Does Bleach Kill Mold?

Mold Restoration

For a long time, common household bleach has been a go-to product for fighting mold. It’s true that bleach is a sanitizer that eliminates viruses and bacteria, but does bleach kill mold?

While bleach can kill mold on hard surfaces, it’s ineffective when used on softer surfaces, which is where you’ll find the most mold. Plus, bleach may harm your health, as well as the surfaces you treat. Even The EPA does not recommend using bleach as a routine practice to kill mold. 

This blog will detail more reasons why your PuroClean mold remediation specialists do not recommend bleach for mold remediation and some alternatives you can safely use instead. Keep in mind: if you have a serious mold problem affecting an area larger than 10 square feet, reach out to PuroClean immediately for professional and dependable service.

What is Mold and Why is It Dangerous?

Mold is a form of fungus that can range in color from white or gray to black. Its texture can vary, too; some mold species are furry and resemble the surface of rocks, while others look slimy like jellyfish. Mold reproduces by spores which scatter through the air and cause new colonies to grow.

black mold in corner of wall. Does bleach kill black mold?

Mold can trigger adverse health effects in humans. Symptoms include watery or red eyes; coughing, wheezing, tightness of the chest, and difficulty breathing; skin irritation like itching, rashes, and blisters; nasal stuffiness; chronic fatigue syndrome symptoms like headaches, body aches, fever, chills, saliva that is thick, discolored mucus, nausea or vomiting. If you experience any of these symptoms while dealing with a mold infestation at your property, seek medical attention quickly.  

Why is Bleach Ineffective Against Mold?

Although many people use bleach as their go-to to kill mold, it is not the most effective. Bleach is not effective because it cannot penetrate porous surfaces to kill mold spores. Mold can grow on almost any surface found around your house, even where you can’t see it. These include drywall interiors and exterior walls, wood trim and cabinets, insulation inside walls, ceiling tiles, wallpaper, carpeting, etc.

Bleach also evaporates quickly from treated surfaces. After a couple of hours, it becomes ineffective against mold growth, leaving you to think that it’s been eradicated when in fact, the mold spores are still present. 

  • Bleach is ineffective at killing mold on many non-porous materials like drywall, wood, and carpet. In the case of these softer materials, mold spreads deep into the porous surface. The nature of bleach prevents it from soaking into these materials, so only the surface mold growing above is killed. Bleach won’t kill mold on dirty and metallic surfaces, either.
  • Bleach contains a lot of water and may stimulate mold growth if you use it to kill mold on soft materials. Once you apply bleach to mold on a porous surface, the chlorine content of the beach dries up almost immediately, and water in the bleach is absorbed by the material, feeding the mold that survived inside it. The water travels down to the root of the mold and helps it thrive. As a result, mold may regrow on the surface within a week or two if the material isn’t dried properly. You can thus end up in a cycle of repeatedly trying to bleach mold, only to have it persistently return. 
  • Not only is bleach ineffective against mold on wood, but it’s also corrosive and extremely harmful to these materials. Wood that is treated with bleach becomes weakened by breaking down its fibers. This can compromise the structural integrity of your home.
A bottle of bleach that many people use to kill mold - but does bleach kill mold?
  • Bleach cleaners lose their power with time – it is up to 50% less effective in 90 days, even if its container is not opened.
  • Using bleach can damage your health. Bleach can give you burns if it touches your skin, and the gas from bleach can harm your lungs. Contact with eyes may cause pain and irritation. Bleach can also damage the eye tissues if it stays for a longer time.
  • Dead mold may still cause allergic reactions in some people. Thus, it’s not enough to simply kill the mold; you must also remove mold.

The Dangers of Bleach

Bleaching is an outdated practice for eliminating mold (not to mention one that doesn’t work). Some people believe using bleach has health benefits, but it actually increases the likelihood of respiratory problems and skin irritations. 

Because of the dangers of mold, you should always wear proper PPE (Personal Protective Equipment). This includes goggles/eye protection, gloves, and N-95 masks. If you decide to use bleach against mold, make sure you also wear protective clothing and open windows for ventilation once you complete the job — remember that bleach lasts long after it dries!

Bleach is corrosive, so it will bleach the color out of almost any surface you use it on. It can harm wood and cause discoloration on some walls and fabrics. Bleach also kills your grass if you spill it on the ground, so think twice before using this product in places where children or pets play.

What to Use Instead of Bleach Against Mold

The best step you can take for mold removal is calling your local PuroClean. Our professional technicians have the best equipment, knowledge, and tools to protect your home and family. 

If the mold affects a surface area smaller than 10 square feet, there are some household products you can choose to use to remove mold growth. It is important to keep in mind that these are not the same solutions or processes the professionals would use. Always wear proper PPE when cleaning mold. Baking soda, vinegar, and hydrogen peroxide are all excellent mold-killing solutions. 

1. Baking Soda

Mix equal parts baking soda with water to create a paste. Apply the paste to the moldy surface and let it sit for at least 15 minutes before rinsing it away with warm water. Repeat if necessary to remove all the mold.

2. Vinegar

Mix white vinegar with water in a 1:3 ratio in a spray bottle. If you have mold growing on wood, use undiluted vinegar. Spray the vinegar mixture to the affected surface and let it sit for at least 15 minutes before rinsing it away with warm water. Repeat if necessary. 

3. Hydrogen Peroxide

Mix hydrogen peroxide with water in a 1:4 ratio. Apply the mixture to the moldy surface and wipe it away with a damp cloth. Spray undiluted hydrogen peroxide on moldy surfaces, making sure it soaks into porous materials. Let sit for 10 minutes, then rinse thoroughly.

Don’t Trust Bleach to Kill Mold – Call PuroClean 24/7 for Effective Mold Remediation!

Does bleach kill mold? The short answer is no; bleach is not effective for mold removal. If your home is infested with mold due to water damage, you may be tempted to use bleach as an easy-to-find household product. However, don’t risk the health of your family by using bleach against mold – it will not kill mold and could actually make a bad situation worse.

PuroClean technicians are trained and certified to handle your toxic mold growth safely and effectively. Our teams are equipped with the safest, most effective products on the market to remove mold and clean your home or business. To find out more about how PuroClean can help you with mold remediation, visit our website or call (800) 775-7876 to get connected with your local PuroClean office.

Last edited on 17th of March 2022