Water Is Coming Through a Crack in a Concrete Slab

Identification

• Moisture can get into your home by leaking into your basement or crawl space in the form of rainwater or snow. Excess moisture can also come in through vapor diffusion as it moves through concrete or other solid materials and evaporates. According to the United States Environmental Protection Agency, or EPA, standing water in your basement is usually caused by cracks or leaks in your home's foundation.

Causes

• Improper drainage is the most common cause of excess moisture inside your home. The ground around your home should slope away from the foundation. It is often necessary to regrade your yard to be sure water doesn't come into the foundation through cracks that have formed over time. Moisture may also come into your home by migrating through your foundation and evaporating, which is common in homes with dirt floor basements or in those that do not have an adequate moisture barrier in place.

Effects

• Excess moisture inside your home can cause problems such as mold growth. Mold grows when materials such as concrete, tile, wood or drywall receive a constant supply of moisture. Once fungal spores land on areas of moisture, they can germinate and grow within 24 hours. Mold is not always easy to find and can occur in hidden places, making it difficult to diagnose. When water comes in through cracks in the slab, mold could begin to grow underneath carpet or carpet padding laid over a concrete floor. Mold growth can eventually cause structural damage to your home as well, as mold digests the material it grows on over time. This could result in costly home repairs.

Solutions

• Placing a moisture barrier over your dirt floor basement will help reduce moisture moving through the foundation. Plastic works well as a moisture barrier when it is placed over at least 4 inches of gravel. Regrade your yard if sloping soil is allowing water to run into your foundation. Examine your downspouts and gutters outside your home, making sure no clogs are allowing water to seep inside. Footing drains that become clogged or blocked are also common sources of water leaks.