A crack in the driveway or garage floor is easy to walk past for months — it’s not blocking anything, it’s not obviously dangerous, and concrete is supposed to last forever anyway, right? The problem is what happens underneath it while you’re not looking.
Why cracks form in the first place
Concrete cracks for a lot of ordinary reasons: shrinkage as it originally cured, the ground underneath settling slightly over time, tree roots pushing from below, temperature swings expanding and contracting the slab, or just the weight of vehicles over years. None of that means the concrete was installed wrong — it’s normal wear, and most driveways and garage floors develop some cracking eventually.
Why sealing them actually matters
A crack that just sits there dry isn’t doing much harm. The trouble starts when water gets into it:
- Water works its way under the slab, and repeated wetting and drying — or freezing, even in a mild Triangle winter — gradually widens the crack from the inside
- The base underneath can erode, which is how a small surface crack eventually turns into an uneven or sinking section
- Weeds and pests find an open crack to move into, widening it further as roots grow
- Garage floor cracks let moisture up into the space, which matters more if you’re storing anything on the floor
- A growing crack becomes a trip hazard, especially once one side starts sitting higher than the other
Sealing early is a five-minute fix. Letting it run for a few years is how you end up looking at a section of driveway that needs to be broken out and repoured.
Small crack, or a bigger problem?
Most cracks are cosmetic and a straightforward sealing job. A few signs are worth paying attention to before just filling it in:
- The crack is wider than about 1/4 inch
- One side sits higher than the other (a trip hazard, and a sign of movement underneath)
- It’s actively growing, not just sitting there the same size as last year
- It runs through a corner, doorway, or expansion joint in an unusual pattern
None of these automatically mean a major problem, but they’re worth a look before assuming a tube of sealant is the whole fix.
DIY vs. calling a handyman
A single hairline crack is a fine weekend project — clean it out, run a bead of concrete crack filler or polyurethane sealant, tool it smooth, and let it cure. It’s worth calling in help when there are multiple cracks to address, the crack shows one of the warning signs above, or you’d rather have someone look at the whole driveway or garage floor at once instead of one crack at a time.
What the job actually involves
- Cleaning debris, dirt, and loose concrete out of the crack
- Applying a flexible concrete crack filler or polyurethane sealant, sized to the crack width
- Tooling it smooth and level with the surrounding surface
- Letting it cure before any vehicle traffic
Got cracks in your driveway or garage floor in Apex, Cary, Holly Springs, or Raleigh? Get a free estimate or call/text (919) 704-0373 — it’s often worth bundling with a few other small maintenance items into one visit.
For garage floor crack repair, sealing and epoxy coating, see the Garage Floor Crack Repair service page.