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Musty Odors

If you have noticed musty odors coming from your basement or crawl space, it could be due to a much bigger problem like mold growth and water damage.

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If you live in an older house, you may think that the musty smell is typical of the age of the structure. But that unwanted scent is more than a nuisance. A musty odor is one of the first signs of mold growth in your crawl space. And if left untreated, mold can do severe damage to your house’s foundation and your overall health. Along with mold, the odor can also be due to other issues such as high relative humidity. 

At Mount Valley Foundation Services, we know everything about how problematic mold growth can be. And we have a variety of solutions available that can help you remedy the issue and protect your home while ensuring your family’s health is safe as well. We are the oldest foundation service provider in South Carolina. Therefore, we have many years of experience repairing basements and crawl spaces, eliminating moisture, and ensuring all possibilities of future mold growth have been removed. If you could benefit from our assistance, contact our team today to schedule your free inspection. 

musty odor

What is the Cause of Musty Odors in Your Basement or Crawl Space? 

Three things must occur for that stale and unwanted smell to form in your basement or crawl space. 

Organic Materials 

That is the first thing that has to happen for the musty smell to generate. Organic materials can include various things such as the wood the floor joists are made from or insulation coming out of the walls or ceiling. While you can clean some of this organic material, it can be challenging to get to all of it, especially when dealing with a crawl space. And you can’t eliminate the wood from your foundation. Fortunately, organic material is only part of the problem. And if you eliminate the other parts, you can effectively eliminate the smell. 

High Relative Humidity 

That is the second part of the equation needed to get that musty smell. The relative humidity is the measurement of the amount of moisture in the air in proportion to how much water the air is capable of holding. Once the air reaches 100% humidity, it is completely saturated with moisture. That means if it goes over 100%, the excess moisture will need to go somewhere. Usually, it comes out as condensation on cool surfaces inside your basement or crawl space, such as organic materials. When that excessive high-level humidity meets the organic material, mold growth begins. 

Mold Growth 

Most of the musty scent you smell comes from the mold. A high humidity level of at least 60% is usually required for mold to begin to grow on organic materials. 

In most cases, the musty smell is due to mold growth. Mold will form anytime high relative humidity, or organic material is joined. However, even if your crawl space has low humidity levels in various spaces, mold can still thrive in the areas around water spots and where condensation has occurred. 

While mold is usually not toxic, it can cause respiratory issues and other health problems, especially for those with breathing issues. It can have a severe impact on your quality of life, even if you are an otherwise healthy individual. Many people experience increased sneezing, shortness of breath, or wheezing due to mold growth in their homes. And most of the time, they are unaware of the cause of their symptoms for a long time before the mold growth is discovered. 

Why Should I Be Concerned About Musty Odors? 

Musty odors are a critical sign that mold is already present in your home. And you should be concerned if you have mold growth. That’s because, along with being unsightly, mold can cause infections and trigger allergies in individuals who are allergic to mold. It can also be harmful to members of your household who have a compromised immune system. Not to mention, if mold is present, you could also have problems with moisture or water damage in your crawl space as well. 

What is the Cause of Water and Moisture Problems in Your Basement or Crawl Space? 

crawl space flood

Since musty odors are caused by mold growth and mold is caused by excessive moisture, if you eliminate the water from your crawl space or basement, you will prevent issues with mold and odors before they start. 

Here are a few of the causes of water buildup in crawl spaces and basements that all homeowners should know. By understanding more about the many different causes of water buildup, you can decide what solutions will work best to fix the problem. 

Leaks from Faulty Plumbing 

Plumbing leaks are one of the leading causes of water buildup in crawl spaces. Typically this is due to a sudden burst or frozen water pipe. There will often be a small leak that the homeowner is unaware of until the damage is already done. 

Wall Cracks 

Cracks in your foundation walls can be caused by settling soil or shrinkage. If the wall cracks are a result of shrinkage, it usually doesn’t require an immediate solution. But cracks that are there due to settling are a more severe issue. That’s because they will usually cause the underlying structure of the house to become weaker. That makes it possible for even more water and moisture to enter your home and open space for pests, insects, and vermin to enter. That type of infestation can wreak havoc on your organic material. 

Open Vents or Window Wells 

Vents and window wells were intended to allow natural light and airflow into the crawl space or the basement of your home. While a window can prevent water from entering inside, it can do the opposite if it is not maintained. It collects moisture from heavy rain then eventually releases it into the area it was designed to protect. 

Crawl space vents were added to older homes because it was believed that they would help improve airflow in the small and dark area underneath your home. Now we know that these vents are not. 

Faulty Drains 

If you have open floor drains in your home, and they are clogged, the water from your kitchen and bathroom sinks or your washing machine will not drain as it should. That leads to a flood in your basement or crawl space. 


When there is poor ventilation inside your crawl space, air filled with moisture will get stuck inside that space, and it will continue to collect moisture until the excess converts to water. That is known as condensation, and it is pretty standard in areas that do not have good air circulation. 

Cracks in the Floor 

Water that puddles below your home’s foundation will cause your basement floors to crack. When that happens, the water will begin to seep upward into the basement floor. That will happen with even the most minor crack so that the damage could go unnoticed for a while. 

Musty Odors


A basement or crawl space may require waterproofing for several reasons. However, the one major thing all of these reasons have in common is a fault with the ground contractors built the home from. 

There are hundreds of different soil types throughout the country and 180 different types recognized in South Carolina alone. But regardless of what type it is, the soil comprises three main ingredients, silt, sand, and clay. While clay soils that hold water are found across the country, sandy soils which are more draining are most common in the southern states. 

South Carolina is made up of sandy, clay, and silt soils, which makes it challenging to build on and is why there are so few basements in southern homes because of all the moisture. But for those homes in the area with basements, we offer our services for waterproofing to help prevent water damage. 

Here are a few additional causes of the musty basement and crawl space odors. 

Clay Bowl Effect 

Before building the foundation of your home, the contractors dug a large hole to accommodate it. Workers removed some of the soil to make the hole was then put back or backfilled to fill the gaps between the earth and the foundation walls. Instead of being densely packed in and secure, this backfilled soil is loose. That causes the soil surrounding the house to become saturated with water, creating what is known as a clay bowl. That puts pressure on the foundation walls that eventually cause cracks and leaks to occur. 

Hydrostatic Pressure 

That is the pressure caused by the Clay Bowl Effect. It causes a constant force on the walls by the soil and places the stability of the walls at significant risk. If it is not resolved in time, the walls will start to show signs of failure by cracking and bowing inward, allowing water to make its way inside. 

Settling Soil 

Settling soil is the result of the clay bowl effect and the pressure caused by it. Over time the backfilled soil will begin to settle around the house, and sometimes it will settle at a slope or angle. That makes it much easier for water to run next to your foundation and then contributes to even more problems. 


The weather in Greenville, SC can be unpredictable and receive lots of heavy rain from flash floods, hurricanes, and thunderstorms. This rain ends up on the ground around your home with nowhere else to go but into the soil and eventually into your home. 

Malfunctioning Footing Drains 

Footing drains are placed on homes while they are being built, This is to help re-route water, but many times they will become clogged and end up doing more harm than good. Instead of being redirected collects near the walls and adds to the pressure on the walls. 

Problematic Exterior Drainage 

Exterior drainage systems on a home can often cause problems. These issues, such as clogged gutters, allow water to spill out and go into the foundation. That will cause an issue with seepage. All above-ground gutter downspouts or conductor lines will allow water to drain close to the foundation walls, making it easier for water to get inside. Buried lines can also easily break or collapse and cause puddles or water backups. 

An Outdated Sump Pump 

Sump pumps play a crucial role in waterproofing basements and crawl spaces. And it’s essential to have a system that works well. If your sump pump is out of date or is malfunctioning, all your efforts in waterproofing your basement will be for nothing. Our technicians can help you find the best new sump pump model for your drainage needs. We can also service a broad range of sump pump models. 

One standard theory that you may find while searching for DIY solutions online is to use bleach to eliminate the musty smell in your basement. Bleach may be great at killing mold, but there are several things that you should take into consideration before you attempt to remove mold from your surfaces using it. If you only spray the moldy areas with bleach, you aren’t going to eliminate the problem. And if you don’t do it properly, you could end up causing severe health risks for you and your household. 

Although bleaching can be effective with the mold removal process, there is much more involved with removing mold and making sure it stays gone than simply spraying an area with bleach. It can be an overly complicated process that could be difficult for anyone inexperienced in this area. So, anytime you attempt to remove mold and eliminate it for good, we recommend that you do not use bleach and instead contact our professionals to provide you with a better solution. 

You can get in touch with our team by giving us a call today at 803-220-3550. Or you can visit our website and fill out our contact form to chat with a specialist. 

It can be challenging to pinpoint precisely how much it will cost to remove musty odors from your basement or crawl space. Different households have different needs, and the level of damage can range from mild to severe. That all impacts the total cost of the repairs. 

According to HomeAdvisor, the average cost of mold remediation in the U.S., which removes mold from your basement or crawl space, is between $50 and $3,000. The cost of these services goes up if technicians need to remove mold from behind finished walls or panels. And sealing the foundation to prevent future issues with moisture can cost homeowners between $2,250. And $7,100. 

At Mount Valley Foundation Services, we understand what a burden it can be to deal with mold growth or water damage. That is why we will do whatever we can to ensure our customers receive the best possible services at the best prices. Contact us today to set up a Free Inspection.  

How to Fix Musty Odors From My Crawl Space 

Now that you know what the cause of the musty smell in your basement or crawl space is, it is time to look at the best solutions for the problem. Repairing your basement or encapsulating crawl space to no longer have the stale, musty smell can be a difficult task. And if you are unsure about what you are doing, you could end up causing more harm than good by attempting to remedy the issue on your own. 

At Mount Valley Foundation Services, our technicians have the experience and training necessary to take care of your moisture problem and do the job right the first time, so you don’t endure additional repairs later on. We will provide you with various solutions for your problem and help you decide which one will work best for your situation and budget. 

Here are a few of the solutions that we offer to help eliminate musty odors in your basement or crawl space. 

Use a Dehumidifier 

A dehumidifier is a valuable tool that can be helpful with removing mold and mildew. These machines are designed to remove excess moisture from the air. But you should keep in mind that using a dehumidifier alone will not completely take care of the problem. Instead, it is best to use one paired with another solution offered by our team to remove mold and moisture altogether and keep it gone for good. 

If you need assistance purchasing a dehumidifier, our specialists will be happy to help you learn more about the different types and find one that will work best for your specific needs and your budget. Our technicians understand all there is to know about the various types of dehumidifiers on the market. We can also service a broken one or provide routine maintenance if needed. 

Remove Any Existing Debris Around the Home 

One part of the process is to go around and remove any excess debris that is lying around. It may seem harmless, but sticks, weeds, and other material can collect bacteria, contributing to mold and mildew growth. While the homeowner can pick up some of the sticks or trash lying around, one of our waterproofing technicians can provide you with more information on what is considered debris and how to remove all of it effectively. So before you decide to start on this process on your own, it would be best to get in touch with one of our experts first. 

Add a Vapor Barrier 

Once all the debris is cleared, our technicians will likely suggest adding a vapor barrier. Our vapor barriers are made from strong, thick, and durable material and prevent moisture from getting through. We guarantee that it will remain stable even with some light movement on top of it. 

Close all Open Vents in the Crawl Space 

While they are usually only found in crawl spaces, some basements also have open vents in place. These vents were once believed to help prevent problems with mold and moisture when in reality, they were contributing to the cause. Now that we know how crawl space vents do more harm than good, we suggest that our customers place crawl space vent covers over their vents to block out moisture effectively. 

Contact Mount Valley Foundation Services Today for a Free Inspection 

When you notice a musty smell in your home, you should act fast and contact our team at Mount Valley Foundation Services for immediate assistance. The sooner you take care of the issues causing mold and mildew to grow, the better off you will be. Our team will explain how we will effectively remove mold and moisture from your basement or crawl space and address any concerns you may have along the way. 

Mount Valley Foundation Services is the oldest foundation repair provider offering services to the residents of Greer, SC.  We have proudly served the residents of Charleston, Columbia, and Greenville since 1986 and always offer the highest quality service to our customers at the best possible price. We understand that no one wants to use our services, but they are necessary when your home’s structure is in danger of becoming damaged or destroyed. That is why we do whatever we can to offer our customers the fairest and reasonable prices for all our foundation repair and crawl space encapsulation services. 

Get in touch with our team today to learn more about how we can help you eliminate those unwanted and embarrassing musty odors from your home for good. Visit our website to chat live with a specialist or give us a call at 803-220-3550 to request a Free Inspection. We look forward to helping you keep your home safe, secure, and free from moisture damage for many years to come. 

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