Different types of molds (and how dangerous they are)

by Mary Evans

If you’re here, you’ve probably found something strange growing at home and you’re thinking it might be mold. Well, you’re in the right place!

First things first, don’t panic! But don’t let it stay there either. You’re on the right path. It is impossible to prevent mold from appearing at all. Yeah, you can try by reducing the causes but it’s not your fault if they keep coming back.

Now, we are going to see a little more in depth each type of mold but there’s one thing they have all in common (and that’s for sure!)… They loooove humid places. A place with moisture is a place with mold (or at least with a high probability of having it!).

12 Most Common types of Mold

As you already know, we are going to take a look at the 12 most common types of mold that can appear in any home.

To make it easier, I’ve separated them in 3 levels based on how dangerous they can be to our health: low, moderate and high. Very simple.

Danger level: Low

1. Alternaria

Mold Alternaria

This one’s the most common of all allergenic molds. They love damp places. It spreads rapidly so beware! If do nothing, suddenly you’ll see yourself surrounded by lots of it!

Type: Allergenic

Color: Brown and dark green

Look: Velvet or “little hair”

They love: They appear wherever there is a water damage such as bathtubs, sinks and showers.

Risks: Asthma, allergic reactions such as watery and itchy eyes, cough…

2. Aureobasidium

Mold Aureobasidium

Be careful not to touch it with you bare skin as it could potentially cause you dermatitis. It isn’t to dangerous but it’s important to have it removed as it could also break into the air.

Type: Allergenic

Color: Pink, black and brown

Look: Moist paint

They love: They love to hide behind wallpaper and painted or wooden surfaces.

Risks: Skin, nail and eye infections.

3. Trichoderma

Mold Trichoderma

They love to be where condensation is, so you may find them in your HVAC conducts and A/C filters also. They grow rapidly and form colonies.

We’ve considered that it’s not dangerous normally but it could cause great damage as it destroys almost everything they grow on, such as wood, paper or textiles. They could harm badly the structures of your house if you catch it too late.

Type: Allergenic

Color: Green and white

Look: It looks like wool

They love: You can find it in wet or moist carpets, fabrics, wallpaper, etc.

Risks: "Most trichoderma molds are non-pathogenic," AerIndustries states, but other types produce mycotoxins, which can cause sinusitis, allergic reactions, and other health problems

Danger level: Moderate

4. Aspergillus

Mold Aspergillus

This is the most common mold found in all US homes.

Type: Allergenic, but could be toxic

Color: They can have many different colors

Look: The look like spores and form big layers on the walls

Risks: It could lead to allergic reactions and respiratory infections. And some of these species may produce aflatoxins, which is a deadly carcinogen.

5. Chaetomium

Mold Chaetomium

It’ll be easy for you to detect as it usually starts spreading a musty smell. And it grows chronically in moist conditions, so be aware to remove them completely if you want to stop them from appearing again.

Type: It could potentially be toxic

Color: Start being white but with time changes to grey, brown and finally black.

Look: It looks similar to cotton.

They love: You can find it in water-damaged homes (especially in leaking roofs, pipes, damp basements, etc.)

Risks: Nail and skin infections. In some cases it can be dangerous to people who have compromised immune systems.

6. Cladosporium

Mold Cladosporium

This guy doesn’t care about the weather. It will appear on cold and warm conditions. But one thing’s for sure… they love ot hide inside cupboards or under floorboards.

It shouldn’t be ouched directly as it could cause skin and lung irritation.

Type: Allergenic

Color: Green and brown

Look: Very similar to suede

They love: You’ll find it in carpets, upholsteries, fabrics, etc.

Risks: It can cause respiratory problems and allergic reaction in eyes, skin, throat and nose.

7. Mucor

Mold Mucor

This one grows quickly. And it might seem harmless but don’t think about touching it!

If you think you have mucor at home call an expert inmediately to have it removed.

Type: Allergenic

Color: Grey and white

Look: It looks just like spores

They love: Moisture and condensation is their dream-land, so anywhere near an A/C unit, HVAC conduct or a damp carpet that’s where you’ll find it.

Risks: It can start with asthma symptoms but you could end up with a fungal infection in your eyes, lungs, brain, nose and sinuses.

8. Penicillium

Mold Penicillium

You may be wondering…. is it the same as penicillin? Well, yes and no. This is what it is used to create it.

Type: Allergenic

Color: Blue and green

Look: It has a velvet texture

They love: Damp and moist places such as carpets, mattresses, wallpaper, etc.

Risks: The spores can easily spread thoughout the air in your home. And this can cause respiratory problems, such as asthma, pulmonary inflammation and potentially chronic sinusitis.

Danger level: High

If you have this at home, keep everyone away as it is extremely harmful and have it removed inmediately by professionals.

9. Acremonium

Mold Acremonium

If you have this at home, keep everyone away as it is extremely harmful and have it removed inmediately by professionals.

Type: Toxic

Color: Pink, orange, grey and white

Look: It looks like a powder but starts as a moist substance.

They love: Home systems like humidifiers, drain pans or windows are their favourite place to be. It can also grow right next to other types of mold we haven’t seen yet such as, strachybotrys (black mold) and others.

Risks: It is very is dangerous. It can cause immune system diseases, impaired brain function and bone marrow diseases. It can also create dangerous problems in homes.

10. Fusarium

Mold Fusarium

Did you know they naturally grow on food? Well, you don’t want them in yours!

Type: Allergenic and Toxic

Color: Pink, red and white

Look: It’s just like cotton candy

They love: They live in carpets, wallpapers, etc.

Risks: They go from skin infections to bone a and lung infections, brain abscess and allergic reactions such as runny nose, sore throat, itchy eyes, sneezing, etc. An in the end, it could also damage your nervous systems, leading to potential hemorrhage and internal bleeding.

11. Stachybotrys (AKA Black Mold)

Mold Stachybotrys

This type of mold can cause neurological and pulmonary problems in your kids. So beware! If you think you might be growing black mold at home, call a remediation professional asap to have it removed.

Type: Toxic

Color: Dark green or black

Look: It has a slimy texture

They love: If you have a place at home that has been wet or humid for days, then watch out fot this “bad boy”.

Risks: They can provoke severe health troubles (i.e. fatigue, breathing problems, sinusitis, and depression). It is also known to have caused neurological problems and pulmonary bleeding, especially in kids.

12. Ulocladium

Mold Ulocladium

And last but not least! This type of mold could be easily confused with others which aren’t that dangerous.

If you have it at home, then you probably have a water damage somewhere.

Type: Could be allergenic and toxic

Color: Black

Look: Black in color, typically

They love: You can find it in high condesations places such as bathrooms, basements, kitchens and windows.

Risks: You could suffer from high fever, asthma symptoms and skin infections.

A great solution: Air purifiers

Now that we’ve covered all the types of mold that could appear at your house, let’s talk about prevention.

If your house suffers from high temperatures and high humidity then mold will find it’s way in. For them, that’s paradise! And since we’ve seen how dangerous they can be, it’s time to take action.

First, if there’s mold in your home, call a professional inmediately. This way it won’t be able to spread much more. Once they’ve solved the problem, to avoid having this enemies back in, we recommend you to buy an Air Purifier.

Air Purifiers work the following way: they trap the mold spores floating in the air of your home before they land and spread all over your carpets and walls.

If you’re going to buy it make sure it includes a HEPA (high-efficiency particulate air) filter.

Here you have some options:


And… that’s a wrap!

I know how worrying it can be to have something strange-looking crawling up your beautiful walls and carpets… trut me, I know! But once decipher what’s that thing you have, you can tackle the problem the right way.

If you have mold on the a carpet at home, don’t worry. We’ve got you covered with this article were you’ll find all the information you need to save your carpet from getting all ruined.

Mary Evans Picture

By Mary Evans

Vacuums, Steam Cleaners, Robot Cleaners, etc.

My name is Mary and I'm a mother of 3! I worked for a big company for 10 years until I decided to stay at home to take care of my family. Every since cleaning has become sort of my hobby and profession at the same time. I write about vacuum cleaners, steam cleaners, etc. I just find it a lot of fun!

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Mary Evans Picture

Mary Evans

My name is Mary and I'm a mother of 3! I worked for a big company for 10 years until I decided to stay at home to take care of my family. Every since cleaning has become sort of my hobby and profession at the same time. I write about vacuum cleaners, steam cleaners, etc. I just find it a lot of fun!

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