How to Repair a Cracked Concrete Slab: DIY Fix vs. When to Call a Pro

Cracked concrete is one of the most common calls we get — and the good news is that most cracked concrete slab repair jobs don’t require a whole new pour. The key is knowing which kind of crack you’re looking at, and whether your cracked concrete slab repair is a simple DIY fix or a job for a pro.

Close-up of a hairline crack, a common case for cracked concrete slab repair
A hairline crack like this is usually cosmetic — not a sign you need major repair.

Step 1: Figure Out What Kind of Cracked Concrete Slab Repair You Need

Hairline cracks — Thin, surface-level lines, often from normal concrete shrinkage as it cures. Usually cosmetic and not a structural concern.

Settlement cracks — Wider cracks, sometimes with one side of the slab slightly higher or lower than the other. These indicate the ground underneath has shifted or settled unevenly — common in areas with Ventura County’s expansive clay soil.

Heaving cracks — The opposite of settlement: a section of the slab has been pushed upward, often by tree roots, poor drainage, or soil expansion after heavy rain.

Structural cracks — Cracks running through a load-bearing area (like a driveway that supports vehicle weight), especially if they’re widening over time, extend through the full depth of the slab, or come with visible separation between sections.

Deep widespread crack across a concrete driveway needing cracked concrete slab repair
Wide, spreading cracks like this usually point to settlement — not just surface wear.

Step 2: Simple Tests You Can Do Yourself

  • Width test: A crack under 1/8 inch is generally cosmetic. Wider than that, especially if it’s growing, warrants a closer look.
  • Level test: Place a level or straight board across the crack. If one side sits noticeably higher, you’re dealing with settlement or heaving, not just surface shrinkage.
  • Water test: Does water pool at the crack after rain, or drain away? Pooling suggests a drainage or grading issue that will keep making the problem worse.
  • Trend test: Take a photo with a ruler next to the crack and check back in a few months. Cracks that are actively widening point to an ongoing movement issue, not a one-time event.

When DIY Is a Reasonable Option

For hairline or minor cosmetic cracks that aren’t widening, a basic concrete crack filler or polyurethane caulk from a hardware store can prevent water intrusion and hold you over. This is maintenance, not a real fix — think of it like caulking a bathroom, not patching a foundation.

When to Call a Concrete Contractor

  • The crack is wider than 1/4 inch or clearly widening
  • One side of the slab is visibly higher or lower than the other
  • The crack runs through a driveway, garage slab, or other load-bearing area
  • Water consistently pools at or near the crack
  • You see multiple cracks radiating from one point, or a network of cracking rather than a single line
  • The slab is more than 15-20 years old and showing several of the signs above at once

Settlement and heaving cracks in particular are a sign of what’s happening under the slab, not just the surface — patching the crack without addressing the soil movement usually means the same crack (or a worse one nearby) comes back within a year or two.

What Professional Cracked Concrete Slab Repair Involves

Depending on severity, a contractor may recommend:

  • Routing and sealing — for stable cracks that just need to be protected from water and debris
  • Slab jacking or leveling — for settlement issues, lifting the sunken section back into place
  • Sawcut and patch — removing and re-pouring the affected section
  • Full replacement — when a slab has multiple structural cracks or the base underneath has failed
Freshly poured concrete slab after a full sawcut and re-pour repair
A full sawcut-and-patch or re-pour gives you a clean, level slab when the damage runs too deep to patch.

If you’re dealing with a cracked driveway in Camarillo or anywhere else in Ventura County, we’re happy to take a look and give you an honest read on whether it’s a simple patch or something bigger. Contact us for a free assessment — we’ll tell you straight if it’s a DIY-fine situation, no upsell needed.

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