Why Concrete Cracks: What You Need to Know

Concrete is one of the most durable and widely used construction materials in the world, but even the strongest concrete can crack. At VIP Concrete, we often get asked: “Why does concrete crack?” The answer is simple and complex. While cracking is common, it can result from a variety of factors. The good news? Most cracks are preventable or manageable with the right installation and care.

1. Shrinkage During the Curing Process

One of the most common causes of concrete cracking is shrinkage. As concrete dries and cures, the moisture in the mix begins to evaporate. This causes the concrete to shrink slightly. If the shrinkage is restrained in any way—by the subgrade, reinforcement, or even temperature—it can cause cracking. These are called shrinkage cracks, and they’re often hairline but can appear soon after the pour.

2. Improper Subgrade Preparation

Concrete is only as strong as the base it’s built on. If the subgrade (the soil or gravel underneath) isn’t properly compacted or graded, the concrete slab can settle unevenly. This leads to stress points that can cause cracks, especially in driveways, walkways, and patios.

3. Excess Water in the Mix

Too much water weakens the concrete. A wet mix may make concrete easier to pour, but it also increases the risk of cracking. As the excess water evaporates, the slab can shrink more than expected, resulting in surface or structural cracks.

4. Rapid Drying

Concrete needs time to cure slowly and evenly. If it dries too quickly—due to high heat, wind, or low humidity—cracks can form on the surface. That’s why proper curing techniques (such as wet curing or applying curing compound) are so important.

5. Lack of Control Joints

Control joints are intentional grooves cut into the concrete to control where cracks form. Without them, cracks may occur randomly. At VIP Concrete, we always incorporate properly spaced control joints to help manage shrinkage and direct natural cracking to less visible areas.

6. Heavy Loads or Structural Stress

Concrete has high compressive strength—but it can still be damaged under extreme weight or impact. Parking heavy vehicles or equipment on areas not designed for it can stress the slab and cause cracking over time.

Are All Cracks a Problem?

Not necessarily. Some minor cracks are purely cosmetic and don’t impact the structural integrity of your concrete. Others may indicate deeper issues or worsening conditions. Whether or not a crack needs repair depends on the type, location, and purpose of the slab.

Repair vs. Replacement: Practical Options

In many cases—especially in commercial or warehouse settings—not every crack requires full replacement. If the concrete is otherwise stable, we can often fill and grind cracks to create a smoother, more functional surface without tearing out the entire slab. This is a cost-effective solution for clients who need an improved finish or even surface but don’t require structural reconstruction.

If you're unsure whether a crack needs repair, grinding, or replacement, our team can assess it and recommend the best option for your needs and budget.

How VIP Concrete Helps Prevent (and Repair) Cracks

We take every measure to minimize cracking from the start by:

• Preparing a strong, stable subgrade

• Using proper water-to-cement ratios

• Installing control joints• Applying quality curing techniques

• Reinforcing concrete when needed

We also offer crack repair solutions including epoxy injection, joint fill, grind & seal, and resurfacing—tailored to your needs and usage requirements.

Have Cracks Already? We Can Help.

Whether you’re dealing with new cracks or want to prevent them on your next project, VIP Concrete is here to help. We offer expert repair solutions and professional concrete installation throughout Las Vegas and surrounding areas.

📞 Contact us today at (702) 381-2121 or visit www.vipconcretelv.com to schedule a consultation.