Keeping Water Out of Sevierville Crawl Spaces

Crawl space waterproofing in Sevierville usually means an interior perimeter drain and a sump pump, costing $2,000 to $5,000 (Knoxville-area range). The drain catches water where it seeps in at the footing, the sump pumps it outside, and only then should the crawl be lined and sealed.

Where does the water under a Sevierville house come from?

• The slope. Much of Sevierville is hilly. Rain that soaks in uphill moves through the soil toward the foundation.
• Groundwater. In East Tennessee's Valley and Ridge, deep weathered soil and rock hold and carry a lot of water (U.S. Geological Survey).
• The roof. Gutters that overflow or downspouts that empty at the wall put water right where the crawl is lowest.
• Heavy storms. The Knoxville airport station averages 14.3 days a year with an inch of rain or more (NOAA).

Try the outside fixes first

Clean the gutters, extend downspouts several feet from the house, and check that soil slopes away from the foundation. These cost little and sometimes solve a damp crawl on their own. If water still appears after a heavy rain, the next step is inside.

How an interior drain and sump work

1. A shallow trench is dug along the inside of the foundation wall, usually on the uphill side or all the way around.
2. Perforated pipe in gravel collects water where it enters.
3. The pipe runs to a sealed sump basin at the low point of the crawl.
4. A pump sends the water outside through a discharge line that ends well away from the house.
5. The liner goes over the top, and the crawl is sealed and dried.

What it costs and what comes next

Drainage with a sump runs $2,000 to $5,000 depending on the length of drain, how much water comes in and how far the discharge has to go. It is usually the first stage of a full encapsulation. The Sevierville crawl space repair price guide shows the other stages and three example projects.