Ideal Crawl Space Humidity

Crawl space humidity can be difficult to maintain. What should the humidity be in a crawl space, and how can JES help you accomplish that level?

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Outside humidity is always changing. Whether you live in a city with very high outside humidity or your city tends toward having lower humidity, you should always be thinking about the impact that humidity has on your home.

Moisture is a huge problem for home structures, and crawl space humidity can seriously damage your home structure. What should the humidity be in a crawl space? How do you make sure your crawl space reaches that humidity? These are very common questions for homeowners with humidity issues.

Crawl Space Repair in Virginia, Maryland, and DC

Understanding Humidity & Crawl Space Moisture

If you’re looking to achieve the right crawl space humidity level, it’s a good idea to have a starting point. That way, you’ll at least know a little more about the inner workings of your home. Here’s everything you need to know about humidity and your crawl space.

The important point of order for understanding humidity is the “relative humidity.” It’s a confusing concept that’s hard to understand, and the formulas used to create the number you see on the news can be very difficult to determine.

The good news for you is that you don’t need to know all the ins and outs. You just need to know the absolute basics.

Water in the Air 

Relative humidity is a measurement that describes how much water is in the air relative to how much water the air can hold maximum. That means an area at 60% humidity is holding 60% of the water it could hold at most.

Warmer air can hold more water than cooler air. That means the summertime air can hold more water than air during the winter. Although the relative humidity may not change much, it’s common for higher humidity to be more uncomfortable in warmer climates because there’s more water in the air.

If you live in a coastal climate, you’ll typically have higher relative humidity in the area. That’s because the air around you absorbs the water from the ocean.

Warm Air Cooling

Because warmer air can hold more water than cooler air, that can actually lead to problems when the two collide. It’s a very complicated process to determine the actual relative humidity when two types of air collide, but what’s important to remember is that it can very quickly turn into condensation.

Essentially, when warm air cools drastically, the relative humidity shoots up. Relative humidity above 100% turns into condensation because the air is so saturated with moisture that it has to leech out somehow.

That means if you’re in a situation where warmer air is cooling down quickly, such as a crawl space with open vents letting in cool external air, you’re almost invariably going to end up handling condensation. It’s important to pay attention to this facet of the process.

The Right Relative Humidity Year-Round

Before you look for the ideal crawl space humidity level, you should think about the right humidity in your house as a whole. Typically, humans do best in humidity levels ranging from 30-60%, with most people feeling most comfortable around 50-60%.

So what should humidity be in the crawl space? That’s a difficult question to answer. However, 60% humidity in the crawl space should probably be the top end of your ideal crawl space humidity level. Most people aim for around 55% to avoid any unforeseen problems.

Of course, this may change around the year as the external relative humidity changes with the temperature. Depending on your space, you may need to look into purchasing a dehumidifier for maximum comfort.

If you do have a high humidity level in your crawl space, you may end up with a variety of problems. That’s why it’s so important to keep an eye on your crawl space humidity. The ideal humidity for a crawl space needs to be at the forefront of any changes you make.

At the very least, you need to make sure you’re maintaining a low humidity level. Otherwise, you may run into these problems.

Mold and Mildew

Typically, you’ll see that mold needs at least a 70% relative humidity level to grow. The thing is, however, this is a pretty loose number. You may actually see mold and mildew starting to grow at lower than 70% relative humidity.

How is this possible? If the relative humidity of a surface is different than the relative humidity of the air in your crawl space, it can actually create an ideal situation for the mold and mildew in the area even if you’re measuring relative humidity of less than 70%.

It’s important to monitor your crawl space’s ideal relative humidity to prevent structural damage overall. If you’ve never taken any steps to identify your crawl space’s ideal relative humidity, it’s a good idea to request a free inspection from JES to do just that.

Wood Rot

Wood rot is caused by a fungus that grows best in cool, moist environments. If you have an overly moist environment in your crawl space, you may end up with wood rot all around your foundation, which can be extremely worrying for your structure.

If you’re dealing with wood rot, you may notice bouncy floors, a slightly musty odor, and very high humidity in the rest of your home. These signs all point toward a problem that you should try to tackle as soon as you can.

Wood rot left unchecked can seriously damage your home’s foundation. Anyone who’s started to notice these warning signs of wood rot should schedule a free home foundation inspection to make sure there aren’t any problems.

Higher Electricity Bills

You may not have considered this, but a high level of humidity in your home can actually lead to higher electricity bills. That means fixing the high humidity levels could actually save you money, albeit over a long period of time.

People tend to feel more uncomfortable when a home has high relative humidity, even if the temperature is at an otherwise comfortable temperature. This discomfort may lead to an attempt to “cool off” by turning up the air conditioning.

Although it might be expensive to fix the high humidity in your crawl space, it can actually pay for itself if you end up being able to turn the air conditioning down. These lower electricity bills can certainly make the whole process worth your while.

You shouldn’t just ask, “What should crawl space humidity be?” The answer to the perfect crawl space humidity doesn’t matter if you don’t know how to get there. There are many reasons you may have a crawl space humidity level that’s too high.

Instead of just trying to read a crawl space humidity chart, consider these fixes that can actually help you maintain the right humidity.

Crawl Space Encapsulation

This is the preferred method if you have a crawl space with a dirt floor. Unfortunately, there’s no way to stop a dirt floor from giving off moisture. You can only dry out the very top layer of soil; underneath, you’re always going to find moist soil.

That’s why you should consider crawl space encapsulation. With this method, a professional lays down a thick vapor barrier between the soil and the rest of the crawl space, ensuring that the moisture from the soil doesn’t actually impact the crawl space.

If you have a crawl space with a dirt floor, this is really the only way to make sure the moisture from the dirt floor doesn’t impact the rest of the crawl space. Contact a JES professional today to learn more about this option.

Close Crawl Space Vents

The concept of how to properly vent a crawl space has come up regularly ever since crawl spaces started. At the beginning of crawl space construction, people typically thought that a crawl space needed to “breathe,” which is why they installed crawl space vents.

However, because of the problems that occur when cool air meets warm air and vice versa, this may actually lead to a higher crawl space humidity level. You may actually end up with humidity problems because of your crawl space vents.

The only answer to the question of how to properly vent a crawl space is that you shouldn’t. Close the crawl space vents you have if possible, and contact a JES professional if you’re not sure how to do it.

Install a Dehumidifier

A dehumidifier can be a great option if you’re consistently having crawl space humidity problems. After all, that’s exactly what a dehumidifier is for.

Remember that some humidity in the air is good. You don’t want to completely dry out the air in your crawl space. You just want to keep the humidity level low enough that you won’t run into mold, wood rot, and other structural problems.

A JES expert can help you understand which dehumidifiers will work best for you. If you’re going to run your dehumidifier regularly, an expert can also suggest a great energy-efficient dehumidifier for your needs.

If you have a dirt crawl space, you’re going to struggle with crawl space humidity until you take actual steps to avoid it. That means you need to pursue crawl space encapsulation. It’s the only way to get your crawl space to the ideal crawl space humidity level.

There are many reasons to pursue crawl space encapsulation. These are the best reasons for contacting a JES professional to talk about it today.

Remove Crawl Space Vents

As mentioned before, crawl space vents are typically much more trouble than they’re worth. These typically only contribute to crawl space humidity rather than reducing it.

If you’re going to reduce crawl space humidity, you’re going to have to remove the vents in your crawl space. Because encapsulation focuses on completely removing the introduction of humidity into the area, it can seal those vents or remove them entirely.

It’s a good idea to pursue crawl space encapsulation if only to remove the vents that may be causing excess moisture in your crawl space. In fact, even if you don’t have a dirt floor, you should take steps to remove crawl space vents.

Avoid Condensation

Condensation is a very common occurrence in crawl spaces that aren’t encapsulated. Remember, when the relative humidity in an area reaches higher than 100%, condensation will form on some surfaces.

The ideal crawl space humidity level is much lower than 100%. However, if the soil continues to pump moisture into the air, you’re going to end up with condensation problems eventually.

With a vapor barrier, common in crawl space encapsulation, you can avoid having those soil moisture problems. Instead, the moisture will stay in the soil and outside of the vapor barrier. 

Reduce Risk of Structural Damage 

Constant moisture isn’t good for any structure, whether it’s wood, stone, brick or any other material. The moisture that comes out of the soil will continually wear away at the structure under your home.

With a vapor barrier and full crawl space encapsulation, you won’t have to worry as much about the high crawl space humidity. That will make it easier for you to maintain a strong structure and foundation.

Although this won’t completely prevent structural damage on its own, it’s an important first step. If you don’t have a crawl space vapor barrier, contact JES to get more information about encapsulating your crawl space.

Learn More From a JES Crawl Space Expert

Have you realized the importance of maintaining ideal humidity in your crawl space? It’s important that you keep to a 30-60% humidity in your crawl space, ideally leveling out at around 55%.

No matter what your current crawl space humidity is, you can get it to that magical number. All you have to do is get in touch with a JES expert. You can talk about your current crawl space issues and get more information about what to do if you want to fix them.

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