How to Stop Water Leaks in Your Basement Walls: 10 Actionable Steps

By: Diana Rodriguez-Zaba
Updated on: February 15, 2024

Whether it serves as a second den, laundry room or extra storage space, it shouldn’t leak. Basement walls shouldn’t be streaked with wet stains, and they aren’t supposed to serve as breeding grounds for unhealthy mold growth.

When the basement starts to look and smell like a cave, do you know how to stop a water leak in the basement wall?

It can make the difference between reclaiming dry ground and calling our teams for flooded basement water removal. All you need are basic handyman skills, a few tools and affordable materials.

Keep reading for actionable steps!

How to Fix a Basement Wall Leak From the Inside

Leaky basement walls don’t mean your house isn’t well-built. Chicago home foundations and basements deal with hydrostatic pressure from the area’s fluctuating water table and lateral pressure from our compact clay soil. The combination of time and nature can make any basement leak.

A combination of simple tools, your DIY talents and these 10 steps can take care of most problems downstairs and help prevent basement leaks in heavy rain.

1. Give Yourself Room

If you’re like most Chicago homeowners, you have plenty of stuff stored in the basement. Move shelving and appliances several feet away from leaky walls so that you have plenty of room to work.

2. Assemble Your Gear

The best way to fix a leaking basement wall starts with assembling these tools and materials.

  • Safety goggles and latex gloves
  • Drop cloths
  • Hammer and chisel
  • Wire brush
  • Compressed air
  • Mortar trowel
  • Hydraulic cement

3. Locate the Leak

When we’re asked about how to stop a water leak in a basement wall, we always advise homeowners to follow the drip and look for more than one source. You may be dealing with several entry points where water seeps in.

4. Chisel and Inspect

Once you find a leak’s location, spread your drop cloth under the area, and put on your safety goggles. Carefully open and inspect the leaking crack or void to determine the extent of the damage. Be on the lookout for any signs of mold growth. It’s very common for unhealthy fungus to breed in leaking basement walls.

5. Widen the Crack

Using your hammer and chisel, open the crack to a quarter-inch width. Undercut the edges making them as square as possible. Hydraulic cement expands as it cures, and it needs a well-defined area to form a tight seal.

6. Clean and Prep

Clean out the opened crack with your wire brush. Be sure to thoroughly sweep away all debris. Hydraulic cement seals best on a clean surface, so finish up with bursts from a can of compressed air. It’s especially important to wear safety goggles during this step.

7. Mix the Sealant

Put on your latex gloves, and mix the sealant according to package instructions. Most hydraulic cement products are simple to mix and use, but only blend a little bit at a time. The material sets in 10 to 15 minutes, so mix small handfuls, and work in sections.

8. Apply the Cement

Make sure you’re wearing latex gloves to protect your skin. Push the freshly mixed hydraulic cement deep into the crack. Use your mortar trowel to apply the sealant, and firmly press it deep into the crack with your hand. Work quickly from the bottom of the crack to the top.

9. Finish Up and Clean Up

Once the crack is completely filled, smooth surfaces with the mortar trowel as you spread a top layer of sealant up, down and across the crack. As the hydraulic cement cures and dries, don’t let it set on your tools. Give everything a good wash, and gather up your drop cloth for disposal.

10. Double-Check Your Work

You can’t see through those basement walls, so don’t assume you’ve solved the problem with one patch job. Keep a close eye on the area that leaked, make basement wall inspection a routine, and develop strategies that can prevent future basement flooding.

Dealing with a Basement Water Leak in Chicago? We Can Help

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The next time it pours here in Chicagoland, we hope our how-to guide helps you avoid flooded basement water removal.

If torrential storms or frozen burst pipes turn the downstairs into an indoor pool, call us right away. We’ve seen it all from backed-up sump pumps to broken washing machines.

When you need the best basement flooding cleanup company in Chicago and the suburbs, you can depend on ServiceMaster Restoration by Zaba.

Call now for 24 hour emergency help: 773-647-1985