Does Mold Die When It Dries Out?


This post may contain affiliate links. When you buy through some links on this post, we may earn an affiliate commission.

Mold has always been a confusing topic for most. It's not taught in schools or college unless you go into specific fields. It's a common substance in our environment and has a long history that's documented back to biblical times. That's right, mold was written about in ancient writing going back four thousand years in the Old Testament, specifically in the book of Leviticus. Curiously, it was called leprosy, although the translation would be better as “mold” and “mildew” when investigating the translation possibilities.

What Causes Mold To Grow?

You need two things for mold to grow. A food source is any organic substance. The other is moisture. These are the two main ingredients for mold to thrive.

People often state that warmth is also necessary, which raises a troubling question. How does snow mold exist if it takes warmth to reproduce and grow? There are likely hundreds of thousands of different types of mold; some do better in a warm climate, others can proliferate in extremely cold environments, and others fill the void in the middle of these two extremes.

What Happens To Mold When It Dries Out?

When mold loses moisture, it goes dormant. You could look at dormancy like a bear hibernating through winter to survive. It may dry out, stop reproducing mold spores and sit there waiting on moisture to start the growth process. To stop mold growth, you must remove the two main factors necessary for mold to grow. It's that simple. While other factors can speed up or slow down mold growth, such as warmth, or lack thereof, stick to the two main sources, and you'll be fine.

Is Dry Mold Safe?

That depends on the type of mold you're dealing with. Outside of foods that need mold, such as certain cheeses, mold should be considered dangerous to humans and animals, even if dry. Dry mold has dormant spores that can be inhaled into a moist lung. Now you have active mold.  Before mold can be cleaned off of walls, shower tiles, and other places within the home, it must be wet to remove it safely.

Otherwise, you potentially launch millions and millions of spores into the air. That's doing nothing but making matters worse. Small amounts of common household mold are usually removed with common cleaners such as mold and mildew remover for the bathroom and kitchen. According to the EPA, if the growth is over 10sq ft, you need to call a licensed and insured contractor that deals with mold. There are many reasons why they suggest professionals when you locate over 10sq ft. of mold in your home. Still, the main reason is if you can visually see over 10sq ft. of mold growth on surfaces like walls, floor, or ceiling, there's a high probability that you have even more mold that is hidden, likely in the walls, under flooding, or in the attic and its insulation.

Health Effects of Dry Mold

Disturbing a dry mold colony will dust the entire room and home with airborne mold spores that are now waiting to land on something with organic material and a source of moisture. It's what they do. It is so disturbing it is spreading the possibility of more explosive mold growth. This means you've put millions and millions of these spores in the air to inhale into your body. Not a good choice.

While there are only a handful of genuses of mold that are problematic for humans, they tend to love houses of all types and have throughout history.

Here are some other articles covering the potential negative health effects of mold in the home for humans and pets.

Mold Can Make You Sick – With Symptoms – Link
Is Penicillin Mold – Link
How Black Mold Affects Your Pets – Link
How To Treat Mold Exposure – Link
Mold Causes Serious Sinus Infections – Link

Let's not forget that mold has been developed and used as bio-weapons throughout history and likely continues to this day. If our own government used it as a bio-weapon, how can anyone call it safe?

How Long Can Mold Stay Dormant?

Dry Mold spores can remain dormant indefinitely, just waiting for food and water to appear. Once it has all the right conditions, it will start reproducing massive spores immediately.

What Humidity Level Causes Mold To Die?

While this question is impossible to assign a hard number to, there are general rules. Most experts suggest a humidity level below 50%, while some suggest it be as low as 30%. Even our company suggests somewhere in the 30 to 50% range; it's a bit more complex than what's stated to the average homeowner.

The goal is to prevent excessive moisture from condensing on surfaces within the home. Humidity levels can exceed 90% and not come to the point of condensation. Professionals are looking at humidity levels, dewpoint, and the current temperature in the home. Of course, the higher the humidity, the more condensation you can accumulate when the temp and dewpoint intersect. The higher the humidity, the more condensation you can expect when dewpoint and temps cross paths.

How To Dry Out Mold

You must dry the building materials made from organic substances (building materials in the home). But if the truth is told, you're not looking to dry the mold; you're looking to remove it by drying the area to prevent regrowth. It is why professionals remove the mold the best they can, preventing spores from being cast into the air.

They also close in the area and use negative pressure HEPA filtration systems to reduce the number of spores in the air while removing mold-laden materials such as drywall.

The affected areas are then encapsulated to keep mold from spreading and attaching to other building materials. PPE (Personal Protection Equipment) is also necessary during this process. Most of these encapsulators also have anti-fungal properties built into them to help kill and prevent additional mold growth.

How To Prevent Mold From Coming Back

Once infested areas are dried, any materials directly affected are cut out and removed, and the area is encapsulated, you should have a mold-free environment that prevents regrowth. Plumbing leaks and breaks are usually responsible for mold in homes and businesses. Your heating and AC unit already acts as a dehumidifier. Use them correctly, and you should be fine moving forward. If you live in the central Florida area, give Damage Control 911 a call if you have over 10 square ft of mold in your home. Your homeowners' insurance should cover the damages and repairs if it's from a plumbing leak.

Recent Posts