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Got Water in Your Crawl Space? Here’s How to Fix It

If you have water leaking into your crawl space, it’s important to address the issue quickly, as it could have serious effects on your home and health.

Water in basement iStock

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Because the crawl space is a below-grade space under the house, you might think it’s normal to have a moist crawl space. After all, the ground gets wet and dry through the seasons and with weather patterns event.

But in fact, a dry crawl space is far superior and the sooner wet crawl space issues are addressed, the better.

What Causes Water in a Crawl Space?

Most times, water in the crawl space gets there one of three ways: a plumbing leak, water seepage from the surrounding soil (usually after heavy rain), or condensation. Humidity condenses on cold surfaces, like ducts, and drips onto the crawl space floor.

Puddles of water in the crawl space aren’t good, but the water itself won’t ruin your home. It’s the water vapor (or moisture) that causes rot, mold, energy loss, and attracts pests. And these problems don’t just stay in your crawl space.

As much as 50% of the air upstairs comes from below - this means mold spores, musty smells, and humid air that dust mites love.

3 Major Problems Caused by a Wet Crawl Space

Pooling water in the crawl space is obvious and so is damage such as mold and rot. What’s not as obvious is the ways a wet or damp crawl space can impact your health and the rest of the home.

1. Higher Energy Bills

A home with a dirt crawl space costs more to heat and cool. The reason for this is damp air takes more energy to heat or cool and more energy used means higher energy bills.

2. Mold

Mold loves moisture. And mold loves to eat dead organic materials, like wood, paper, and cardboard. The bad news is most crawl spaces have lots of moisture, as well as wood and other organic materials for mold to grow on.

Mold also likes to eat dead insects and there are usually lots of those in the crawl space too. Vents in the crawl space provide an open invitation for insects and pests. Vents also let in moisture, creating the ideal home for mold.

What’s worse is mold releases airborne spores that eventually make their way upstairs. Mold in your crawl space isn’t good for your health or your property value. Nobody wants to buy a house with mold.

3. Dust Mites & Pests

Dust mites thrive in humid environments, so they love homes with a dirt crawl space underneath. Dust mites are microscopic parasites that live in your bedding, carpet, and furniture.

Dust mite droppings float in the air and can trigger allergies and asthma. Other pests, like termites, spiders, mice, rats, and snakes love damp, dirt crawl spaces too.

Why is Water Getting into the Crawl Space?

The first step to fixing a wet crawl space is to determine what’s causing the water problem. There are three main causes of water in the crawl space:

  1. Surface water that gets into the crawl space is typically from roof drainage, overflowing gutters, grading issues, or leaky basement windows and window wells.
  2. Groundwater can cause problems for a crawl space in several ways. The soil around the foundation can become saturated after periods of heavy rain or snow. Water from the surrounding soil pushes against the walls of the foundation, eventually finding its way in.
  3. Plumbing issues, like a plumbing leak or a burst pipe, can introduce water into the crawl space. Even if you have a vapor barrier in your crawl space, the water will sit on top of the liner until it evaporates.

How to Keep the Crawl Space Dry

Adding a dehumidifier and sump pump system in the crawl space can prevent water and moisture damage.

If you have a crawl space that leaks when it rains—even if it’s only sometimes—getting the water problem under control should be the first step you take in fixing your overall crawl space problem.

Groundwater leaks and pooling water add humidity to your crawl space. A home with a dry crawl space is less attractive to mold, dust mites, termites, and other pests.

Getting rid of crawl space humidity can save you 15-25% on your heating and cooling costs. The exact savings will depend on several factors, including:

  • The size of your home
  • If there are ducts in the crawl space
  • Your local climate and soil conditions

Adding a sump pump is the first line of defense in keeping water out of the crawl space. It’s necessary to install a sump system with a sturdy sump liner, an airtight lid, and a reliable pump.

Who to Call for Water in Your Crawl Space:

The SmartSump System from Basement Systems is designed specifically for crawl spaces. A high-quality sump pump system with a battery backup pump is the best way to avoid common sump pump problems.

If you are worried about water in your crawl space, schedule a free crawl space evaluation from your local Basement Systems crawl space contractor.