Water is enemy number one for concrete. Too much water can wash away the soil supporting your concrete. Too little and it can cause the soil to shrink. And when water freezes and thaws over and over and over and over again, it can cause the surface of your concrete driveway to crack, pit, and crumble.
Small cracks here and there that are narrower than ¼ inch are most likely the result of shrinkage as the driveway cured. Like spider web cracks, these small cracks do not indicate a larger problem, and they often show up soon after the concrete is poured.
Evaluating Concrete Crack Severity
Cracks smaller than 0.3 mm in width are generally not serious and of not structural impact. However, they should be monitored for any growth. Cracks of greater width than 0.3 mm may present structural durability issues.
It is possible the base under your driveway wasn't compacted correctly, and that may have caused the concrete to sink or settle slightly, and thus to crack. Or some water may have run under the slab and eroded or consolidated the base to the point where the concrete was not supported.
While you may see small driveway cracks as nothing important, they can be the first sign that you may have foundation issues.
When concrete dries and shrinks, cracking can occur hours after being poured. Any crack that is ⅛ of an inch or smaller on your patio or driveway is considered standard. Some hairline cracks may form and disappear after a month or two.
Shrinkage: The most common type of cracking in concrete, especially early on, is shrinkage. Concrete is a mix of cement and water. As the concrete hardens, which is caused by the cement and water forming bonds, some of that water escapes through evaporation.
They are a natural part of concrete curing and getting hard. There are very good repair options to keep cracks from getting worse, but no good method for making them go away.
Here are some potential problems if a crack gets wide enough for water to seep into the slab: Water can rust your rebar, causing serious damage to your concrete. Rusting/cracking weakens the foundation.
Deep cracks or cracks over 1/4-inch wide usually signal more serious problems. While they can be filled, the fix is often temporary. Uneven cracks bigger than an inch wide occur more often in older driveways than in newer ones and almost always indicate underlying structural issues.
The older your asphalt is, the more likely it is to develop cracks. As it gets further along, the material begins to degrade and loses its natural ability to withstand your surface's daily pressures. So when that significant rainfall or that freeze and thaw cycle comes, older driveways are more likely to suffer damage.
Uneven drying, shrinkage and temperature changes can all cause fractures in your slab. To avoid water seepage and further damage, it's critical to seal any cracks that develop.
Poured correctly and well-maintained, asphalt pavement can last for nearly 20 years. However, it still requires steady maintenance over time. A driveway should be resealed about every 3 years and often, asphalt driveway cracks develop and need to be repaired more frequently than that.
Cracks in your concrete driveway or other concrete surfaces might not look good, but often they aren't cause for concern. However, there are cracks that should be dealt with as they can become a problem in the future.
The hardening, or curing, continues as long as moisture remains in the concrete. If too much water is lost from the concrete through evaporation, the hardening process slows down or ceases.
Thermal cracking occurs due to excessive temperature dif- ferences within a concrete structure or its surroundings. The temperature difference causes the cooler portion to con- tract more than the warmer portion, which restrains the con- traction.
Epoxy sealers like Rust-Oleum Concrete Patch & Repair are waterproof products that are extremely strong and durable. These are good for cracks in foundation or basement walls, as well as horizontal cracks on concrete pavement or driveways.
A sealed concrete driveway can last much longer than an unsealed carport. Although a driveway that hasn't been sealed takes time to breakdown, its deterioration is inevitable. The primary reason concrete doesn't last as long without sealer is that it's a porous material.
Without a high-quality sealer, the beautiful decorative work you've had done on your driveway is at risk of getting damaged, fading, and looking worn out in a short amount of time.
According to HomeAdvisor, a driveway repair professional will charge as little as $300 to fix minor concrete driveway cracks, but most homeowners can do the job on their own with a rubber or synthetic crack filler. This costs about $0.10 to $0.15 per linear foot—but watch out if cracks are larger than 1/8 of an inch.
Can you pour concrete over cracked concrete? Pouring concrete over cracked concrete before at least repairing the cracks is not going to go well. If the issues that caused the cracking to occur on your existing concrete surface are still present, they will affect your new concrete surface, too.
A penetrating primer is applied to the concrete to strengthen the surface and increase the bond strength of the repair. Epoxy putty or elastomer is applied into the crack to create a smooth surface. A bond-breaker, life Teflon tape, is applied over the crack to allow for movement.