Cracking of concrete is usually the first visible sign that something is changing under your slab, and in Des Moines it rarely stops on its own. Some cracks are harmless surface lines that need nothing more than a bead of filler. Others point to a sinking slab that will keep moving until someone addresses the soil beneath it. This guide helps you tell the difference, so you neither overpay to fix a cosmetic flaw nor underfix a structural problem. You'll learn why concrete cracks in central Iowa, how to read the warning signs, and which repair actually fits your situation.

What You'll Find in This Guide

Prefer to have a pro handle it? Concrete crack repair is one call away.

Why Concrete Cracking Happens Under Des Moines Slabs

If you're asking "why is my driveway cracking," the honest answer is that several different forces could be at work. Moreover, they leave different fingerprints, and reading those fingerprints correctly is the key to choosing the right fix.

The first culprit is shrinkage. Concrete loses moisture as it cures, and it shrinks slightly as it does. As a result, thin hairline cracks often appear within the first year of a slab's life. According to the Portland Cement Association, some cracking is an expected part of how concrete behaves. These shrinkage cracks tend to be narrow, shallow, and stable. They look bad, but they rarely mean trouble underneath.

The second culprit is Iowa weather. Water seeps into small cracks, freezes, and expands. Each freeze-thaw cycle pries the crack a little wider. Over a few central Iowa winters, a hairline crack can grow into a gap that swallows a car key. This is why timing matters: a small crack filled in September is a far smaller project than the same crack in April.

Why Soil Causes Concrete to Crack

The third culprit is the one that causes real damage, and it has nothing to do with the concrete itself. Much of the Des Moines metro sits on expansive clay soil. This clay swells when it absorbs water and shrinks as it dries out. Consequently, the ground under your slab moves with the seasons, and the slab moves with it. Add in water from a misdirected downspout washing soil out from under a driveway edge, and you get voids. Concrete is strong under compression but weak when it has to span a gap. Eventually it cracks and the broken section drops.

That last scenario matters because the crack is only a symptom. Filling it does nothing to stop the slab from continuing to sink. In that case, you're choosing between lifting the existing slab back into place or replacing it entirely, a decision we walk through in our comparison of a sunken slab versus a new slab. Understanding which of these three forces cracked your concrete tells you almost everything about the repair you need.

How to Tell If a Crack Is Structural or Just Cosmetic

This is the question that determines whether you spend a little or a lot, so it deserves a careful answer. Fortunately, you can learn a great deal from a five-minute inspection with nothing more than a tape measure and your own eyes.

Start with width. Hairline cracks, roughly the thickness of a credit card edge or less, are usually cosmetic. However, cracks wide enough to fit a pencil deserve more attention, especially if they've grown since you first noticed them. Take a photo with a coin next to the crack for scale, then compare again in a few months. Growth is a warning sign; stability is reassuring.

Next, check for vertical offset. Run your hand across the crack. If one side sits higher than the other, the slab has moved, and that points to settlement rather than simple shrinkage. Even a quarter inch of offset creates a trip hazard on a walkway, which matters if you have kids, older family members, or tenants using the path every day.

Signs That Point to a Settled Slab

Beyond width and offset, look at the pattern. A web of fine, shallow cracks across the surface, sometimes called map cracking, is typically a surface issue. In contrast, a single long crack that cuts across a driveway, or a corner section that has broken off and dropped, suggests the soil underneath gave way. Also watch for related clues: a slab pulling away from the garage floor, steps separating from the stoop, or water pooling where it used to drain.

Learning how to tell if a crack is structural is exactly the kind of judgment call where an in-person look helps, because soil conditions vary block by block across the metro. That said, the terminology alone can trip people up. Quotes throw around words like spalling, control joints, slabjacking, and epoxy injection as if everyone knows them. For that reason, we put together a plain-English glossary of crack repair terms so you can read any estimate and understand what each line actually buys you.

The core principle is simple. Cosmetic cracks are a sealing problem. Structural cracks with settlement are a soil problem wearing a concrete disguise.

Crack Filling, Epoxy, or Full Leveling: Matching the Fix to the Cause

Once you know what kind of crack you have, the repair options sort themselves out quickly. To put it simply, you fill cosmetic cracks, you inject structural cracks in stable slabs, and you lift settled slabs before you seal anything.

For cosmetic work, the choice usually comes down to concrete caulk versus filler. Flexible caulk suits narrow cracks and joints that need to move with the seasons. Pourable or trowelable fillers handle wider gaps and build back a flush surface. If you plan to fill cement cracks yourself on a stable walkway, either can work when you prep the crack properly. Clean out debris, remove loose material, and give the product a sound surface to grip.

The crack filler versus epoxy question comes up next. Fillers and sealants keep water out, which matters enormously in a freeze-thaw climate. Epoxy injection goes further: it structurally bonds the two sides of the crack back together. For example, a cracked but level garage floor slab might call for epoxy, while a seasonal joint crack in a patio just needs flexible sealant. Our Des Moines crack repair service covers both, and we tell you plainly which one your slab needs.

When Filling Alone Is the Wrong Answer

Here is the mistake that costs homeowners the most: filling cracks in a concrete driveway that is still sinking. The filler fails, the crack reopens wider, and the slab keeps dropping. In that situation, the slab needs lifting first, through mudjacking or polyurethane foam injection, and crack sealing second. Done in that order, the repair addresses the cause instead of the symptom.

Cost naturally follows the diagnosis. Simple filling is the smallest job, epoxy injection sits in the middle, and lifting a settled slab is the larger project. Even so, leveling often compares well against tearing out and repouring. According to HomeAdvisor, mudjacking typically runs 25% to 50% less than replacing a slab entirely. For national context, Angi and HomeAdvisor data put the average concrete leveling cost at $1,174, with a typical range of $630 to $1,723. Additionally, Angi notes that small mudjacking jobs may carry a minimum charge of around $500 even when the area is under 100 square feet. Your actual number depends on crack size, settlement, and access, which is why we break down each factor in our concrete crack repair cost guide.

Ready to Get Started?

Des Moines Concrete Leveling Pros repairs cracked concrete and lifts sunken slabs for homeowners across Des Moines and its immediate surrounding communities, from driveways and sidewalks to patios, steps, and garage floors. We look at the crack, the slab, and the soil underneath, then explain plainly whether filling, epoxy, or leveling fits your situation. Call us or send a request, and we'll take a look at what your concrete is telling you.