Fixing Cracks In Concrete Walls

By: Joseph Truini (Page 1 of 3)

1. Use a wire brush to clean the crack of all dirt, grease and loose grit. Then vacuum up any residual dust and debris.

2. Tap in a 3-in. finishing nail every 12 in. along the entire crack. The nails will be used to align the injection ports.

3. Mix together equal amounts of the two-part epoxy crack sealer using a clean putty knife and scrap board.

4. Apply crack sealer to the injection port flange, then slip the port over the nail and press it to the wall.

5. Spread a 2-in.-wide band of sealer along the entire crack and over the round flange of each injection port.

6. Inject the liquid epoxy into the port with a caulking gun. Squeeze until epoxy drips from the port above.

7. Cap off the first injection port with a plastic plug, then move up to the next port and inject more liquid epoxy.

8. Once the filler has cured for five days, use a hacksaw to cut off the protruding plastic ports from the wall.

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What You'll Learn:

Concrete consists primarily of cement, sand, gravel and water. As the water in the slurry evaporates, the remaining ingredients cure into a hard, monolithic slab. Unfortunately, the curing process causes the concrete to shrink slightly, often resulting in hairline cracks. Larger stress cracks occur when a house settles or the ground beneath it shifts. These types of cracks typically don't threaten the structural integrity of the house, but they do create an entry point for groundwater, insects and radon gas. Here, we'll show you a simple, effective way to patch cracks in poured- concrete walls.

If you notice large, recurring cracks or bulging walls at your house, don't try to fix these conditions yourself. The cracks might indicate a more serious structural problem; call in a structural engineer for an in-depth evaluation.