While concrete cracks can look harmless, they can easily widen and lead to further damage like chips and flaking. This deterioration of the concrete surface can eventually make a larger, more costly replacement project necessary. Luckily, fixing small cracks is very easy for homeowners, and there are many great concrete crack repair products on the market!
Concrete is one of the most durable building materials available, ideal for both skyscrapers and backyard patios. When it’s mixed well and given time to properly cure, concrete can ably resist cracking for a long time. But if the proportions of ingredients are off, the concrete isn’t allowed to cure for the right amount of time, or it’s standing up to weather, cracks can start appearing on the surface.
The Best Concrete Crack Repair Solutions: Polyurethanes and Epoxies
For deep cracks, a polyurethane (also known as a polymer) product is the best choice. This is an elastomeric, fast-setting foam that is ideal for applications that involve crack sealing for waterproofing. Polyurethanes can handle slight concrete movement, helping the seal stay intact. They also work quickly, hardening and foaming minutes after you inject them into the crack; this reduces the likelihood of the material running out of a crack while it’s still in a liquid form. However, they don’t have the same strength as epoxy crack fillers, and shouldn’t use them for structural repair.
One of the most highly rated polymer repair solutions is SAKRETE Concrete Crack Filler. It can fill and seal cracks in concrete that are up to 1/2 an inch (13 mm) wide by 1/4 of an inch (6 mm) deep. It’s great for preventing water intrusion that can lead to further concrete degradation.
For cracks that affect structural integrity, choose epoxy crack repair. They take hours to cure and harden, which gives the epoxy time to flow into even the smallest nooks and crannies. Unlike polyurethane, the epoxy can flow out of the backside of the crack before it can harden; this is especially difficult if there’s backfill outside the wall that has separated from the foundation.
Epoxies come in a range of viscosities, from super thin to paste, and this thickness depends on the width of the crack and conditions. One of the best epoxies is Epoxyshield Concrete Patch; it’s easy to mix, permanently sticks to the concrete, and won’t stick. Like all good epoxies, it has a much higher PSI than concrete, and Epoxyshield is thick, which is ideal for wide cracks.
What Causes Cracks?
Cracks in concrete are quite normal following the installation. Many cracks form if the concrete dries too quickly, causing it to shrink. As well, if the mix has an excess of water, it can have considerably less strength. Too much water also results in shrinkage, which in turn can lead to cracks.
However, when the crack is part of outdoor concrete, it is at the mercy of precipitation and fluctuating temperatures. The type and location of the crack can determine what type of repair product you need, as they vary in viscosity and repair thicknesses. Even cracks in a sensitive area like the foundation may only require a DIY concrete repair solution!