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Condensation in the crawl space

Crawl Space Condensation

Condensation and excessive humidity in the crawl space are common problems, but many homeowners may not know how these issues started or how to fix them.

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condensation in crawl spaces

Crawl space condensation means you have a moisture problem in your crawl space. This leads to structural damage, mold and allergy problems, and most importantly – your family & home’s safety. Learn more by reading below or contact JES today for a free crawl space inspection.

Crawl Space Condensation – Crawl Space Moisture Control in VA, MD, and DC

Identifying & Repairing Crawl Space Issues Related To Moisture, Condensation, & Humidity

Do You Have Crawl Space Condensation?

The Biggest Problems with Condensation

There are several problems that condensation causes. Here are some of the biggest problems you might see in your crawl space and the rest of your home if you don’t fix your condensation concerns.

Standing Water  

Standing water is a huge problem you need to address as soon as you see it. There are many ways standing water can exist in a crawl space. For example, you may notice it across the crawl space or only in certain spaces, which might be because your crawl space has a tilt toward a specific side of the space. 

There are also many reasons for standing crawl space water, from active leaks to condensation dripping onto the floor, and many ways you can fix it. First off, it’s important to fix any active leaks that are happening in your crawl space. Once you’ve removed the source of standing crawl space water, a sump pump may be a useful way to remove the water, whether you use it for a short period of time or you install one for good.

Condensation Droplets

Another problem that happens relates to the actual condensation droplets. Condensation occurs when the humidity in a specific area is higher than 100%. That additional humidity needs somewhere to go.

Outside, it will become rain. Inside, it usually condenses on an area that’s cooler than the surrounding area, which may be a cold water pipe or just a wall that tends to be cooler. 

It’s easier to overlook condensation than standing water because standing water tends to be more obvious, but both of these problems are incredibly important. The good news is that there are ways to avoid condensation, both by removing the source of high humidity and by installing insulation around areas that are more likely to experience condensation.

High Humidity

Lastly, many areas that have condensation also have high levels of humidity. That’s mostly because condensation forms when the relative humidity of a location is above 100%. That means the rest of the area will probably have very high levels of humidity, which can have its own issues aside from condensation and condensation droplets.

The only real way you can avoid high levels of humidity is to remove the source. You’ll probably want to install a vapor barrier and cover all crawl space vents and doors. If you still experience high levels of humidity in your crawl space, you might need to also install an energy-efficient dehumidifier in the crawl space.

Mold and Mildew 

Wherever high levels of humidity flourish, you’ll also find a lot of mold and mildew. Unfortunately, mold and mildew tend to thrive in levels of humidity higher than 60-70%. If your crawl space has a level of humidity that’s that high or higher, it’s very common to see a significant amount of mold and mildew in the crawl space.

Remember that if you have condensation in any area of the crawl space, you might end up with mold and mildew too. Even if certain areas don’t have high levels of moisture, mold and mildew can grow around individual moisture droplets. That’s why it’s important to handle crawl space condensation at the source.

Destroyed Insulation

Whenever water gets into insulation, it essentially ruins the insulation’s ability to function. Think about it this way: You wouldn’t put on a wet coat, so why would you use a “wet coat” for your walls or pipes? Water destroys insulation and makes it so the insulation no longer works, at least until you replace it with new insulation.

This destroyed insulation can be very frustrating to handle, especially because many people don’t even realize they have insulation that’s destroyed. You could be wasting money on your home’s heating and cooling system because your insulation in the crawl space doesn’t work, which means your home’s essentially unable to keep itself warm or cold.

Wood Rot

Wood rot is a type of fungus that can be similar to mold and mildew, but it attacks areas of your home very differently. If your home’s suffering from wood rot, you could have bouncy, sagging, soft wood in the crawl space. At extreme levels, wood rot can even cause your home to collapse, although it takes a very long time for this to happen.

The thing is, wood rot also thrives in very high humidity, and it’s incredibly difficult to remove once it’s sprouted in your home. The best way to avoid wood rot and avoid the significant expense that comes from having it in your home is to make sure you avoid condensation in the first place. That’s how you make sure your home doesn’t end up with wood concerns in general.

The Stack Effect

Condensation typically comes from open crawl spaces, and possibly the biggest frustration open crawl spaces cause is the stack effect. This describes the effect that occurs when there’s an entrance for air in the crawl space and in the attic; air enters in the crawl space, warms up, then rises through the home until it exits through the crawl space.

Although this might not be a concern on its own, it’s definitely a concern when it occurs with open-air vents. When crawl space vents are open, you’re much more likely to have mold, mildew, pests, and other dirty air in the crawl space. Through the stack effect, that dirty air starts to proliferate throughout your home, which can lead to significant increases in respiratory concerns and allergies.

 Pests and Insects  

No matter how small the holes in your crawl space vents are, there are at least some pests and insects that will be able to make it through. Many crawl space vents have surprisingly large holes, making it very easy for all sorts of pests to come through and make a home in your crawl space, which they often do.

Pests and insects are difficult to get rid of because they can reproduce so fast. If any sort of pest or insect gets into your home and lays eggs or has a litter, you’ll end up with these pests for years and sometimes even longer. When you have open crawl space vents, you’re also going to have pests in your crawl space. The only way to avoid pests and insects in your crawl space is to close off your crawl space entirely. 

High Energy Bills 

One of the biggest problems you might encounter if you don’t have a closed crawl space is high energy bills. It’s extremely common for people to have very high energy bills with any open crawl space for two reasons: the introduction of moisture into the crawl space and the fact that crawl space vents leak warm or cool air out into the world, rather than keeping the warm or cool air in the home where it belongs.

The first point comes from the fact that high-moisture air is much more difficult to condition than low-moisture air. That means you often have to turn your air conditioning up, which increases your energy bills. The second point comes from the fact that crawl space vents don’t discriminate between air that’s coming in and air that’s going out, so your home’s air can go out as easily as outside air can come in.

Open Crawl Space Vents

In the cooler months, the air outside your home might be cooler than the air inside, but during the warmer months, outside air is almost always warmer than inside air. The ground maintains a near-steady temperature year-round, which can keep your crawl space cool. However, what happens when a vented crawl space allows air inside?

Not only does this warm air come inside your home, raising your cooling bill, but it also creates crawl space condensation because of the different ways in which cool and warm air carry humidity. This condensation can damage insulation and ductwork, cause wood rot and mildew, and increase your electricity bill.

Venting your crawl space could be costing you money! A vented crawl space could raise your electric bill by 15-25%

Dirt Crawl Spaces

Some home builders opt for dirt crawl spaces over concrete crawl spaces because they’re cheaper and easier to install. Dirt crawl spaces don’t require the same amount of work as concrete crawl spaces, and that’s one reason they’ve become so popular over the years. However, the problem is that dirt crawl spaces are also rife with problems and are more likely to cause crawl space condensation issues.

Unfortunately, you’ll never be able to get rid of crawl space moisture if you have an uncovered dirt crawl space because it’ll just rise through the dirt. Even if the top of the dirt looks dry, the dirt underneath isn’t, and that means you’re going to end up with higher crawl space moisture. Plus, as air moves up through your home, it’ll take dust particles with it, which are likely to amplify allergies and respiratory issues in you and your family members.

More than 50% Of The Air You Breathe Comes From Your Crawl Space

torn vapor barrier in crawl space

Poor Moisture Barriers

Moisture barriers are an important part of crafting a low-moisture crawl space. Especially if you have a dirt crawl space, these moisture barriers, also called “vapor barriers,” can be very helpful in ensuring moisture stays out of your space. It’s the best way to avoid many crawl space moisture problems. However, if you just go for the minimum mandatory moisture barrier, you’re doing yourself a disservice.

The truth is that only a high-quality 20-mil vapor barrier will keep water vapor out of your crawl space and out of the rest of your home. Otherwise, you might find that water permeates through the barrier or that it becomes torn and disheveled, which will require you to clean the crawl space. Low-quality vapor barriers, which include many vapor barrier types under 20-mil, are generally ineffective in this regard. That’s why JES only uses top-tier 20-mil CrawlSeal vapor barriers for clients.

If you have a low-quality moisture barrier, you might have more problems than with no barrier at all.

CFI meeting with homeowners

What’s Your Next Step?

When you’re dealing with crawl space moisture, there are a lot of potential options. You may need crawl space encapsulation, you might need to install an energy-efficient dehumidifier, and you might also need to consider pest prevention. JES can help you get your start.

No matter what your crawl space moisture problems look like, it’s a good idea to request an inspection from JES. A JES crawl space repair expert will enter your crawl space, take a look at the problems you’re experiencing, and recommend a tested and proven solution.

Crawl Space Condensation Solutions

If we find that you have a crawl space humidity problem we may recommend one of these solutions: CrawlSeal, crawl space vent covers or JES Dehumidifier dehumidifier.

These products aren’t always the solution to your crawl space humidity problem, so it’s important to talk with an expert to find the best solution for your crawl space.

Our certified professional crawl space repair specialists will work with you, every step of the way, to design the best crawl space repair solution for your home’s condensation problem. We want to hear your questions and concerns; after all, we are here to help you find the best solution for your crawl space humidity problem.

Moisture, Condensation, and Humidity FAQ

Moisture, condensation, and humidity are all problems you can have with a dirt crawl space. Here’s how you can avoid these concerns for good.

It can be tempting to try and ignore the bit of dampness you find in your crawl space. After all, it’s easy to blame an influx of moisture on an ongoing storm or on weeks of heavy precipitation. Doing so, however, can set you up for long-term damage.  

Check for Leaks 

If you notice dampness or standing water in your crawl space, you likely have some manner of leak on your hands. It’s possible that the leak in question may have originated outside of your home, or it may be coming from your pipes. Either way, you need to inspect your home thoroughly to find the source of the dampness and to patch it accordingly. If you choose to ignore crawl space dampness, you may find yourself contending with significant structural issues later down the line. Some of the most common problems related to leaks in your crawl space include: 

  • Mold growth 
  • Unpleasant and persistent smells 
  • Split floor joists 
  • Sagging floors 
  • Fogged windows 
  • Warped door frames and windowsills  

The Dangers of a Damp Crawl Space 

It is in your best interest to treat these issues seriously and to try and attend to the source of your home’s damage instead of just the symptoms. Attempting, for example, to remove mold from your home without investing in crawl space repairs may result in that mold’s reappearance in a few weeks or months. 

In short, you should not ignore that little bit of water you find in your crawl space after a storm. If you notice signs of a leak in your crawl space, you can reach out to the professional contractors working in your area. Together, you can inspect your home and determine whether or not you have any substantial damage on your hands. If you do, you can request a free quote citing the cost of potential repairs and, in turn, better determine what you want your repair budget to look like.

If your crawl space is unfinished or otherwise has a dirt floor, you may not want to start your waterproofing process with an encapsulation job. Instead, you should consider whether or not you want to finish off the space. A simple crawl space lining, for example, can make your space more comfortable while also providing it with a simple protection against invasive tree roots, unwanted infestations, and even light water damage. 

Check the Soil 

You always, however, want to try and limit the amount of dirt-to-air exposure that your crawl space has. When you live in a home with a dirt-floor crawl space, you open yourself up to more structural risks. Shifting soils can disrupt the placement of your structural supports, and critters like termites and even moles can more easily make their way into your space. While some of these creatures aren’t inherently malevolent, they can still cause a lot of damage throughout your crawl space. Flooding is more common in homes with dirt floor crawl spaces, as these spaces often lack the protection they need to ward away water and prevent long-term damage to the aforementioned structural supports, not to mention an attached foundation. 

Protecting Your Dirt Crawl Space 

Note that there are also some things you will want to avoid doing in a dirt crawl space. For example, do not install vents in a crawl space with a dirt floor. Dirt floors already breathe or allow moisture and gases into your home on a regular basis. By installing vents, you put your crawl space at greater risk for significant water damage. 

If you’re purchasing a home that has crawl space vents, or if you haven’t taken note of your own vents before, you can close these vents off with exterior accessories designed to improve the water seal around your space.

It is never a bad idea to invest in waterproofing measures that can protect your home. Encapsulation can help you lower your energy bills, lower your risk of sagging floors, and keep your home healthier while also helping prevent water damage in your crawl space and subsequent structural supports. 

Always Encapsulate 

The process of encapsulating your crawl space allows you to protect your home against unwanted moisture. To encapsulate your crawl space, you can cover the walls, roof, and floor with a dense layer of plastic-like material. In doing so, you can create a tight seal within your space, preventing both water and most gas particles from making their way inside. 

Your Home Encapsulation Options 

Your options, when you’re deciding what materials to encapsulate your crawl space with, will vary in thickness and in size, with costs rising depending on the density of the product you’re more interested in. Note that while installing plastic vapor barriers during the encapsulation process may require special equipment, this waterproofing measure does not use electricity or other means to protect your home. Rather, it is the sheer density of the material at work that drives water away from your crawl space. 

The cost of encapsulating your crawl space will vary based on the materials you or an attending professional want to bring into the space. The size of your crawl space may also increase the cost of an installation job. Note that you will also have the option, during the encapsulation process, to invest in additional waterproofing measures that can help increase the lifespan of the plastic barriers you use. Doing so can increase the cost of your installation but can also help you prevent additional damage later down the line.

You do have the option, upon discovering moisture in your crawl space, to encapsulate the space on your own. It is not, however, always in your best interest to try and take on this challenge. 

More Costly  

Many homeowners believe that DIY solutions can save them money on the repairs they may need to protect their homes. In fact, trying to encapsulate your crawl space without assistance from a professional can cost you a pretty penny. You will, after all, have to purchase materials and any specialty tools you may need to help with the installation. If you happen to make any mistakes, as well, you’ll still have to pay for professional assistance—and more than you would have had you reached out for help in the first place. Professionals who come into your home after you’ve attempted a DIY encapsulation solution will have to remove your work before installing their own, costing you significantly more in labor. 

More Damaging 

There is always a chance that in investing in a DIY encapsulation job, you may not address the core problem allowing moisture into your crawl space. If you fail to address this problem, then employing DIY encapsulation will only put a bandage on a larger problem. While you might think your crawl space is safe after your work is complete, the cracks or leaks allowing moisture into your home may grow larger and put the overall structural integrity of both your crawl space and your foundation at risk. 

It is in your best interest to at least seek out the opinion of a professional contractor serving your region. This way, you can better understand why your crawl space is leaking and whether or not encapsulation may help you restore your home’s value.


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