hairline cracks (1)

DIY Mastery: Hairline Concrete Crack Repair Made Easy

Hey there, Des Moines homeowners! Are you noticing small cracks creeping across your concrete surfaces? Don’t worry, you’re not alone. These hairline cracks are common, but the good news is, fixing them can be a simple DIY project. In this guide, we’ll walk you through easy steps to repair these cracks and keep your concrete looking great.

Understanding Hairline Cracks in Concrete

Hairline cracks in concrete are thin surface fractures that typically measure less than 0.1 inches in width. They may look like fine lines mapped out across your concrete surfaces. These cracks are common in both new and older concrete installations. They don’t usually signify structural damage but can detract from your home’s aesthetic appeal.

Why They Occur

Several factors can cause hairline cracks in Des Moines. The most common is the natural settling of the soil under the concrete. As the ground shifts slightly over time, the concrete may crack under the pressure. Seasonal temperature changes in Iowa, which range from hot, humid summers to freezing winters, cause concrete to expand and contract. This constant movement can create stress fractures over time.

Other causes include:

  • Rapid drying of the concrete: If concrete dries too quickly during the curing process, it’s more prone to cracking.
  • Excess water in the mix: Too much water can weaken the concrete, making it more susceptible to cracking.
  • Heavy loads: Regular pressure from heavy vehicles or equipment can stress the concrete beyond its limits.

Assessing the Damage

Not all cracks are created equal. To determine if a crack is suitable for a DIY repair, start by measuring its width. If it’s as thin as a credit card, you’re in the clear for a straightforward fix. These types of cracks are typically superficial and don’t affect the structural integrity of the concrete.

On the other hand, if the crack is wider, deeper (more than ¼ inch), or shows signs of movement (like widening over time), it’s best to consult a professional. These might indicate more serious issues like foundation problems, especially if accompanied by other signs such as uneven floors inside your home.


It’s also important to monitor the crack over a period of time. If it remains stable, it’s likely a good candidate for DIY repair. However, if you notice changes in width or new cracks forming, this could point to ongoing issues that need professional assessment.

Preparing for Repair

Materials Needed

To effectively repair hairline cracks in your concrete, you’ll need some basic supplies. These are readily available at most hardware stores in Des Moines:

  • Concrete Crack Filler: This is the primary material you’ll use to fill the cracks. There are various types available, so choose one that’s specifically designed for hairline cracks.
  • Mixing Tool: A simple stick or even an old screwdriver can work to mix the filler material.
  • Clean Cloth: Used for cleaning the crack and surrounding area before applying the filler.
  • Water: For mixing with the concrete filler and cleaning.
  • Putty Knife or Spatula: To apply the filler into the cracks.
  • Wire Brush: To remove loose debris and dirt from the crack.

Gather these materials before you start the repair process to ensure a smooth workflow.

Safety First

Safety is crucial when working with concrete and repair materials. Here are some safety tips to keep in mind:

  • Wear Protective Gear: Gloves are essential to protect your hands from rough concrete and chemicals in the filler. Safety goggles will keep out dust and debris.
  • Work in a Ventilated Area: If you’re working in a confined space, ensure it’s well-ventilated to avoid inhaling dust or fumes from the filler.
  • Mind Your Posture: When working on cracks in a driveway or sidewalk, you might be bending or kneeling for a while. Use knee pads for comfort and try to maintain good posture to avoid strain.

Step-by-Step Repair Guide

Cleaning the Crack

The first step is to ensure the crack and surrounding area are clean. Use a wire brush to scrub inside the crack, removing all loose particles and dust. After brushing, wipe the area with a damp cloth to remove any remaining debris. This preparation is crucial for the filler to adhere properly.

Mixing the Filler

Follow the instructions on your concrete filler package to mix it correctly. The consistency you’re aiming for is similar to peanut butter – not too runny, but pliable enough to work into the crack. Add water gradually and mix thoroughly until you reach the desired consistency.

Applying the Filler

Using your putty knife or spatula, apply the filler into the crack. Be sure to press down firmly to ensure the filler penetrates the entire depth of the crack. Overfill the crack slightly, as the filler will settle and compact as it dries.

Finishing Touches

Once the crack is filled, use a damp cloth to smooth out the surface of the filler, blending it into the surrounding concrete. This step will help make the repair less noticeable. Allow the filler to dry according to the manufacturer’s instructions – usually, this takes at least 24 hours. Avoid walking or driving on the repaired area during this time.

Tips for Long-Lasting Results

Proper Curing

Proper curing of the filler is vital for a durable repair. Avoid exposing the repaired crack to water or moisture until it has completely set. This might mean covering the area if rain is expected or avoiding watering nearby plants for a day or two.

Preventive Measures

To minimize the likelihood of future hairline cracks:

  • Seal Your Concrete: Applying a concrete sealant can protect against moisture penetration, temperature changes, and surface wear, all of which can contribute to cracking.
  • Control Joints: If you’re laying new concrete, consider incorporating control joints. These are planned cracks that allow concrete to expand and contract without causing random cracking.
  • Regular Maintenance: Inspect your concrete surfaces regularly for signs of wear and tear. Early detection of minor cracks can prevent them from developing into larger problems.


Congratulations, you’ve just tackled a common home maintenance task and contributed to the longevity of your Des Moines property! By following these steps, you’ve not only repaired unsightly hairline cracks but also learned valuable skills for future DIY home improvements. Remember, regular maintenance and early intervention are key to keeping your concrete surfaces in top shape. We hope this guide has empowered you to take control of minor repairs and maintain the beauty and integrity of your home. Happy DIYing, and remember, a little effort goes a long way in home care!

Get Your No Obligation Free Estimate

Enter your details and one of our advisors will be in contact with you shortly...

Scroll to Top