Crawl Space Humidity Level

Excessive humidity in your crawl space can cause problems throughout your entire home. What is the ideal crawl space humidity level, and how can you achieve and maintain that level? Learn more about how encapsulating and dehumidifying this space can benefit your home and your family.

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Maintaining Your Crawl Space Humidity Level

A crawl space requires a specific amount of humidity to function properly. If your crawl space is outside that level of humidity, you may end up with a variety of issues pertaining to your crawl space and the rest of the home.

The thing is, many homeowners don’t know a lot about crawl space humidity levels. If you’re like many other homeowners, you might not actually have a plan in place regarding your crawl space humidity level, which means you’re probably letting it function however it naturally functions.

It’s important to pay attention to your crawl space humidity level if you want to make sure you’re maintaining a steady, stable home on all fronts. With this information and expert advice from JES, you can maintain a healthy crawl space humidity with minimum effort.

CFI checking humidity in crawl space

How Humidity Affects Your Crawl Space

Learn about the causes and dangers of crawl space humidity, as well as the ideal crawl space humidity level and how you can address this issue in your crawl space.

What should the moisture level be in your crawl space? A surprising number of homeowners don’t know the answer to this simple question. If you don’t know the ideal crawl space humidity level, how can you combat an unhealthy one?

The first step is learning the ideal humidity level for your crawl space. Here’s what you need to know. 

Knowing the Perfect Level

The right crawl space humidity level is an important factor to know when you’re trying to maintain your home’s crawl space integrity. As a general rule, you should typically keep your crawl space humidity level under 55%.

This level may change a little bit depending on where you live and the season you’re in. However, it’s a good idea to measure this humidity level year-round. You may need to do specific things to maintain your crawl space humidity in different seasons.

A hygrometer, which measures relative humidity, is a great tool for this. However, many people don’t have this tool and don’t know how to maintain this humidity level. A JES expert can help you understand the hygrometer reading and get a better understanding of your home’s humidity. 

Relative Humidity

It’s important to understand a little bit about relative humidity when you’re trying to understand crawl space humidity. Relative humidity measures how saturated the air is — at 100%, you get rain or thick condensation, because the air is too saturated to hold all the moisture inside it.

This is also an important concept to understand because it changes based on the temperature. Warm air can hold more water vapor than cool air, so the same amount of water vapor will result in higher relative humidity in cooler weather.

The relative humidity is the important measurement in a crawl space. Even if you don’t think there’s any reason for a high relative humidity measurement, it’s important to book a free inspection with JES to make sure everything is going well.

Low Crawl Space Humidity 

What if you have a very low level of humidity in your crawl space? Can crawl space humidity be too low? Technically, you can overdry a crawl space. If the crawl space moisture drops extremely low, you can dry out the wood, causing structural damage.

The good news is, it’s not really feasible for you to lower crawl space moisture that low. However, if you live in an extremely dry area, you may find that a dehumidifier for a crawl space drops the humidity lower than 30%, which is typically where humans start to feel uncomfortable. That can expand into the rest of your home as well.

It’s a good idea to keep your crawl space moisture between 30%-50% for maximum efficacy. A good dehumidifier can help you keep your crawl space dry when necessary, but make sure it maintains a healthy level of moisture. Talk to a JES expert if you’re worried about lowering the crawl space humidity too much. 

Why does your crawl space humidity even matter? Is there really anything wrong with having a high crawl space humidity? There absolutely is. High crawl space moisture levels can have serious effects on your home and your life.

What are those dangers? These are the biggest reasons you should try to adhere to acceptable moisture levels in a crawl space. 

Mold and Mildew

This is possibly the most well-known reason for maintaining a low crawl space humidity. Mold and mildew both thrive in areas of high humidity, and by maintaining a crawl space with high levels of moisture, you’re basically giving mold and mildew the go-ahead to start growing.

Typically, mold and mildew thrive in areas around 70% relative humidity. However, this is a loose number; mold can start growing at humidity levels much lower than that. This is especially true if you have a home with wet crawl space insulation or standing water, which can make a small section of the crawl space have higher humidity levels.

Overall, the possibility of mold and mildew should definitely drive you to make sure you’re maintaining acceptable moisture levels in your crawl space. If you’re already dealing with mold or mildew, a JES expert can help you fix it. 

Wood Rot

What happens when excess crawl space moisture gets into your structure? It causes serious problems with the wood that supports your home. This can manifest as wood rot, a specific fungal infection in your wood, or in other issues that have to do with wet wood.

These problems will quickly become issues with your home’s structure. That structure is essential when it comes to making sure you and your family stay safe. You definitely can’t afford to have ongoing structural problems in your home.

Whether you’re at risk of wood rot or you just have too much moisture in your home’s structure, that’s a problem you need to tackle as soon as possible. Talk to a JES expert to learn more about an answer for your crawl space moisture levels.

Health Concerns

One thing to remember is that high crawl space moisture levels don’t just impact your home on a structural basis. This is definitely an important thing to pay attention to, but crawl space humidity can actually cause health problems.

Those problems may stem from mold and mildew, which can have irritating or even toxic repercussions. However, even just the moisture in your home can rise through it, irritating sensitive skin and causing breathing problems for sensitive individuals.

The health concerns associated with high crawl space humidity is an important reason you should pay attention to it and address it as soon as possible. A JES expert will let you know what your next step should be.

Some people don’t know why their crawl space moisture levels could be too high. There are a variety of reasons for high crawl space humidity you may not have considered, and these can be incredibly important to fix before you install dehumidifiers for your crawl space.

Why do you have high crawl space humidity? Consider these possible reasons.

Flooding and Hydrostatic Pressure 

Hydrostatic pressure is the official name for the pressure exerted by water when it’s at rest. It’s an incredibly important part of understanding the pressure exerted on your basement or crawl space.

When the area around your home floods, the hydrostatic pressure also increases because there’s more water to press on the walls. This can cause too much strain on your walls, which may end up cracking to let in the water.

Your walls may have to endure some hydrostatic pressure, but you don’t have to resign yourself to cracked walls. Contact a JES expert to learn more about how you can avoid this pressure.

Open Crawl Space Vents 

As crawl spaces first became popular, the general concept was that a crawl space needed to “breathe.” To facilitate that, home designers started adding crawl space vents to crawl spaces.

However, over the years, we’ve discovered it’s not that simple. In fact, open crawl space vents can lead to higher levels of crawl space humidity. They can let in water from the outside and the cool air coming in can significantly increase the relative humidity.

That’s why open crawl space vents can actually be a problem. If you need to seal your crawl space vents, a JES expert can help you do that.

Wet Crawl Space Insulation

Your crawl space insulation can get wet for a variety of reasons. However, regardless of the reason, it’s important to realize that it’ll stay wet for a very long time.

When you have wet crawl space insulation, the only true fix is to replace it entirely. Otherwise, the moisture will just hang around, potentially even providing a great place for mold to grow.

Instead of just leaving wet crawl space insulation to grow, you should remove it and dehumidify the crawl space. A JES expert can help you down that road.

What’s the answer to high levels of crawl space humidity? In general, this is a multi-step process you have to be careful with. You can certainly reduce your crawl space moisture levels, but it may take some time.

These are the most common methods of reducing crawl space humidity. A JES expert can help you decide on the right one.

Crawl Space Encapsulation

Crawl space encapsulation is a must if you have a dirt crawl space floor or other ways for moisture to seep in regularly. This closes off all ways for moisture to come in.

Typically during crawl space encapsulation, an expert will lay down a thick 20-mil vapor barrier for your crawl space, keeping the moisture on the outside of the barrier. That’s the cleanest way to encapsulate.

This isn’t a weekend project, and it requires an expert’s touch. If you want to do crawl space encapsulation right, it’s important that you contact JES to learn more about your options.

Sealing Crawl Space Doors and Vents 

As part of encapsulation, you should make sure crawl space doors and vents have the proper treatment. That means ensuring that crawl space doors close tightly, with no cracks, and vents are sealed.

Remember, open vents don’t work to keep your crawl space dry, and they might actually increase humidity. That’s just one reason you may want to seal your crawl space vents for good.

The right option can vary from home to home. What works best for you will likely not work best for people in similar but not identical situations. Trust a JES expert to do a full inspection of your home and let you know what path you should pursue.

Dehumidifiers for Your Crawl Space

In some cases, you may need dehumidifiers for the crawl space. This can be useful if you have extremely high levels of moisture in the area as a whole, which tends to move to your crawl space.

If you do need a dehumidifier for your crawl space, it’s important that you choose an energy-effective one. That way, you won’t run up your electric bill too high.

Some people may need a dehumidifier for their crawl space, while others may be able to get by just with encapsulating the space and maintaining a strong vapor barrier for the crawl space. If you’re not sure which one will work best for you, talk to a JES expert to learn more about your options.

Talk to a JES Expert to Learn More About Acceptable Moisture Levels in Your Crawl Space

There is definitely a range of acceptable moisture levels in your crawl space, which means there are many places your crawl space can rest. You may need a dehumidifier to get to that point or you may not; it depends on your home.

This uncertainty is just one of the reasons you should rely on a JES expert to learn more about your options. Your perfect solution may not be the same as someone else’s perfect solution. A JES expert can tailor this solution to fit your unique needs.

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