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High Humidity

Humidity buildup can prove damaging for your crawl space and home as a whole. How can high humidity levels cause issues within your home’s crawl space?

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Your crawl space is perhaps the most important space in your home. It contains plenty of essential systems that keep your home running, and serves to elevate your house up from the soil below. Too often this space is neglected due to many homeowners’ own lack of experience with this space. In fact, many homeowners will not even know they have a crawl space, much less where it is or how to protect it.

This can be especially hazardous if you allow too much humidity or moisture to build up in this space. Moisture alone can create plenty of damage to the important systems within, inducing rot, wear, or general destruction of your property.

A loose crawl space door or damage within the crawl space itself can leave your home susceptible to high humidity levels. The more humid this already small space becomes, the more water damage your home is likely to face.

Let’s take a closer look into the most common problem signs you can keep an eye out for, how humidity can cause crawl space damage, and how you can prevent humidity levels from rising around your home below.

How Easily Can Humidity Build Up in the Crawl Space?

Humidity is basically moisture that floats about in the air. All homes have humidity within them whether you can feel this moisture or not. A healthy level of humidity should not cause your home any problems whatsoever. It is only when these levels rise will water damage start to occur.  

High humidity levels can cause all sorts of issues. Leaks or floods can be traced back to high humidity levels condensing into liquid. Mold and mildew spores and pests alike are more likely to root themselves in moisture-ridden homes.  

It does not help that North Carolina’s climate tends to be rather humid in the summer. Indeed, any fiberglass insulation installed within the crawl space coupled with all that outside humidity rushing into the crawl space only allows for easier moisture buildup in this space. You might be facing preventable issues every summer. Calling the crawl space experts to seal off your crawl space from this outside humidity can be a great first step to protecting your home from any moisture problems.  

It is surprisingly easy for humidity to build up within the crawl space. Let’s take a closer look into how this phenomenon occurs below.  

reading moisture in crawl space

Relative Humidity 

First, it may help to understand how humidity tends to build up over time. The relative humidity of any given area is measured by the amount of moisture floating about the air in relation to the temperature. Therefore, the hotter it is, the more moisture the air can hold. This only allows humidity to more easily build up and exceed healthy relative humidity levels.  

A healthy relative humidity level for a house should not exceed 50 percent capacity. Even 60 percent capacity is pushing it, as those conditions can allow mold and mildew spores to thrive and grow. Should the moisture levels in the air exceed 100 percent capacity, however, the humidity will then start to condense into liquid drops. These drops can easily flood your crawl space. This can be especially dangerous in the crawl space due to all the crucial components stored within it.  

High humidity levels can also cause the wooden floor support beams to rot away. This can then leave your floor to sag or bounce in places.  

How Can Humidity Stack Up? 

Humidity buildup is rather common in regions that already have plenty of humidity. Homes in North Carolina will often face humidity issues during the summer, which allows this buildup to occur more easily. The crawl space is a very tight area with very little ventilation of its own. Coupled with the fact that insulation creates an already warm atmosphere, and this makes it the perfect environment for humidity to expand even further.  

Humidity can also evaporate from any water that pours into the crawl space. This means that days after a storm, you could find your crawl space flooded with both liquid drops and overbearing humidity. Hiring a crawl space expert to install solutions that can protect against both floods and humidity is key to keeping your crawl space totally dry.  

What Can Cause High Humidity Levels?

You might think a little water might be harmless, but this is not the case at all. Any water vapor in the air that finds its way inside the crawl space will ultimately ruin most, if not all the important systems stored within it.  

High humidity levels can be entirely preventable if you understand what causes them to build up in the first place. Taking steps to protect your home against this damage can help prevent the very worst of it from negatively impacting your home. Below are some of the most common causes of high humidity buildup.  


It makes sense that more humid climates would suffer more from high humidity issues. Raleigh and Winston-Salem both seem to accumulate a steady stream of humidity throughout the year, largely due to North Carolina’s overall proximity to the Atlantic Ocean. Both cities face an average of around 70 percent or more relative humidity levels year-round, which can obviously cause issues.  

All homes need to be at around 30 to 50 percent relative humidity at all times to stay healthy. If this percentage reaches much higher than that, then you will start to face mold and mildew issues, pest infestations, and overall muggy air inside your own home.  

The Stack Effect 

In the summer, hot, humid air from outside will waft into your open crawl space. Because your crawl space also contains your HVAC system, this hot air will then spread throughout the rest of your home. The hot air may also rise from the crawl space to affect your home that way as well. As a result, both your air conditioner’s cooling settings and summer energy bills will skyrocket.  

Similarly, in winter, cold air can push out any warm air within your home. This is because hot air is much lighter than cold air. In turn, you may try to turn your heater up even higher just to stay warm.  

This is what is known as the stack effect, and it can contribute to much higher energy bills overall. The average homeowner will try to save money where they can. By calling a crawl space expert to implement a solution that counteracts this effect, you will end up saving a lot more money for yourself in the long run.

Common High Humidity Problem Signs

Homeowners will have limited options for addressing humidity damage on their own. Rather, it is much more helpful to watch for any smaller problem signs to mitigate this damage before it grows worse.  


If the crawl space is damaged in any way, that damage can easily spread over to the foundation as well. You might start to notice cracks appearing on the concrete around your home, too. Cracks can also let in more humidity to cause even more issues within the crawl space.  

Cracks need to be treated as soon as possible, or you could risk the existing damage growing worse. The crawl space experts at Tar Heel Basement Systems can offer your home free crawl space inspections. We can assess the extent of the damage in your crawl space and offer powerful solutions that will permanently prevent any new cracks from forming in your crawl space ever again.  

moldy crawl space

Mold or Mildew   

Mold and mildew are common fungi that grow within damp areas. High humidity in the crawl space creates just the right conditions for the spores of these fungi to take root and grow at a rapid pace. Even a single spot of these fungi can hold millions of spores. Mold and mildew growth can be especially dangerous within the crawl space, as it contains your HVAC system.  

The spores will easily be swept away to other parts of your home, inducing negative health symptoms in you and your family. The Centers for Disease Control and Prevention state that mold alone can cause burning eyes, sore throat, coughing and wheezing, stuffy nose, and more unpleasant symptoms in a healthy homeowner. Homeowners with asthma or chronic lung diseases may find themselves even more at-risk for lung infections caused by inhaling mold or mildew spores. Mildew may produce similar effects, too.   

Pest Infestations  

Pests of all kinds tend to be drawn to homes with high humidity problems. Insects like ants, cockroaches, or termites can be particularly harmful. These pests can slowly destroy the very structure of your home from within. Some pests may even emit an odd, musty smell that will only draw more of them to your house.  

crawl space flooding

Leaks or Flooding  

You need to figure out the source of any leaks before they can split apart further and flood your house. These leaks can also contribute to flash floods within your crawl space. No homeowner wants to have to manually drain out gallons of water themselves. It is best to repair any leaks you see, no matter how tiny they are.  

This excess moisture can evaporate, creating an unpleasant, humid environment throughout your home. High humidity levels can create plenty of other problems as well.  

Warped or Uneven Floors   

Moisture buildup can start to warp the wooden floor beams used to support your floor. This can cause your floor to become uneven, dipping at random points where the floor beams have started to rot. Any mold or mildew growth may have accelerated this process as well.  

Uneven floors can create tripping hazards all around your home that can cause nasty injuries. These can be especially dangerous if you have any small children or elderly parents living with you. You will want to make sure to have these uneven floors repaired right away.  

Sticking Doors and Windows   

If it takes you more effort to open or close your doors and windows than usual, then it is possible that they are sticking to the doorways and windowsills respectively. Most homeowners will attribute this sticking to age, which can be the case for some households. However, if the true cause lies elsewhere, then sticking doors and windows can be a huge indicator of foundation damage.  

The foundation is located within the crawl space and is meant to keep your house’s infrastructure from leaning or swaying. Should moisture infiltrate the crawl space and damage the foundation, it can negatively affect most other parts of your home as well. Your doorways and windowsills could start to lean, effectively trapping the doors and windows in their respective frames. This causes them to become much harder to open or close.  

The Best Crawl Space Solutions

Your home deserves the best waterproofing solutions on the market. Tar Heel Basement Systems can offer your home the waterproofing protection you need with all our solutions below.  

Sump Pumps   

Coupled with an interior drainage system, sump pumps can collect any water that tries to infiltrate your crawl space and redirect it far away from your home. These machines require minimal maintenance, and it is also self-activating, which means you do not have to rush to turn it on if a storm hits. You can sit back and relax knowing that this machine will work hard to ensure your crawl space stays completely dry, no matter what the weather.   

cost to repair your crawl space

Vapor Barriers  

Thick vapor barriers can shield your crawl space from any moisture, mold or mildew spores, or other outside irritants.  

Vent Covers  

Once our experts are sure the rest of your crawl space is dry, we will then install sturdy plastic vent covers over any entrances to your crawl space. These vent covers are guaranteed never to rot or fly off. You can rest assured that no moisture will infiltrate your crawl space with these covers installed.   


Combating humidity can be tough. Installing a powerful dehumidifier into the crawl space will be just the waterproofing solution you need to ensure this small space stays completely dry. Moisture particles, mold or mildew spores, and other irritants can be easily filtered through this machine, allowing for cleaner, drier air to circulate all throughout the crawl space.  

Crawl Space Humidity


The encapsulation process is very thorough. It will tackle any potential issue your crawl space might face to ensure complete protection.  

  • Sump Pumps and Vapor Barriers  

If enough humidity builds up within the crawl space, then it is possible that it will start to condense into liquid drops. When this happens, it is very easy for your crawl space to flood from within. This is why it is important to install a sump pump in your crawl space. Coupled with an interior drainage system, these pumps can collect any moisture that forms and redirect it far from your crawl space.  

Vapor barriers are another great part of the encapsulation process. This thick barrier can prevent moisture from infiltrating your crawl space from any angle. You do not have to worry about any humidity being able to seep through, either. The barrier itself is also covered in an antimicrobial additive that discourages mold and mildew growth.  

  • Vent Covers and Dehumidifiers  

Much like the vapor barrier, our vent covers can protect your crawl space from any outside threats. Of course, rather than cover the inside of your crawl space, these covers will be securely attached to any open vents you might have. By sealing up these vents, your crawl space will no longer face any humidity issues whatsoever.  

Before we completely seal off your crawl space, however, our experts will install a dehumidifier first. This dehumidifier will ensure that if any humidity does slip through, it will be quickly filtered out. It will also keep the stagnant air inside the sealed crawl space nice and fresh as well.  

Maintaining the crawl space is vital to your home’s overall health. The systems and structures found inside are too crucial not to at least take measures to protect them. Let’s go over why the crawl space is so important to your home.  

  • Contains Vital Systems and Structures   

As its name implies, the crawl space tends to be just big enough for the average adult to crawl around in. Ceilings for these spaces can range anywhere between one to three feet high. Of course, even a larger crawl space can become cramped and difficult to navigate with all the vital systems scattered about.  

The crawl space’s main function is to store all your home’s important systems within it. This includes your plumbing, electrical wiring, HVAC system, insulation, and foundation. None of these systems should have any moisture even touching them, much less be submerged in a large flood of water. Moisture can wreck these systems, causing substantial damage not only to your crawl space but your entire home as well.  

  • The Foundation   

The foundation is an especially important structure for your home. It keeps the entire house standing steady and upright. Because many foundations nowadays tend to be made of concrete, you might think that there is no way that your own foundation could break apart.  

Unfortunately, moisture can easily shift or even crack your foundation from within. A damaged foundation can prove to be devastating for the rest of your home. You might find your doors or windowsills sticking or even your very walls starting to tilt. It can be extremely costly to repair these damages, so you need to ensure that your crawl space is protected to prevent this from happening in the first place.  

The crawl space is difficult for most people to access. You can risk accidentally damaging something important or even getting yourself stuck in this tight space. To make things easier on yourself, and ensure you get professional results, it’s helpful to leave any repairs to the crawl space experts at Tar Heel Basement Systems instead.  

  • Why DIY Repairs are Not Enough   

The average homeowner won’t have access to the right tools or experience to repair elements within the crawl space. Indeed, it is a cramped fit that does not offer much wiggle room, which leaves homeowners to struggle in the uncomfortable area. You might even find yourself stuck in this cramped space, or accidentally bump something that isn’t designed to be jarred.   

DIY solutions that home improvement stores sell tend to wear away over time. Buying the same solution to fix the same issues repeatedly soon develops into an unnecessary expense. That’s why it’s helpful to invest in more professional, permanent waterproofing solutions that work to protect your crawl space no matter what.  

  • Trust the Crawl Space Experts   

The crawl space experts at Tar Heel Basement Systems have all the right tools and know-how for any tough crawl space repair job. Our experts can navigate through these tiny spaces without disrupting any of the essential systems or structures within. We can also install powerful solutions that will work to permanently waterproof your home.  

Your crawl space is too important a space to neglect. That is why hiring the crawl space experts to inspect this space every year can be a huge help. If any problems do arise, we can quickly implement the best solutions to repair them before they become any worse.  

Contact the Crawl Space Experts at Tar Heel Basement Systems Today  

High humidity levels can create all sorts of issues within the crawl space. Because this tiny space contains some of your home’s most precious assets, it’s smart to address any issues right away. That’s best done when you call crawl space experts for help.  

Contact the crawl space experts at Tar Heel Basement Systems to schedule a free crawl space inspection today. We can also offer free quotes on all our powerful waterproofing solutions that can keep your home permanently dry and healthy. We serve all throughout the Raleigh and Winston-Salem areas.

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Fayetteville, NC 28311

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