Can A Crawl Space Flood? [5 Prevention Tips]

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While it's not the most popular part of the house, your crawl space is essential to the function and structural integrity of your home. Given its importance in your home, you may wonder: Can it flood? How do I prevent it from flooding? We've done the research and consulted with experts to give you the answers to your questions.

Yes, a crawl space can flood from heavy rains, drainage or plumbing problems, leaky pipes, overwatering plants, and more. There are six effective ways to prevent crawl space flooding, namely:

  1. Check for and resolve drainage issues.
  2. Seal gaps and cracks.
  3. Properly grade the land around your home.
  4. Install a sump pump.
  5. Encapsulate your crawl space.

There's much more to explore about floods in crawl spaces. Keep reading as we dive in further and explore why it happens, how to prevent it, and how to fix it when it happens.

Standing water in crawl space, Can A Crawl Space Flood? [5 Prevention Tips]

Common Causes of Crawl Space Flooding

Before we get into more details on how to prevent crawl space flooding, let's take a look into why it happens in the first place.

Water can come from above and below the ground, which can lead to dangerous floods. Here are a few of the most common causes of crawl space flooding:

Drainage problems

crawlspace basement oil tank and plumbing

Drainage systems are designed to lead water away from your home. However, they can get clogged or damaged over time. For instance, leaves can clog up your gutters and prevent water from flowing away from your home. An improperly installed or placed downspout can also lead water towards your crawl space.

Faulty drainage systems may also get overwhelmed by heavy rains and storms, resulting in excess water in the crawl space.

Plumbing issues

Problems with your plumbing don't just affect the rooms in your home. They can also lead water down to your crawl space. For instance, broken or worn-out pipes are frequent culprits for crawl space floods.

Improper land grading

The land around your home should slope away from the foundation of the building. Otherwise, water on the ground from rain and thawed snow will be directed to and pool in your crawl space.

Gaps and cracks in the foundation

Cracks in the foundation of your home can lead to water entering your crawl space. Left untreated, this will eventually lead to flooding.

Sewer backup

Sewage from clogged sewer lines can fill up and flood your crawl space. This can cause unpleasant odors and pose serious threats to your and your family's health.

Crawlspace full of water

5 Ways to Prevent Crawl Space Flooding

While there are many issues that can cause crawl space flooding, the upside is that there are also plenty of ways to prevent it. Here are the best ways to prevent crawl space flooding:

1. Check for and resolve drainage issues

Inspecting your gutters regularly is a good habit that will not only defend against crawl space flooding but also prevent structural damage and health hazards. Make sure to inspect and clean your gutters at least once a month.

Check for any existing issues and remove leaves and other debris. Damage to your roofing and dirty yards can also lead to airborne debris, so keep these areas of your home well-maintained.

Your downspouts are also a huge part of your home's drainage system, which means they can also contribute to crawl space flooding. Check your downspouts for any signs of clogging, leaks, or damage.

Another important step is to make sure your downspouts are at least four to ten feet away from your home's foundation. Otherwise, they'll lead rain runoff towards it. If your downspouts are next to or too close to your foundation, you can purchase a downspout extension.

Click here to see this downspout extension on Amazon.

2. Seal gaps and cracks 

Sealing cracks in your crawl space does not only improve its appearance. It also significantly lessens its risk of flooding. When cracks are sealed, they won't provide a passageway for water to enter and pool in your crawl space. 

Inspect your crawl space for any visible cracks or gaps. You can easily seal small cracks by yourself with an epoxy sealer or an epoxy injector. However, cracks that are wider than 1/4 inches should be checked by an engineer. These could indicate severe structural damage. 

3. Properly grade the land around your home 

The grade of the landscape around your home should be sloping downwards - away from the foundation of your home. This way, water won't flow towards your crawl space. The general rule is that there should be a slope of 6 inches or 1-inch per foot for the first 10 feet.

If the grading of your landscape is level or leads towards your foundation, you can fix it by adding soil to the area next to the foundation. You can also consult with a landscaping professional to improve your land grading.

4. Install a sump pump 

A sump pump is a device that removes water from a sump pit or a sump basin, which collects water from drains or from the soil. When excess water comes into the crawl space, the sump pump will pump it into a drainage area away from your home. 

If you're in an flood-prone area, it may be a good idea to install a sump pump. This will help prevent flooding and water damage. 

Check out this sump pump on Amazon.

5. Encapsulate your crawl space 

Crawl space encapsulation is a process that involves sealing the walls and floor of your crawl space with an airtight polyethylene plastic that acts as a moisture barrier. After sealing the crawl space, the gaps are filled with foam insulation. Professionals also install a dehumidifier to further protect against excess moisture. 

Besides protecting your crawl space against flooding, encapsulation also prevents mold growth and pest infestations. It also improves the function of your HVAC systems and helps extend their longevity. 

Keep in mind that encapsulation may be quite expensive - it can cost up to $15,000 depending on the size and condition of your crawl space.

How do I fix a flooded crawl space?

If your crawl space has already flooded, don't worry. Follow these steps to dry out your crawl space:

  1. Remove all wet and moldy materials.
  2. Remove the standing water using a broom or a wet-dry vac. If this is not enough, use a pump.
  3. Use a dehumidifier to remove remaining moisture. Leave it on for a few hours. 

Crawl space fully encapsulated with thermoregulatory blankets and dimple board

How much does it cost to fix flooding in a crawl space?

sump pump manhole with water back up viewed with a flashlight

Extreme flooding in your crawl space will require major repairs. The total cost for this will depend on the extent of damage, the size of your crawl space, the cleaning services required, and the waterproofing or encapsulation services offered.

On average, crawl space repairs after flooding can cost anywhere from $1,500 to $10,000.

Does homeowners insurance cover water in crawl space?

Homeowners' insurance policies provide coverage for the structure of the home, which includes your crawl space. However, insurance coverage varies greatly. Some policies may cover water damage to your crawl space under certain circumstances - for instance, if pipe leaks caused the damage.

Some may also cover specific costs such as costs for structural damage. Others may not provide coverage for this. Be sure to consult with your insurance provider to check if you have coverage for issues with your crawl space.

Will a crawl space dry out on its own?

A flooded and sub pumped crawlspace vapor barrior dirty job

Technically, a crawl space will dry out on its own eventually. But you shouldn't let it air dry after flooding or even when it's damp. Your crawl space can quickly absorb moisture, which can be the perfect breeding ground for mold, mildew, pest habitats, and nasty odors. In the worst-case scenario, it can eventually compromise the structural integrity of your home and cause the crawl space to erode.

Instead of letting your crawl space air dry, use a dehumidifier to completely eliminate moisture from your crawl space after a flood. Using a heat lamp and electric fans can also speed up the drying process.

In Closing

The crawl space in your home can be susceptible to floods. But there are plenty of ways to prevent flooding and make sure water flows away from the foundation of your home. Protecting your crawl space against flooding now will not only save you time and money in the future, but it will also keep your home structure secure and safeguard you and your family against health hazards.

Enjoyed this post? Check out more of our informative articles related to this topic:

Can You Convert A Crawl Space Into A Basement?

Are Cellars Designed To Flood?

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