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Here’s Why Your Crawl Space Smells 

Environmental factors like standing, water, mold, and the stack effect all contribute to your smell crawl space. Learn how JES helps you fight back. 

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Smell something funny in your house, but you just can’t tell where it’s coming from? Did you know that your crawl space is the first stop for about 50% of the air you breathe in your home? So, if you’re smelling something funky with no detectable source in your home, the answer could be beneath your feet.  

Here, we’ll discover what could be causing that nasty smell, how it travels up to your living space, and how you can fight back against nasty smells.  

Where Do Bad Crawl Space Smells Come From? 

Standing Water

flooded crawl space

In the 1960s through the 1990s, home builders widely believed that crawl spaces should be installed with openings to allow a healthy airflow. Over time, it was discovered that crawl space vents were the source of crawl space related issues, as the openings allowed for humidity, water, pests, and other debris an entry point into the crawl space. If your crawl space has a vent or lacks any sort of protection,  water is likely to creep in and stagnate, creating a humid environment that attracts pests and perpetuates mold.  


wood rot

Since humidity and even standing water can find its way into your crawl space, mold will surely follow if the moisture is unchecked. Mold reproduction is airborne, meaning that it can easy spread and latch on to other areas in your crawl space, and that it gives off a particular smell. By the time you’re smelling the mold in your home, it will have progressed to a severe level. But even before it gave off a potent scent, the toxins in the mold may already be affecting your home’s inhabitants through allergies and asthma.  

Garbage & Stray Items

Whether it’s from you, home contractors, or previous owners of your home, trash located in your crawl space should be safely cleaned out. Just like any other unsavory problem sign lurking in your crawl space, trash can fester and stink over time. Not to mention, it can be just another area of your crawl space to acquire mold. 

Backed Up Sewage Lines

Sewer lines that run under your home are susceptible to clogging and backing up over time. If you have an old home, your pipes may be vulnerable to cracking, corrosion, and leakage. This type of crawl space contamination can be dangerous, so it’s best to call an emergency plumber as soon as you discover sewage leaks in your crawl space. 

Pests, Both Alive & Deceased

There are many different types of pests that can slither their way into your open crawl space. In Virginia, the most common and the most smelly are roaches, cave and camel crickets, snakes, rodents, and even raccoons. When these pests take root in your crawl space, you may be able to hear some of them; and you’ll definitely smell them. As the circle of life plays out, you may end up with the rotten remains of these pests causing a stink beneath your home. 

How Does the Air Travel into Your Living Space? 

So, you’ve figured out what might be causing the stench. But if your crawl space is separate from the rest of your home, how do the smells find your nose in the comfort of your living area? Here are the two basic ways that happens.  

Air Ducts

As you might already know, crawl spaces are primarily built for the purpose of concealing the “guts” of your home, like piping, ductwork, and various compact appliances. Namely it’s the location of your home’s air ducts. With a nasty crawl space that attracts pests and allows mold to thrive, these air ducts are at risk of acquiring damage. Termites or other hungry pests can chew holes in these air ducts, allowing an easy passageway for mold spores and scents from animal excrement to fill the rooms in your home. 

air ducts in wet crawl space

The Stack Effect 

You’ve heard the common saying that hot air rises—well that’s true, especially when it comes to your home. In houses, this phenomenon is called the Stack Effect. Its’ the idea that the air in your crawl space will eventually rise in through your home and out through your roof. With this air comes the toxins festering in your crawl space from all the sources we explained above.  That’s why crawl space health is so important. While it’s understandable to have an out-of-sight, out-of-mind approach to your crawl space, it can be detrimental to the structure of your home and most importantly, the health and safety of your family. A happy crawl space makes a happy home.  

How You Can Combat These Issues 

As a homeowner, you have a lot to manage. Add a nasty smell coming from down below and things can start to feel overwhelming. JES is here to help you with simple solutions that can prevent crawl space stenches from infecting your home again.  

  • Remove the Source of the Smell. Our team of experts will provide a free assessment of your crawl space to: identify the source of the stench; and recommend a pest control or mold remediation company that can clean up the area. However, only having the source of the smell removed won’t protect your crawl space in the long run. You’ll want to fortify your crawl space with solutions that can protect you for years to come.  
  • Dehumidifier. As we discussed, humidity and excess moisture is the main culprit of many crawl space issues. With regulated humidity levels in your crawl space, it becomes a less attractive place for pests and mold. Dehumidifiers also act as a form of purification, by filtering out the excess humidity. It can make a drastic difference on your family’s asthma or allergy symptoms.  
  • Crawl Space Vent Cover or Door. The crawl space door is the source of many crawl space issues, but we have a solution for that. A crawl space vent cover can completely seal off your home from the outside elements. By sealing off your crawl space, you can create a clean, cool, and dry space that supports you for years to come.   
  • Vapor Barrier. For added muscle, a crawl space vapor barrier helps not only regulate temperature, but prevents water from getting in. It also protects your appliances, like your dehumidifier and even sump pump from being flooded or being ruined by water. At JES, we only use the best materials. That’s why our vapor barriers are as thick as they come, at 20-mil at its thinnest portions.  

Find your service area

Northern Virginia

Northern Virginia

Cracks and water intrusion impact your home’s safety, health, and appearance. Repair and protect your home with trusted solutions only available from JES Foundation Repair.

Washington, DC

Washington, DC

Weather conditions in Washington DC can cause problems for your foundation and lead to structural damage around your home. JES has industry-leading solutions designed to repair this type of damage and keep your foundation protected from it in the future.

Charlottesville, VA

Charlottesville, VA

We understand that keeping your home protected is of the utmost importance, and Charlottesville’s rainy and humid environment can make that challenging. That’s why JES has world-class solutions and knowledge to keep your foundation permanently protected.

Fredericksburg VA

Fredericksburg VA

Fredericksburg’s location on the geographical boundary between Virginia’s western Piedmont Region and eastern Tidewater region create a challenging environment for your foundation. However, JES has industry-leading solutions designed to keep your foundation protected.

Hampton Roads, VA

Hampton Roads, VA

The Hampton Roads region is home to several cities in Virginia, including Norfolk, Chesapeake, and Virginia Beach. All these cities share similar weather and soil conditions, with sandy soils and an above-average amount of rain – a combination that causes damage to your foundation.

Northeast North Carolina

Northeast North Carolina

Northeast North Carolina’s heavy rain and unstable soils can lead to water, excess humidity, cracks, and unevenness around your property. JES has the best solutions to combat these problems and permanently repair and protect your home.

Lynchburg, VA

Lynchburg, VA

Muggy summers, above-average annual rainfall, and clay soils make Lynchburg a challenging place for your home's foundation. These environmental conditions quickly lead to crawl space, basement, or concrete damage on your property, and JES has world-class solutions to fix the problem

Roanoke, VA

Roanoke, VA

Situated in the Blue Ridge Mountains of Southwest Virginia, Roanoke has wet summers with weekly rain. When winter rolls around, the area gets plenty of snowfall too. All this moisture damages your foundation over time, but JES has world-class tools and experience to repair and prevent issues.

Danville, VA

Danville, VA

Danville’s native soil has a sublayer of clay that expands during frequent summer rains. This combination causes serious problems for your crawl space, concrete, or basement foundation. JES has world-class solutions to protect your property in any situation.

Richmond, VA

Richmond, VA

The sandy soil and wet climate of Richmond will wreak havoc on your home's concrete, foundation, basement, and crawl space. JES is here to help tackle the problems causing your foundation to falter!

Baltimore Metro

Baltimore Metro

Your home in Baltimore is plagued with foundation problems thanks to environmental problems like climate and soil type. JES Foundation Repair has the knowledge and high-quality products to repair them permanently.

JES Has What You Need for A Smell-Free Crawl Space 

We understand it can be stressful and even embarrassing to have smells permeating from your crawl space. You may hold off on inviting people to your house. And you may worry about the health of your spouse or children.  

At JES, we’re eager to provide a free inspection of your crawl space where we can find the true source of the smell, and work with you on a plan to make it better. We won’t pressure you into signing with us. We provide free, no-obligation quotes for our repairs so you can take time to figure out what’s right for you. It’s easy to start your crawl space journey with us. Get started by filling out this form or calling us today! 

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    Chester, VA 23831


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