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How to Prevent Basement Leaks

By redirecting the water above ground and sealing out the moisture below, you'll give yourself peace of mind the next time rain is in the forecast.

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outside water run off presents problem in basement


Step 1: Watch an Overview Video

Step 2: Check for Outside Problems

Most basement moisture is the result of water run-off problems outside your home. Make sure that your gutters are clear, downspouts are in good working order and that rain water is being directed "away" from your home's foundation.

keep water directed away from foundation

Step 3: Repair Cracks

Once the water pressure has been removed from your home's foundation, you can seal it from the inside using a hydraulic cement.

If you have cracks in your basement that are allowing water to seep through, use a hammer and chisel to open them up. Undercut the crack by making the inside of the opening wider than it is at the surface so as the concrete hardens and expands, it will become locked. Once the crack has been opened, clean the area with water and a stiff brush. Now mix a small batch of hydraulic cement according to the instructions, and -- with gloves on -- roll the cement into a ball.

Dampen the area to be patched and press the cement into the crack to within 1/2" of the surface. Allow the first layer to dry, and then apply a second layer to match the surface you're repairing.

patch cracks with two layers of cement

Step 4: Use Water-Proofing Paint

Once all the foundation cracks are repaired, apply a water-proofing paint to seal out the moisture.

patching a leaky basement