How to Prevent Water From Seeping Under a Slab Floor

an empty, well lit basement
  • 10-40 hours
  • Beginner
  • 200-500
What You'll Need

Most people have a slab floor in their basement. Generally it will be not be a problem, but water can seep under the slab. Follow these steps to prevent water seepage under your basement slab floor.

Step 1 - Digging

The most common cause of water seeping under the slab is a high water table. You must direct water away from the house. Dig so the ground around the house slopes away from the foundation. You should also dig an 18-inch trench away from the house which leads to a lower area.

Step 2 - Filling the Trench

Start with a 2-inch layer of gravel at the bottom of the trench. Put pipe at the top and fill around it with aggregate, going up to a level that is 6-inches below ground level. Add another 2-inch layer of gravel and fill the ditch with soil.

Step 3 - Around the House

Clean the gutters regularly to stop them from overflowing. Clean shrubbery the area around the foundation. Don’t give moisture an opportunity to pool around the foundation. Taking all these steps should prevent water from seeping directly under the slab floor.