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Does a Crawl Space Really Need to Be Vented?

Does a Crawl Space Really Need to Be Vented?

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Does your home have a crawl space? Crawl spaces are pretty common, and this is especially true in areas where homes with basements are a rarity.

Crawl spaces need to be designed properly to be safe. Do crawl spaces need to be vented for safety purposes?

Continue reading to learn about crawl space venting. You’ll learn everything that you need to know about this process.

Having all of the information about crawl space vents will help you to make good choices as a homeowner. You want to do everything you can to protect your property.

Are Crawl Spaces Supposed to Be Vented?

Yes, crawl spaces are supposed to be properly vented. If a crawl space isn’t ventilated, it’ll encounter many issues.

You need to have proper airflow in the crawl space area. Otherwise, it’s more likely that you’ll have issues with moisture building up under your home.

There are even building codes that have to do with crawl space ventilation in many areas. So for your home to be up to code, it might be necessary for your crawl space to be ventilated.

Even if you don’t have such requirements in your area, it’s still best to vent your crawl space. If you don’t do this, it’s simply going to make things worse.

Luckily, venting crawl spaces isn’t that hard. You’ll learn more about this later.

Do You Have to Vent a Crawl Space?

It’s absolutely necessary to have a vent in your crawl space. Not having a vent would prevent the crawl space from having any airflow.

When you have zero vents, moisture buildup is going to become quite an issue. You could wind up having so much moisture under your home that mold and mildew will begin to grow.

Having mold in your crawl space won’t be good. It’ll cause many problems that can even damage your home.

You might have issues with wood rot due to excessive moisture. The mold and mildew might get into your home through the vents, too.

This has the potential to make you sick. Simply put, proper ventilation is imperative when you have a crawl space. It’s important to ensure that your crawl space is designed properly so that everything will be okay.

How Many Vents Are Needed in a Crawl Space?

How many vents will be needed in a crawl space depends on how big the crawl space is. You must consider how much space you’re working with.

The generally accepted formula is that you should have one vent for every eight feet of the foundation wall. You can likely get away with stretching this to one vent for every ten feet of the foundation wall, though.

There might be local building codes that you’ll need to follow. You should look up specific information about building codes where you live to ensure that you’re doing everything by the book.

Many areas have building codes that require you to have one square foot of open ventilation for every 150 square feet of crawl space that you have. The rules could be slightly different in your area, and that means that you need to get official information.

It’s important to do things right so that you won’t violate building codes. Also, the guidelines are there for a reason to help people protect their homes and businesses.

What Size Are Crawl Space Vents?

Crawl space vents aren’t a specific size. You can buy vents and install them in your home as necessary.

Some crawl space vents might be 17 inches x 8 inches. Others might be 16 inches by 8 inches.

You can find crawl space vents that are a little on the small side. Then there are larger crawl space vents.

There are usually rules about having a certain amount of ventilation depending on how many square feet of crawl space you’re working with. So you must follow those rules.

Remember to follow the generally accepted rule of having one vent for every eight feet of the foundation wall. This is the safest way to do things, and it’ll help your crawl space to have proper airflow.

How Do Automatic Crawl Space Vents Work?

Automatic crawl space vents are being used more often these days. They’re quite a bit different than standard crawl space vents that you might be familiar with.

These are electronic crawl space vents that can open and close automatically. They use electricity and are designed to open and close when specific conditions are met.

For example, some automatic crawl space vents will automatically fully open whenever the temperature reaches 70 degrees Fahrenheit. The vents will then fully close when the temperature reaches 40 degrees Fahrenheit to protect your pipes and save energy.

If you choose to buy automatic vents, you’ll want to make sure to buy high-quality vents from a trusted company. These vents can stop working, and they need to be inspected thoroughly at least once per year.

In some ways, it’s easier to stick to using manual vents, but automatic vents can be convenient. So there are pros and cons to using these types of vents that you’ll have to consider.

How Many CFM Should a Crawl Space Have?

CFM is an abbreviation that stands for cubic feet per minute. It’s important to consider the CFM of your crawl space.

Determining the CFM that you need for your crawl space involves doing a little simple math. It’s all based on the measurements of your crawl space.

The simple formula is to multiply the length x width x height and then divide that number by fifteen. This gives you the number for how long it should take to ventilate the area with a fan in fifteen minutes.

Installing crawl space fans can be a good idea. It’ll help to solve issues with humidity.

If you live in an area that has high humidity levels, it’ll likely be helpful to install crawl space ventilation fans. These should make it less likely that you’ll deal with moisture issues in the future.

Just note that these fans can’t solve current issues with moisture. You’ll need to deal with those problems first and then install the fans to help prevent future problems.

Fix Your Crawl Space Issues

Fixing your crawl space issues is going to take a bit of effort. There might be problems that you’ll need to solve that involve doing more than just installing more vents.

You might have too much moisture present in the crawl space right now. Improving the airflow can solve that, but there might be other issues.

Earlier, you learned that improper ventilation can lead to issues with mold and mildew. Mold and mildew won’t just suddenly disappear because you installed a few vents.

You’re going to have to remove the mold yourself or call professionals to do it. Sadly, mold has the potential to be dangerous and it might make you sick.

If you’re going to remove the mold yourself, it’s best to wear protective clothing. You want to protect your eyes, hands, and lungs.

So wearing a mask, protective goggles, and gloves will be a must. Professionals typically wear coveralls or full protective suits to deal with mold problems.

Many products can be used to kill mold. You can use bleach, ammonia, vinegar, lime, and even hydrogen peroxide to get the job done.

As you’d expect, using chemicals in a small space such as a crawl space can be dangerous. If your crawl space isn’t ventilated properly, it’ll be even more dangerous than usual.

For most people, it’s best to call professionals and let them do the job. It’ll help you to get rid of mold so you won’t have to worry about it spreading and continuing to cause problems in your home.

Get Vents Installed

You can call a company to come to install vents in your crawl space, too. This will allow you to get the better ventilation that you need to keep your home safe.

Discuss your needs with local professionals so you can get all of the vents installed in the right spots. If you’re not sure how much ventilation you need to be up to code, you can rely on the experts to do things for you.

Generally, it’s easier to get help than it is to install your own vents. This is especially true if you don’t have the necessary skills or you’re not used to doing such work.

Getting this problem taken care of is the important thing. Whatever you choose to do, it’s best to act fast so that your lack of ventilation won’t come back to bite you.

Poor ventilation can lead to damage, and you might wind up having to pay for it later. Do what you need to do and install crawl space vents.

Final Thoughts

Knowing more about crawl spaces and the need for ventilation will help you. Having a crawl space that doesn’t have proper ventilation is dangerous.

It encourages mold and mildew growth. There will be substantial problems with humidity and moisture underneath your home.

The damage to your home could be immense if you don’t take action. You must install vents to ensure that your home is protected.

Doing this is also important from a building code perspective. So make sure that you get everything handled as soon as you’re able to.


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