7 Things You Don’t Know About Mold (But Probably Should)

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Mold is a jerk. Period. It grows fast, doesn’t need fancy accommodations, and absolutely wreaks havoc on anything it touches or gets near.

Mold doesn’t care if you are wealthy or living far below the poverty line. It doesn’t care if you are old, young, or somewhere in between. Mold doesn’t care where you were born, where you live, or who your family is.

Mold is very difficult to get rid of. It is the definition of an unwanted guest. As such, mold prevention is key to steering clear of the train wreck mold leaves in it’s wake.

I could write a novel about all the misinformation circling around about mold. There are a lot of things you don’t know about mold. Trust me. When I was going through my coursework to become a mold inspector there were a few things that made my jaw drop (like the fact that mold can grow on jet fuel! Say what?!)

Today I am sharing 7 things you don’t know about mold but probably should. These are things I see as important and also facts about mold that I feel most people don’t have a solid understanding of. The mold basics are also things I see misrepresented on websites and by remediation companies just trying to get your business.

So let’s get down to it shall we?

Water damage and mold around a light fixture in the ceiling

7 Things You Don’t Know About Mold But Probably Should

1. There are two types of mold. Viable mold and non-viable mold.

This isn’t to be confused with species of mold or categories of mold. Those are totally different parts of the mold story. Let’s take a look at what I am talking about.

Viable Mold

Molds are living organisms that require a food source and moisture to stay alive. Take away one or the other and mold can’t survive. As long as mold has a food source and a water source, it can live indefinitely and cause significant damage to anything it comes in contact with.

Viable mold is also known as:

  • Active mold / active mold growth
  • Live mold

Non-Viable Mold

When mold loses its food or water source it goes dormant. This means that is does not continue to grow and spread and cannot cause further damage to your property. The bad news is, as mold dies it dries out and starts to release spores into the air at a highly accelerated rate. Mold spores – dead or alive – have the same health effects on people and animals. In a lot of ways, non-viable mold is more dangerous than viable mold since it is often written off as “safe.”

Non-viable mold is also known as:

  • Dead mold
  • Inactive mold
  • Cremated mold (yes, apparently it’s a term)

2. There are no Federal guidelines specifying what constitutes an unsafe level of mold.

Yes, you read that right. As it stands now, unsafe levels of mold are completely undefined. This means that anyone, anywhere, in any profession can define how much mold is acceptable or unacceptable. In my professional and mold-experienced opinion, any level of indoor mold is unsafe and not acceptable.

A lack of Federal guidelines makes it very difficult for a tenant to hold a landlord responsible for mold related health issues. It allows insurance companies to deny mold related claims. It gives mold remediation companies the ability to create arbitrary guidelines for mold levels in clearance testing. It gives doctors an excuse to overlook mold as the root cause of health issues or to downplay the severity mold related illness.

This is why EVERYONE needs to educate themselves on all aspects of mold including mold testing, mold removal, and mold prevention.

3. If you see mold, you don’t need to spend money on tests to identify it.

Mold is mold. Sure, some species of mold are more dangerous than others and some species produce mycotoxins which can be deadly. But the bottom line is if you see mold you need to remove it. All mold must be removed and done so in the proper way regardless of the species. This brings us to #4.

4. 95% of the time you need to do more than just “clean” visible mold or remove mold off of something.

Cleaning or removing surface mold doesn’t always get rid of the mold problem. 95% of the time if you have visible mold on the surface of something, you also have mold that has rooted inside that same something. This means that you need to discard the moldy item (like a moldy end table) or replace the moldy building materials (like a moldy under-sink cabinet). Surface mold is the tip of a very dangerous iceberg.

In addition to that, if you have visible mold you most likely have air born mold spores floating around. So you need to “scrub the air” in your entire home using HEPA air purifiers. Your air ducts will need to be cleaned. Fogging with EC3 mold solution is also advised.

Remember – you need remove mold at the source AND fix the leak or eliminate the water source.

Any mold event larger than a 3X3 area should be handled by mold remediation professionals. I very rarely suggest that anyone try a DIY approach to remediating a medium to large scale mold problem.

Let’s talk about the 5% of the time when you can just clean mold off of something. What falls into that category?

Did the words plastic and metal grab your attention?

5. Mold can grow on ANYTHING.

That is not a typo. Mold can grow on absolutely anything like water and jet fuel which I mentioned above.

While mold grows most easily on porous, organic materials (like wood, wallpaper, and drywall), it can grow anywhere a spore lands. Plastic, metal, and glass are not immune to mold growth.

The reason mold can grow on non-porous surfaces is that it can survive on dust and debris that collect on those surfaces. A little dust + a little moisture = mold’s happy place even on your grandmother’s China dishes.

6. Over 50% of indoor mold is caused by issues with high humidity and lack of ventilation.

Sure, leaks and floods are responsible for a LOT of catastrophic mold growth. But high humidity and lack of ventilation in an indoor environment are responsible for most cases of room-specific mold growth. Think about your bathroom. Bathroom mold is so common. That’s because there is usually higher humidity, a consistent water source, and a lack of air flow or ventilation.

This is why it is important to monitor humidity throughout your house (check out my top picks for humidity meters) as well have use exhaust fans in the bathroom (this is my personal favorite), when cooking, and in the laundry room. Also open windows and use fans to move air around your home.

7. Mold doesn’t smell.

Bet that caught you off guard! Mold spores are odorless. It is the byproducts of mold (like mycotoxins) that create a scent.

This means that “mold” can smell like a lot of things. It can be a typical musty odor. It can also smell like cat urine. My moldy house smelled like burnt chorizo.

For a complete list of all the smells associated with mold, check out my post on What Does Mold Smell Like?

And there you have it! 7 Things You Don’t Know About Mold – but now you do!

What have you learned about mold that surprised you or caught you off guard? Please share as I always find it interesting to get other people’s experiences in the comments.

A moldy window sill with the words 7 Important Facts About Mold

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  1. Bryson Owens says:

    I like that you explained how active or viable mold is generally more dangerous. My wife and I are trying to make sure our basement is mold-free this weekend. We had a bad flood down there around a month ago and we are worried about the mold.

  2. Alice Carroll says:

    Wow, I never knew before that mold can grow even on liquid surfaces. I have an indoor fountain in the middle of the first floor of my house and I’ve always been worried that it might be contributing the to humidity of my home. Perhaps I should get a residential mold testing service to see if there is a possibility that my fountain could be susceptible to molds in the future.

  3. I lived in a house with mold for several months.My landlird refused to take care of it. I never knew how dangerous mold is. I’m still suffering from rashes, mood swings chronic fatigue and other syptoms. If a person even thinks they may have mold they should get out immediately!. It has completely ruined my health and life! Thanks for the information.

  4. Alice Carroll says:

    It’s interesting to know that there really is no material that has total immunity to mold growth. I’ve been thinking about having a having a home renovation soon in order to make my home mold-proof but I should probably think twice about that because of what you said in this article. I will probably just have to be vigilant and prepared to call in a home mold removal service at the first sign of mold growth.

  5. Zachary Tomlinson says:

    I find it concerning to learn that prolonged exposures to mold can give people health complications. My friend told me that he’s about to purchase a new home around the city. I’ll recommend that he contact a mold removal expert just to make sure that his new home is free of molds.

  6. Henry Cheston says:

    Wow. I am definitely going share this post about mold remediation with a few of my friends. Very cool information.

  7. Sherwin Locke says:

    Interesting stuff about mold remediation! I’ll probably share this with some of my friends. Thanks again for posting it.

  8. tacoma mold removal says:

    Many underestimate the danger of mold and also not realizing the reasons for their many ailments and poor general health. And the health of the entire family can be at stake. The best thing to do when we talk about mold, is getting a mold removal to avoid any big issues.

  9. Eli Richardson says:

    It really helped when you talked about how mold infestations are not only on your home’s surface. Recently, my wife and I came back from our vacation, and we realized how mold took hold of our home while we were gone. We think we have to get rid of it fast, so we’ll be sure to look for a professional’s help. Thanks for the advice on mold and how it invades your home’s insides.

  10. James Hoefer says:

    I saw no mention of using household bleach to get rid of mold – That is a remedy my family has used for decades (I’m 80 years old). Yes, it’s a nasty business, cleaning mold (like shower stalls, refrigerators, washing machines, etc) and one has to keep watch to make sure the mold is really gone and doesn’t come back – Granted, it’s a temporary solution, but as far as I have learned, there IS no PERMANENT solution (I’ve never liked the idea of hiring somebody to do for me what I can do myself. – not EVERY task required a trained professional.)

    What brought me to this site was a search for a way to keep bread from molding – the wife bought muffins – came in a clear plastic “clam shell” box – it’s very hot these last several days, and an unusual amount of rain – so the muffins “went bad” faster than usual. Rather annoying.

    What I was trying to find out was – – – Would putting a small ozone generator in the bread box prevent mold growth?

    if I put the device in the cold air return of the forced air heating system (nights get cold here, even in summer -we are at 4,500 feet elevation), I can smell the ozone after about an hour, so I know it is actually working.

    I set up the generator in the cold air return, then we vacate the house (go shopping) for several hours – it’s 35 miles to town, once a month – usually gone at least six hours), then turn off the ozone generator and air out the house when we return.

    I don’t know that it does much – if any – good, but at the very least it has a placebo effect – makes me THINK I’m getting rid of “nasty stuff” in our air. (I also have an air filter that incorporates a UV light in the air stream.)

    Anyone try the ozone in the breadbox idea?

    1. Hi James! I have an entire article on mold and bleach. Bleach actually is one of the worse things you can use. https://moldhelpforyou.com/bleach-kill-mold/ But you came here about bread mold. That is a tough one. Grains are highly contaminated with mold spores because of how they are stored. These get baked into breads and other baked goods and since breads have moisture in them, the mold spores flourish rather easily. Stick the bread in a plastic bag or container and you have a little humidifier going. The best solution is to store these types of items in the fridge. But I get that some people have an aversion to fridge breads and baked goods. The ozone in the breadbox won’t do much because the breadbox is not the issue. Now a teeny little dehumidifier might help. Something like this: https://www.amazon.com/Improved-Eva-dry-333-Renewable-Dehumidifier/dp/B000H0XFCS?&linkCode=ll1&tag=moldhelp-20&linkId=fe12a0fd748e38415e5588c138d24311&language=en_US&ref_=as_li_ss_tl I would give that a shot and see what happens!

  11. Excellent information -thank you for taking the time to educate us!

  12. Thank you so much for sharing! I live in a rental, and I’ve noticed mold growth in my bathroom. Since my lease is up in a few months, I don’t want to spend hundreds on professional mold removal. This information was really helpful.

  13. Thanks so much for sharing this info about mold! I have been suspicious of mold in my home & I think I am going to go ahead with a mold inspection. Wish me luck haha!

  14. Thanks so much for sharing this info about mold! I have been suspicious of mold in my home & I think I am going to go ahead with a mold inspection. Wish me luck haha!

  15. My son, lives in an old rental property and his shower is full of mold the shower, I. Put bleach on it, but I’m so worried about their 2 1/2 year old, and I’m sure the vents haven’t been cleaned in forever, he doesn’t want to hear it, but I have sleep apnea