How to Repair a Foundation Leak

Lead Image
  • 2-4 hours
  • Intermediate
  • 60-120
What You'll Need
Plastic sheets
Outdoor adhesive
Wire brush
Air pump
Epoxy resin

Repairing a foundation leak is not a hard or an expensive job, but it is very important. If leaks appear in the foundation and are left unfixed, major problems might arise in the future.

The two things you need to take into consideration when dealing with foundation leaks are the cause of the leak and the effect it has had on the foundation. Finding the root of the problem is even more important than dealing only with the results of the leak, such as cracks.

Step 1 - Get to the Root of Your Problem

In most cases, foundation leaks are the result of water penetrating the foundation, so preventing water from reaching the foundation is the best way to avoid leaks. Water gets into the soil and seeps into the foundation by infiltrating the ground nearby. Look for cracks that are moist with water, and walk around the house to pinpoint the area of penetration from the outside. If you discover water is leaking into the foundation from the inside (which likely means you have a plumbing problem), you'll need to use a different process.

Step 2 - Prepare the Foundation

A shovel digging up grass

Use the shovel to dig around your foundation. Dig about one foot (30cm) around the foundation and shovel some soil against it to create a slope. The sharper the slope, the better, as it will divert the water away from your home.

Step 3 - Apply Plastic Sheets

Lay the plastic sheets from your foundation outward. Attach them with an outdoor adhesive and wait for it to dry; then, place soil over the top. It’s recommended to use soil with a high clay content to prevent water from trickling through.

Step 4 - Deal with the Cracks

Close-up of a cracked wall

Now that you’ve dealt with the cause of these cracks, the damage itself must be fixed. Go to the basement and look for cracks, then use a wire brush and air pump to clean them. They need to be cleaned before they are mended because dirty cracks will not hold the filling.

The material used in the repair will depend on the size of the damage. Use epoxy resin if the cracks are small; use concrete if the cracks are large. Follow the directions for each material and be sure to use the right ratio of resin to concrete and water. Apply your chosen substance and then give the repair ample time to dry.

Remember that water has highly corrosive powers, so if you see any big cracks in your foundation, be sure to call a specialist to check for further damage. If the soil around your foundation has high water content, you may need to dig around the foundation and apply insulation to keep water away.

Inspecting the walls of your basement regularly for cracks and leaks will keep you aware of any problems before they get out of hand so you will be able to take proper measures before your foundation suffers serious damage.