Crawl Space Moisture Control: How It Works

What Can Happen When Crawl Space Moisture Is Not Addressed?

• Damage to the Wood Framing: Wood absorbs water, and damp wood can develop wood rot, which weakens the framing over time. Metal in the crawl space can rust and corrode as well.
• Mold and Mildew: Mold and mildew grow in damp places. They look and smell unpleasant, and mold can bother people with allergies or asthma.
• Indoor Air Quality: Air from the crawl space moves up into the living spaces. If that air carries moisture and mold spores, it affects the air in your home.

How Is Crawl Space Moisture Controlled?

Vapor Barriers

Installing vapor barriers is a common way to keep ground moisture out of the crawl space air. They are large plastic sheets that cover the ground and block moisture rising from the soil.

Dehumidifiers

A dedicated dehumidifier under the house helps keep humidity in a healthy range. It draws in air, removes moisture and blows the drier air back out. Running a dehumidifier in the crawl space makes it a less inviting place for mold and mildew.

Sump Pumps

In areas prone to flooding or with a high water table, such as the Carolina coast, a sump pump removes water that collects in the crawl space. If standing water is a common problem, a sump pump in the crawl space, with a battery backup for power outages, carries that water out of the house.

What Are the Steps to Control Crawl Space Moisture?

Step 1: Assess the Situation

The first step is to assess the extent of moisture in your crawl space and identify the primary sources of water intrusion. Take a flashlight and examine the area under your house. How moist is your crawl space, and where could the water come from? What you find decides which methods fit.

Side note: If you would rather not go into your crawl space, our free inspection covers it. We also provide full crawl space encapsulation, which turns a damp crawl space into a cleaner, drier one. Our encapsulation warranty requires annual maintenance at the owner’s expense; the terms and their conditions are on our warranties page.

Step 2: Choosing the Right Solution

Based on what the assessment finds, choose the moisture control methods that fit. Depending on the condition of your crawl space, that may be a vapor barrier, a dehumidifier, a sump pump or a combination.

Step 3: Installation and Action

Whether it is a vapor barrier, a dehumidifier or a sump pump, the system works best when it is installed correctly.

Preventive Measures to Keep Moisture Under Control

Routine Inspections

Check your crawl space regularly for signs of moisture or damage, so small problems are found early. Keep an eye out for leaks, check your moisture barriers, and ensure that your dehumidifier and sump pump (if you have them) work correctly.

How Do You Maintain Crawl Space Moisture Control Systems?

Moisture control systems need regular care to keep working. Clean your dehumidifier’s filter, check the sump pump’s operation before the rainy season, and repair any tears or damage to your vapor barrier.

Why Is a Dry Crawl Space Important?

Controlling moisture in your crawl space helps protect the structure of your home and the air you breathe in it. Knowing where the moisture comes from and how it is controlled is the first step toward a dry crawl space.

If you have questions about moisture in your crawl space, contact our team. We serve towns across the Carolinas.