Do Concrete Countertops Crack?
Miniscule, or what are referred to as hairline cracks, are nearly inevitable in a concrete countertop. They don't always occur, but they can develop. The cracks tend to be non-structural and are a result of the natural shrinkage of the concrete. It's important to understand how and why they occur in order to minimize or prevent them.
Common Cause of Cracks
Jeff Girard of Concrete Countertop Institute provides a great overview of the common causes of cracks. Most cracks are caused by the long-term drying shrinkage of the concrete. These are the most common type which are very small and relatively short. They are of no concern to the structural integrity of the concrete. In fact, more often, they are viewed as inherent characteristics of the concrete and not as flaws.
How to Prevent Cracks
Proper reinforcing when the concrete countertop is poured is the best way to reduce the likelihood of cracks. Out-of-level cabinets, improper supports, improper lifting and installation of the countertop can also contribute to cracks. It is wise to discuss how the countertop will be reinforced with your contractor for reassurance as to how they try to prevent significant cracking.
The possibilities of hairline cracks may be inevitable, but it's certainly not a reason to avoid concrete countertops. With some concrete countertop designs, it is these cracks specifically that are desired for creating a rich, worn-in appeal to the surface. It's realistic to expect the cracks, but, also keep in mind, that any unwanted minor cracks can be repaired and/or disguised.