How to Get Rid of Moisture in Crawl Space

If your home has a crawlspace, it’s crucial to keep it free and dry.

So, how to get rid of moisture in a crawl space? In order to eliminate moisture inside your crawl space, you can use the following tips: insulate the house foundation, make better drainage, cover the floors, use a dehumidifier or use electric fans.

Read more below.

A Clean Isolated Crawl Space

A damp place is the best breeding ground for mildew and mold.

Other than that, it might be an invitation to the termites not to mention some vermin that like damp and dark spaces. These may include spiders, rats, snakes, and some unwanted guests.

There would be times when your crawl space might become damp. So, you have to know the ways on how to keep it dry.

You may use the following advice to eliminate humidity in your crawl space:

1. Insulated Your Foundation

Using moisture proof insulation, make sure to insulate the exposed walls of your foundation. You can tape the seams to avoid moisture and air from passing through.

You may also insulate rim joists, which sit on the foundation walls as well as caulk seams to avoid any moisturized air flow.

2. Make Better Drainage

Improving drainage around your home will prevent the rainwater from seeping under the foundation.

Make sure that your soil will be graded at .5” per foot. Buy additional soil if necessary to enhance the grade.

Although you have gutters, doing this would prevent the rainwater from entering the crawl space through your foundation.

3. Cover the Floor

Another way of drying your crawl space and preventing damp issues is covering the floor with heavy-duty plastic that is called moisture barrier.

If the barrier is thicker, the better it would be.

Whenever you are covering the floor you must do it in continuous runs. Punctures or accidental holes won’t cause a barrier to be ineffective. But, it’s possible if there aren’t any gaping holes.

4. Use the Best Dehumidifier

A lot of people have achieved success in drying out their crawl space with a dehumidifier.

There are also some specialty commercial grade dehumidifiers, which are manufactured for this kind of purpose.

The only thing that you should do is to plug in the device and let it run for a few hours. In many circumstances, you’ll notice a substantial reduction in the level of moisture.

5. Consider Using an Electric Fan

If your crawl space has lots of ventilation and became damp, you might dry it using a huge electric fan. You can place your electric fan at the crawl space’s opening.

Just turn it on. Then, leave that to run for at least ten hours. There are times that moving air around inside would let it dry instead quickly.

6. Cap the Interior of Your Foundation Wall

Capping your foundation wall’s interior with strips of plastic sheeting. After that, add galvanized flashing makes an effective moisture barrier. In addition to that, galvanized flashing will combat the termites.

Such tips to dry out crawl space would keep your house safe. These will help you avoid any costly damage.

Also, consider buying a good hygrometer for your crawl space. This will let you know the level of humidity all the time.

What Causes a Wet Crawl Space?

Water in the crawl spaces might be a larger issue than you could think of. Even if the place is your home’s remote area, the water that gathers there could cause problems on each floor once mold forms.

There are two things that mold requires to survive and these include darkness and moisture.

The mold may also spread through a ventilation system, which may cause health issues and could grow on joists and piers that can cause some structural problems.

Gutter and Downspouts

Gutter and downspouts issues are some of the devastating things about water in crawl space. It is not because of lack of access, damage caused or impending health issues, but it is actually the fact that the entire ordeal might have been prevented easily.

It is for the reason that the huge cause of leaks is improper downspout aiming and not cleaning out the gutters. If you have to hire a plumber, you must choose the best one in your area to get results.

Downspouts must be pointed away from the foundation of your home and may be accompanied by a two-foot splash block at its bottom, which guides the water away.

If a home does not have downspout or has something that’s faced at the house, storms will wash away the soil’s grade eventually and direct the water on the bypass to the basement.

It can’t be stressed enough on how essential slopes away from a home are in preventing any damage on the foundation. The properly sloped grading around the crawl space may help prevent the water from entering your house. The remedy of the poor sloping grade is actually to build it up.

See to it that you have the slope of at least 6 to 8 inches away from the foundation wall, which extends for the first six to eight feet. The grade must be checked each spring once the ground thaws to determine if the winter washed away or caused the structure’s shifting.


Crawl space leaks may also originate from the inside of your home. The thing with water is that it’ll always trickle down, so though pipes have burst somewhere near the upstairs bathroom, it might find the last resting spot below your house.

The simplest way to detect the broken pipe is through taking your home’s visual inventory, searching for some obvious wet spots.

Once you suspect that you have broken pipes, yet cannot locate the leak, just contact the plumbing service for you to pinpoint the exact place of the loose or ruptured pipe connection.

Human Errors

There are times that hazards may be caused by some human errors, particularly when the hose is left operating near the house’s side or when someone overwaters their shrubs.

Not just excessive watering causes your plants to die, but also it makes a water source that most homes are not equipped to deal with. Ensure that your flowerbed is equipped with good base layers to avoid water from skipping past the roots. It will also keep your crawl space dry.

There are times that leaks come from the outside of your home. It may be either from the broken city line or the water that comes from the underground. The city municipalities would have to come on the site to repair any issues on their end and there might be some things that can cause subterranean water to form the following:

  • Torrential storm makes just excessive water for your drainage system for handling and causing pools of water that might seep deep to the soil.
  • The underground drains are made to carry the water away from your house have become plugged, damaged or have an insufficient slope.
  • The foundation walls making a dam, which causes the surface water to seep underground and find the crawl space’s opening.

Is a Wet Crawl Space Bad?

Many people deal with crawl space issues but they never really take time in addressing these concerns. Sadly, failure to fix these problems with your crawl space right away will make you experience damages to your home and many health issues.

Ignoring these problems longer will result in higher costs of fixing the damage. Thousands of dollars worth of damage in your property can happen when you don’t fix problems immediately.

There are many issues that can occur in an uncared for and neglected space, most of which can lead to serious damages to your house. One of these is none other than moisture.

When you can smell mold in your house or your crawl space is wet, there is a high chance that you are dealing with moisture problems. Opening the vents in your crawl space can allow moisture to get inside that can cause mildew, mold, wood rot, and dust mites.

In addition to that, moisture increases once it evaporates inside.

Once it happens, moisture will go through your home’s walls, insulation, and floors, which can ruin your property. The longer you wait for repair it means that the issue will get worse and would just cost you more money.

If there’s dirt inside, it is just best that you should clean it up, particularly if you have open crawl space vent. Exposed dirt actually absorbs and attracts moisture.

Once dirt dries up quickly, it causes the levels of humidity to rise in your house. Once the levels of humidity in your house change, you will likely turn up your air conditioning unit to a much cooler temperature that can result in high electric bills.