How to fix concrete cracks

Remember this? “Step on a crack, break your mother’s back.” Let’s just fill the crack and avoid hurting people altogether. Read on to learn how to fix concrete cracks.

What You'll Need

  • Slab®

    Textured, elastomeric caulk for long-lasting concrete crack repair

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  • 1

    Gather tools

    You’ll need:
    • Slab
    • Filler Rope™ or other backer rod
    • Drill-mounted brush or stiff bristled brush (grunt grunt “More power!”) for cleaning out the crack
    • Caulk gun
    • Utility knife for opening the caulking cartridge
    • Putty knife or foam brushes for tooling (or your trusty finger)
    • Damp rags for clean-up
    • Some jammin’ crack sealing tunes to make the work go faster

  • 2

    Clean the crack

    If you want your caulking job to stick and stretch for years to come, make sure you clean out old caulk, dirt, sidewalk chalk, dandelions, ant colonies and other contaminants.

  • 3

    Insert Filler Rope™

    Any crack that’s deeper than 1/2” and wider than 1/4” needs Sashco’s Filler Rope™ or some other type of backer rod so the caulking will properly stretch, and so you use less caulking.

    Backer Rod and Slab

  • 4

    Apply the caulk

    Be smooth about it now. A steady hand will save you clean-up later. Make sure the bead is at least 1/4” thick but no more than 1/2” thick to allow it to stretch correctly (too thin and it’ll tear, too thick and it’ll be too rigid).

    Slab After Application Driveway Expansion Joint

  • 5

    Tool (smooth) the caulk

    Use a damp foam brush, a putty knife, or your trusty finger to create a good-lookin’ bead and ensure the caulk is sticking to the sides of the joint properly.

    Slab Expansion Joint Tooling

  • 6

    Clean up

    Use soap and water to clean up skin and tools. Stand back and admire your handy work. Invite your neighbors over to show them, too.

 Special Tip

You shouldn’t drive or walk on those newly filled cracks for at least 24 hours, so put a spare piece of plywood over top of the caulk during that time to avoid getting tire tracks and footprints on it. If you do it right, you should only need to read this "How to fix concrete cracks" guide once.