Top 5 Types of Mold Found in Homes

Every homeowner knows mold in your home is bad news. It’s an eyesore, it gives off a terrible stench, and it can be hard to remove. But what exactly is that substance growing in your home, and how serious is it?

Knowing the different types of mold found in homes is important for several reasons. Once you familiarize yourself with the icky fungus then you can prevent or treat the issue should you ever need to.

What Is Mold?

Mold is the growth of minute fungi that grows on any particular surface.

Mold is a naturally occurring substance, but when it gets the perfect host, it can become a problem. The surface can be food, animal matter, or in this case, right in your home.

We’ve all seen mold on the food we’ve left in the pantry a little too long. But few people know what this fungus is and how it gets there in the first place.

Several different types of mold exist in the biosphere. They come in several odors and colors, and they have different health risks depending on the species.

Regardless of what type of mold it is, it is no place for a home. You should treat it as a health threat.

How Do You Avoid Mold in Your Home?

If there is a potential mold problem, you need to follow a few steps to eradicate it before it gets out of control. First, keep in mind that mold loves to grow in damp, warm areas.

In a home, several areas are prone to mold:

  • Bathrooms: Mold thrives in areas with high moisture and poor ventilation. Your bathroom is a prime home for fungus, especially if the room doesn’t have proper ventilation. Mold often grows in the corners and grooves around the shower or tub. The fungus can also be on the ceilings above showers. Keep an eye out for water buildup in these areas, and properly clean the bathroom and ventilate it to help prevent growth.
  • Underneath sinks: Beware of areas that are susceptible to water buildup. Periodically check underneath sinks for any leaks. Even drips can cause water buildup, which will eventually lead to mold growth.
  • Basement: The basement is probably the most common place for mold to grow in your home. Basements are the perfect breeding grounds for the gross fungi because they flourish in dark conditions. Humid, dark, and enclosed spaces are ideal for mold. The worst thing about having fungus in the basement is that if you ignore it, it can spread to the rest of your house. It can also develop into some more toxic types of molds if left untreated, like black mold. These types of issues usually require a licensed professional.

How to Get Rid of It

The truth is, mold can grow anywhere, so be on top of the cleaning and checking for any signs.

The best way to avoid any mold issues is to keep your home’s humidity levels at a reasonable rate. A standard level of humidity is between 40-50%. This percentage may fluctuate based on the climate where you live, and the winter months vs. summer months. If your home is always gross and damp, invest in a small dehumidifier to pull the moisture out of the air.

Another preventative measure is investing in an air purifier for mold, which kills the mold spores in the air and can prevent the further spread of mold in your home.

Even with a dehumidifier or an air purifier, you may still need professional help to get rid of the fungus. These devices, although powerful and helpful, do not eradicate mold. A professional can look at it and see what kind it is. Then the professionals can remove the problem from your house to ensure it doesn’t come back.

That being said, if you ever run into a mold problem, here are the 5 common types of mold found in homes. 

5.) Cladosporium

cladosporium mold in homes

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Cladosporium is one of the most common types of mold in homes.

Have you ever smelled a musty or old odor coming from the bathroom or your bedroom?

This type of mold is often responsible for that smell that won’t seem to go away. It won’t unless you do something about it.

Cladosporium is known as the asthmatic trigger mold. If you have asthma or respiratory issues, this is the type of fungus that could be detrimental to your health. Some of the most common symptoms of being exposed to Cladosporium spores are allergy symptoms and breathing problems. Prolonged exposure could lead to severe respiratory problems, especially in people with existing breathing issues.

Four types of Cladosporium can be in your home. All four of these molds will be terrible for your home’s indoor air quality:

  • Cladosporium herbarum
  • Cladosporium sphaerospermum
  • Cladosporium cladosporioides
  • Cladosporium macrocarpum

You can find this species in the warm and damp areas in your home like the carpet, wood, painted wood, mattress dust, and surrounding fans.

Properly cleaning and ventilating wet areas will help discourage Cladosporium growth.

4.) Alternaria

mold in bathroom

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Alternaria is another common type of mold that is both outdoors and indoors. Similar to Cladosporium, it’s well-known for being an allergy-causing fungus.

In the outside world, Alternaria spores exist in high quantities during the warm months. Windy and warm weather cause these spores to become airborne and circulate. Once inside, the spores can attach to the dark and damp surfaces in your home.

While there are over 40 variations of Alternaria, the two main types found outside are:

  • Alternaria alternata 
  • Alternaria tennuissima 

Alternaria’s presence is usually an indicator that you have a humidity issue in your home. In rooms with a lot of moisture like bathrooms, Alternaria spores will thrive. It is common to find this type of mold in damp areas like under the sink, near the showers, and in basements.

Some of the health risks that come from exposure to Alternaria are asthma attacks and allergy symptoms. Overall, this common mold is detrimental to your health.

3.) Aspergillus

mold on clothes

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Aspergillus is one of the molds that are indoors more than outdoors. It is so common that you may not even know it’s there. If you’ve ever dusted, vacuumed your carpet, or done other routine cleaning, you’ve likely come in contact with Aspergillus spores.

Aspergillus mold can be in old food, old leather, and cloth. Also, you may see it around the house in places like damp walls, carpets, and dusty furniture.

Because this species is so commonly found in the homes, some believe it isn’t as big of a health risk as some of the other molds on this list. Some scientists say it only causes minor health risks, like mild allergy symptoms or nothing at all. However, like any mold, prolonged exposure will affect someone with health issues.

There are also specific types of Aspergillus that are more toxic than others:

  • Aspergillus clavatus
  • Aspergillus flavas
  • Aspergillus fumigatus

These particular species are considered to be extremely toxic and could cause severe health issues.

If you’re not a microbiologist, the only way to tell the difference between all of these is to get help from a professional. Our advice is like with any other mold on this list: get a professional’s help.

2.) Penicillium

types of mold penicillium

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Mold often occurs in homes that have suffered water damage. Once carpets and wooden floors get the slightest contact of the mold spores, it spreads rapidly.

Penicillium is one of those types of molds that cause worry. This mold is aggressive, and when inhaled, it can cause tons of health problems as well.

Let’s break it down. If you think the name Penicillium sounds familiar, that’s because it is. This mold is the substance that made the world’s first antibiotic, penicillin. If you’ve ever had a bacterial infection, you can thank penicillin for getting rid of it for you.

In spite of its medical uses, penicillium mold in the home is not beneficial. This mold often grows on fruits and vegetables. Penicillium can be on spoiled apples, oranges, and other types of plants that you have in the kitchen.

When it comes to the types of Penicillium, there are over 200 species on earth. The most common are:

  • Penicillium italicum
  • P.  digitatum
  • P. expansum
  • Penicillium chrysogenum

P. chrysogenum thrives in damp and humid environments, like bathrooms and basements in a home. Mold-sensitive people will suffer from allergy symptoms and respiratory issues when they come in contact with it.

So, even though there are species of this mold that have given us powerful antibiotics, other species are still something to worry about if you have it in your home.

1.) Stachybotrys

types of mold black fungus

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Last but certainly the worst is Stachybotrys. This type is what most people know as black mold, and it’s in many homes. The thing that makes this difficult to see is that there are tons of other mold species that appear black, but aren’t Stachybotrys. You will, however, recognize the stinky, musty smell.

Nonetheless, if you find black mold and professionally get it identified as Stachybotrys, then you have a severe problem. Another marker for this mold is toxic mold because of the mycotoxins it creates. Anyone who breathes in black mold spores is at risk of developing severe health problems.

Stachybotrys got its bad reputation back in the 90s. It is one of the most feared molds found in homes because many believe it caused several infant deaths in the 90s. Scientists linked the lung bleeding in infants to the outbreak of Stachybotrys in homes.

Generally, the places to watch out for this nasty mold is near air conditioner pipes and other damp and cold spaces. It would be terrible to leave this issue untreated and develop breathing issues, sinus complications, and even lung inflammation.

So now what?

If you fear that your home has mold, act quickly. You may be able to stop the problem for worsening if you get on it before it spreads. Either way, the breakdown of the five types of mold can help you better understand how these organisms work. When you understand it, you can further prevent it.

Read our next article to learn more about how a dehumidifier can help with mold.

Top 5 Types of Mold Found in Homes

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