What Does House Mold Smell Like? A Comprehensive Guide

The answer to “what does house mold smell like” is that it smells musty, damp, and sometimes like rotten wood. You get the explanation for these scents below. 


what does house mold smell like

Start Of Mold Formation

When mold is just beginning to grow on your surfaces, the smell will not be as pungent. Due to this lack of identifiable smell, the fungus may grow undetected in your house and rapidly spread.

Mold mainly grows after water damage. They start to form as early as 24 hours after leaks happen.

In those early hours, you will not notice the mold smell. However, once 24 hours have passed, and mold has formed, you may note a “musty” odor.


The “Musty” Smell Of Mold Explained

The first response of homeowners upon encountering a musty smell is to open the windows. Opening the windows leads to more air circulation, which keeps the said smell away. 

However, encouraging airflow is not enough to remove the musty scent. It is not helpful because the root cause of the odor is not fixed.

Once you close your windows, the smell will fill the room again. If you repeatedly encourage air circulation without addressing the mold problem, the odor will worsen and become more pungent.


Where Is The Damp Smell Coming From?

The damp smell of mold is due to moisture. Mold grows due to certain conditions, and one of the criteria is moisture.

Also, as mentioned above, mold typically grows after water damage. The best way to prevent mold growth is to stop water damage from happening. 

Here is an article outlining how to fix a water damaged plaster ceiling to guide you in the repair process of water damage. Not to mention, leaks from above (e.g. roof or ceiling) often lead to rapid mold growth in a room.

First, they affect the ceiling itself, then they affect the walls. Later on, the water damage reaches the flooring. 

It is vital to prevent water damage from happening. Check your plumbing systems and your roof to prevent leaks.

Generally, you smell the damp odor when you are in the basement or the bathroom. This leads you to dismiss the scent as just due to the abundance of water.

The “abundance of water” reason is partially valid. However, it is primarily due to the development of mold in high moisture and dark environments.

This damp smell should not be dismissed and should alarm you that your home has a mold problem. 


Rotting Wood Smell Of Mold

Mold spores are airborne, which means they are everywhere. Be it indoors or outdoors, the air holds mold spores.

It is not surprising to smell a scent characteristically like mold outside. For example, when you’re hiking, and you chance upon a musty odor.

Most of the time, outdoor mold smells like rotting wood. It’s typical for outdoor spaces to have mold because it helps break down organic materials for the environment.

However, if you notice a rotting wood smell indoors, then you should investigate where it’s coming from. Rotten wood smell means that your wooden beams may be damaged.

Fungus, like mold, loves moisture on organic material (wood). It is not far-fetched that they grow and feed on it until it is weakened.

To know more about rotting wood, here is an article about how long before wood gets damaged from water.

Moreover, the prolonged moisture on wood due to mold may invite termites. The presence of termites is a cause of concern because they will really run down your home’s structure.


What To Do After Smelling Mold In Your Home

First, identify where the mold is coming from. Check the basement and other water-damaged prone areas.

After that, assess the extent of the mold contamination and water damage. If it is beyond your level of expertise, then contact a professional instead.

If the mold damage is within your level of expertise, then start by clearing out the place. You must separate the mold-contaminated items from unaffected ones.

Discard the objects that cannot be salvaged and were thoroughly affected by mold. Be sure to place them inside a tight plastic bag, so the mold spores do not spread to other surfaces.

Then, start cleaning off the mold from the surface. There are several cleaning solutions you can use to clean mold.

There are household cleaning solutions that can kill and prevent mold growth, like vinegar, bleach, and hydrogen peroxide. When you use them, make sure you wear protective equipment like gloves and goggles to prevent your eyes or skin from possible damage.

Also, be careful of mold exposure since it can bring about skin allergies. For some, it can trigger an asthma attack and may result in severe respiratory issues.

Ensure children are not playing around the area where there is mold or water damage because they are susceptible to mold exposure.

Lastly, after fixing the mold and water damage, ensure that the area is well-protected. Install mold prevention measures (e.g. humidifier), if necessary. 



Knowing what does house mold smell like is helpful in mold identification. It serves as an alarm to alert you of possible mold problems in your home.

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