- 1). Fill a spray bottle with water and spray the crack a few hours before you plan on patching it. A moistened crack will prevent the crack from drawing an excess amount of water to it.
- 2). Pour 2 cups of Portland cement into the pan. Add 1/4 cup water. Stir vigorously. Add another 1/4 cup water. Stir vigorously. Continue in this manner until the cement forms a thick paste.
- 3). Place your hand on the crack. It should be moist, but there should be no standing water on the crack. Wipe up any water if necessary.
- 4). Scoop up a wad of cement with your putty knife and pat it along the length of the crack. Repeat this process, forcing more cement into the crack. Rub a trowel against it, smoothing out the surface and forcing the cement deeper into the concrete. Allow the cement to dry for two hours.
- 5). Place a sheet of plastic over the crack and tape it in place, once the concrete has dried for at least two hours. Keep the sheet on the patched crack for five days and then remove. Sprinkle water over the patched area.
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