill mold using ammonia, create a solution of 50% clear ammonia and 50% water in a spray bottle and spray it on moldy areas.
- Make sure the ammonia you use says "clear ammonia" on the label.
- Leave the area for a few hours before wiping and rinsing.
- Often detergents or mold cleaning products will contain ammonia. In that case just follow the directions on the label and be sure never to mix it with bleach.
Hydrogen Peroxide
Hydrogen Peroxide and Mold
Hydrogen peroxide kills mold as it is anti-fungal as well as anti-viral and anti-bacterial. Hydrogen peroxide is a good alternative to chlorine bleach because it is safe to use and doesn't damage the environment, nor does it leave behind toxic residue or produce toxic fumes like chlorine bleach does. You can buy hydrogen peroxide from drug stores for around one dollar for a bottle of 3% concentration.
Hydrogen peroxide kills mold effectively on many materials such as clothes, floors, bathroom fixtures, walls and items such as kitchen appliances. Since hydrogen peroxide is a bleaching agent it may also help fade the stain mold leaves behind. Spot test hydrogen peroxide on the material you're going to be cleaning to make sure it won't fade the material's colors.
How to Kill Mold with Hydrogen Peroxide
- To kill mold pour 3% concentration hydrogen peroxide into a spray bottle.
- Spray the moldy surface completely so that the moldy areas are saturated with hydrogen peroxide.
- Leave the surface to sit for 10 minutes while the hydrogen peroxide kills the mold.
- Then scrub the area to make sure to remove all the mold and mold stains.
- Finally wipe the surface down to remove residual mold and spores.
You can also use vinegar with hydrogen peroxide during the cleaning to more effectively remove the mold. Afterwards store the spray bottle in a dark place since light diminishes hydrogen peroxide's effectiveness.
Detergent and Water
Removing Mold with Detergent and Water
A solution of detergent and warm water can be used to scrub surface mold off non-porous surfaces. Although detergent itself doesn't kill mold, if the mold is on non-porous materials then the solution doesn't need to kill it as long as you completely clean away all the mold on the surface.