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How Long Does Black Mold Take To Grow?

By April 10, 2023April 12th, 2023Mold
Black mold can grow very quickly under the right conditions.

When it comes to owning a home, the last thing any homeowner wants to see is mold. There are a variety of molds that can occasionally pop up during moist and high-humidity conditions. However, if you come across black mold, this is can be alarming. Black mold is very toxic and health-harming. How long does black mold take to grow? Black mold takes 24 to 48 hours once water damage has occurred. Within 12 days mold can be an issue.

Let’s take a look below at what we can do to prevent mold and how you know if it is mold.

What Is Mold?

Believe it or not, mold occurs naturally on Earth. It is an organism that is a part of the fungi family. Mold is known to grow inside or outside a home. The color type of mold determines how risky it is to your health. The most harmful mold colors are black, green, and yellow. Mold colors can show up as pink, purple, orange, blue, green, brown, and black. Mold will grow after water damage has occurred.

Identifying mold in your home requires immediate attention. Mold spores travel in the air and will settle in any area that has a high food source, such as moisture and humidity. Homeowners often find mold in their shower and bathroom spaces due to the high moisture in the bathroom. Mold exposure can be bad for your immune system.

Black mold is very toxic and should be immediately removed.

What Types Of Mold Are There?

As stated above, there are a variety of mold colors. Let’s take a look at the ones that you will typically see growing on a surface in or around your home.

  • White – Homeowners often find white mold in their basements or damper areas. Spray the location with water to determine if it is mold or a mineral deposit. If the water spray dissolves the white powdery substance, it is not mold.
  • Green – Also found in the dampest areas of your home. Homeowners will often identify this mold in the dampest corners of their walls.
  • Blue – Just like green mold, blue is also found in the dampest parts of the home. Homeowners will often identify this type of mold in the ceiling or walls of their bathrooms.
  • Black – Black mold is the most toxic mold that could be found in a home. Due to the production of mycotoxins, this mold can become deadly. If you discover black mold, it needs to be removed immediately.

How Does Mold Grow?

Mold grows when it has access to food like moisture and humidity. Excess water that enters your home through the foundation or other cracks and crevices can promote mold growth. When moisture levels in your home are increased, mold spores will settle on those spots and begin to reproduce. Within 24 to 48 hours you can see an outbreak of mold. Let’s take a look below at what else contributes to mold growth.

  • Organic surfaces – When organic materials such as paint on your walls are used, the surfaces provide a feeding source to mold.
  • Humidity – Allowing your home to stay at humidity levels higher than normal can create an increase in mold-growing possibilities.
  • Ventilation – Open up your home windows and doors, and utilize your air conditioner regularly to keep fresh air circulating throughout your home.
  • Water – Mold will breed very quickly if standing water is around. Be sure to remove any standing water from the outside of your home, or the bathroom areas. Keep moisture at a minimum.

How Can I Prevent It?

The best way to prevent black mold growth in your home is by keeping the moisture levels in your home at or below 50 percent. Installing a moisture meter in your home is a good idea to monitor all moisture in your home. Additionally, consider opening your windows and doors so that fresh air can blow through the home. Allowing a cross breeze can keep moisture levels down in your home and reduce mold problems.

Consequently, running your exhaust fans in the bathroom after a shower can reduce the amount of moisture levels. Keep the exhaust fan going for 20 minutes to successfully pull out all excess moisture. Finally, use thermal imaging devices to check the moisture levels in your walls. You might have a leaking pipe and thermal imaging can identify any increase in humidity and moisture levels in your walls.

Thermal imaging device for moisture detection.
Thermal imaging device for moisture detection.

How Much Does It Cost?

In most cases, mold removal will cost about $20 per square foot. Homeowners can expect to pay around $600 for small mold removal projects. However, larger projects for mold remediation can cost you up to $7,000. Also, if you have mold in your air ducts or attic space, you will likely pay between $3,000 and $7,000.

Now that you have an understanding of how fast black mold grows, you will want to read up on the safest ways to clean black mold from a shower. This is important to prevent health problems while you are working to remove the black mold.

Next, it is a good idea to continue studying mold. Knowing how to stop mold from growing in your home is vital to keeping your family safe and healthy. No homeowner wants to come into contact with black mold spores in their home.

Lastly, before even purchasing a home, you should have a mold inspection conducted during the home inspection. This is an important piece to purchasing a home. You need to know when to pull out of a home purchase when mold is present.

Conduct a mold inspection in your home.
Conduct a mold inspection in your home.

When Do I Call A Professional?

Dealing with mold is not something that homeowners want to get involved with. Black mold can damage your health and your home. When black mold arises, you will want to immediately call on a professional mold remediation company. Also, reach out to your local home inspection team so that they can check the entire home for mold. Additionally, they can recommend the most reputable mold remediation company in your local area.


To get your black mold issue under control, reach out to your local home inspection team. They will inspect your home for mold and determine how safe the home is. Consequently, it is vital that you immediately hire mold removal services to remove all black mold from your home. Reach out to Atkinson Inspection Services for a mold inspection and home inspection in Orlando, Clermont, and the Villages.