Signs You May Have Mold Inside Walls And How To Deal With It

Signs You May Have Mold Inside Walls And How To Deal With It

Do you know that mold has existed for several million years now? As a natural phenomenon that occurs nearly anywhere there is oxygen and moisture, it is no surprise to discover mold around your home or office inside walls.

So, how can you tell the signs of mold in walls? And do you know how to remove mold from inside walls? Read on to discover that and much more!

Signs You May Have Mold Inside Walls And How To Deal With It

What Causes Mold in Walls?

Mold will quickly grow inside your home's walls when the surroundings encourage survival. While various things cause mold to grow in walls, water leaks, high humidity, and massive condensation top the list. Here's more about that.

Water leaks

Mold will grow inside your walls if water leaks into the walls' interior spaces. For instance, leaks from your plumbing system will increase the moisture level and dampness inside your walls, promoting mold development and proliferation.

Flooding and swamping

Premises that have been plagued with floods are a breeding site for mold. After the downpour, it might take several days or weeks for your home to dry completely. Meanwhile, your walls absorb lots of water, and the dampness gives mold a perfect space to thrive.

Ventilation issues

Poor ventilation in your space allows the moisture and humidity to gather in your home's walls and basement. Also, poor ventilation means that the condensation rate is high inside walls. Since mold only needs 24 to 48 hours to start growing, these conditions will have it spread quickly.

High humidity in the air

High moisture levels in the air (humidity) will cause the air to feel damp. Humidity levels between 55% and 60% accumulate a lot of moist and stagnant air, easily leaking into the walls, promoting the growth of hidden mold inside walls. This is quite common during the summer months.

Health Dangers of Mold inside Walls

Is mold inside walls dangerous? Yes, mold inside walls is detrimental to your well-being and results in health problems when not remediated on time. Mold spores trigger uncomfortable symptoms like skin rash, eye redness, runny nose, and sneezing. These symptoms can get worse among people with certain medical conditions like sinusitis.

Mold is also linked with allergies because of its toxic and irritating allergens (spores). With growing levels of black mold inside walls, you and your loved ones have a high risk of developing mold-induced infections like asthma, fungal poisoning, and hypersensitivity pneumonitis.

Mold in Walls & Mold on Walls - What's the Difference?

The primary difference between mold on walls and inside walls is the position and visibility. You can easily see the signs of mold on walls, like black spots and stains. Detecting mold inside walls is confusing to many, but the reality is if you notice mold signs on your walls, it indicates a bigger mold problem on the inside of exterior walls.

What are the Symptoms of Mold in Walls?

How do you tell if mold is inside walls? Whenever you suspect mold in walls, the mold symptoms will reveal whether it's mold or something else. But before that, physically assess your internal space for mold and detect what might be bringing out the mold issue.

Testing For Mold inside Walls

You can confirm the presence of mold inside your walls through a physical and internal inspection. Check for water damage or visible signs of mold growth.

Also, inspect the inside of the walls, like the attic and insulation, for signs of mold growth. Smelling your electrical outlets like air conditioners for mustiness will also indicate if there's mold inside that might have spread to the walls. Temperature and humidity measuring devices will erase any doubts.

Discovering Mold inside Your Walls

How to detect mold inside the walls of your house can be challenging because mold is not always visible. It's even more complicated if the mold has not developed enough to display signs on the walls.

Check for mold if any of the following have occurred:

  • Moisture in your home's foundation from poor construction or flooding.
  • Leaking in the roof, causing water infiltration inside the walls
  • Leaks in your pipes, exposing your home's internal structures like walls to moisture.
  • Poor ventilation, resulting in dampness, high humidity and increased condensation.

Signs of Mold Growth

It may take time for you to notice leakages in roof and pipes, giving the mold enough time to grow. You can tell the signs of spreading mold inside walls through the following:

  1. Musty odor: Expect a musty smell whenever you have mold inside walls; it smells like old water-infested wood. The smell is usually restricted to a specific area and does not disappear until you get rid of the mold.
  2. Wall discoloration: Check for weird colors on the walls. Mold causes black, yellow-green, or brown spots on walls. In addition to the discoloration, your walls might have developed cracks, peels, or bubbles.
  3. Water stains: Water stains on your wall may also indicate the presence of mold. It shows excess moisture in the walls, which promotes rapid mold development.
  4. Base molding: Can you see white or thread-like clusters around the base of your walls? This is an indication of base molding. The mold will appear in various colors, like black and gray-green.

How to Treat Mold in Walls

Mold inside your walls will stress you, but it is not impossible to get rid of. There are two ways to remove mold from inside walls; doing it yourself or engaging an expert.

DIY Mold Removal and Treatment

This is where you remove the moldy drywall, assess the situation, clean and treat the mold, encapsulate it, and rebuild the wall. However, DIY mold treatment is risky; you run a real risk of spreading the mold and compromising your health due to the mold spores and the toxic chemical treatments.

More so, it's easy to damage your home during removal and incur an extensive loss. Experts only recommend DIY if you are certified, experienced, and own the right tools for mold remediation.

Professional Mold Removal Services, Like FDP

Hiring professional assistance is the most recommended option for killing mold inside walls. At FDP Mold Remediation, we will help you remove mold hidden inside your walls with a guarantee of the best results. Here's our proven professional approach.

Step 1: Moisture source removal

Moisture and oxygen are food for mold; they help it grow and thrive. Removing mold inside your walls without handling the moisture would not solve the problem. The water problem should be repaired to guarantee a good result. Our teams handle this in some areas, but not in all.

Step 2: Cleaning and treating the mold

The next step is cleaning the infected area, especially on the nonporous materials. We use eco-friendly detergents and the HEPA filtering technique to clean and clear the air of airborne mold spores. For the porous materials, our professionals use friendly antimicrobial treatments to kill the remaining mold.

Step 3: Removing and replacing the affected material

Finally, we remove the materials most affected by the mold, whether it's the insulation or drywall, so that you can have them replaced with new ones. You can choose to replace the drywall with mold-resistant alternatives to provide a long-term solution to the problem. A licensed contractor will help you with material sourcing and reconstruction.

How to Prevent Mold in Walls

Are you worried that the mold infestation will develop again? With the proper preventive measures, you will comfortably prevent recurrent mold infections inside your walls.

Emphasize the following:

Regular wall inspections

You will often not notice when mold starts growing inside your walls. For instance, pipe leaks and moisture problems inside the walls are hardly noticed until they develop into severe problems. Regular mold inspection is recommended to spot the issue and its symptoms on time before mold spreads everywhere.

Frequent cleaning

Cleaning your spaces around the wall or the exterior walls will help prevent mold inside walls. Make sure you use the right household detergents, then rinse and leave the walls to dry completely. Knowing how to clean mold inside walls also lessens moisture buildup. You will also spot issues early if you clean and inspect your walls periodically.

Humidity control

Controlling the humidity in your house with a dehumidifier, exhaust fans, or ceiling fans helps. Humidity control helps prevent moisture development inside your walls.

Room ventilation

Proper ventilation will prevent moisture accumulation within your space, especially the internal structures. Pay attention to areas like your bathroom, bedrooms, and kitchen because this is where humidity and moisture levels are high.


Mold inside walls will make your home unsafe and uncomfortable to live in. Ready for professional mold remediation services? Whether in your residential or commercial space, we will restore your space and keep every room occupant safe with our professional mold removal services. We also provide solutions to help you prevent mold infestations in the future.

In addition, we offer professional mold inspection, mold testing, and a complete mold remediation package. It sounds like a good deal, right? Call us today at 877-421-2614 for a fast estimate and consultation on how to get rid of mold inside walls.


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Jacob Smith

About Author

Jacob Smith is a mold remediation expert at . He has over twenty years of experience in the field and likes to write about mold when he is not remediating this fungus from someone's home or facility.

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