Concrete Behaving Badly: It's Likely Not Your Fault
You did your research, you interviewed half a dozen contractors, you followed any recommendations and instructions to a T, and now all of a sudden you’re discovering cracks in your concrete slab. Or maybe you’ve been in your home for many years with no issue but now all of a sudden, you notice some cracks and sinking. What is happening and where did you go wrong?! Well, you likely did nothing wrong at all and it’s quite possible the contractor didn’t either. As we like to say here at Chattanooga Floor Care, concrete is a fickle lady! Sometimes you’ll encounter a 30 year old slab with hardly any damage at all, and then a 2 year old slab that looks like it was poured in 1923. We’re going to touch on what causes concrete to behave badly and what steps can be taken to minimize those risks, giving you a long lasting area, whether it’s a patio, porch, garage or any other space. But before we get into that, we’ll talk about the life of concrete.
Many people don’t give much thought to the lifespan of concrete and have a predisposed notion that concrete is forever. Unfortunately, as we’ve pointed out before, nothing lasts forever, but there are things you or the contractor pouring it can do to prolong its life. For starters, there are many types of concrete and they’re intended for different uses, therefore they’re going to behave differently, and making sure you’re using the correct one will play a large part in its lifespan. There’s quick drying as well as concrete that’s intended to be as strong as possible, among others. Other major factors are the environment and the weather that’s typical for your area, especially extreme weather conditions, which can reduce the lifespan of your concrete, though they do make specific mixes for extreme weather. The life of concrete is a miracle in itself when you break down the process. It is typically mixed off site, then put into a truck, transported however many miles, then poured and asked to bear the weight of equipment on it, and it could be dealt with by a dozen others before you ever lay eyes on it. Even with all of that, experts suggest you can expect anywhere from 50 to 100 years out of your concrete, depending on the environment and how well it’s taken care of.
So how do you take care of it and prolong its life? The usual; feed it, make sure it has a warm place to go at night. Ok, that’s not quite accurate, however there are a few different actual tips on this, including but not limited to: cleaning the surface properly and on a regular schedule, minimizing water exposure if possible, sealing it periodically, limiting weight loads and repairing any cracks if they do arise. While these are all steps to take after you have your slab, there are also some things to consider prior to the pour that will play a part in the longevity of your concrete. For example, does your intended patio site sit at the base of a hill where rainwater will always roll down into it? Do you have a large tree nearby that could cause future issues, with the concrete raising due to roots? The surrounding areas will impact the life of your concrete as much as the way it’s cared for. But what else causes cracks, sinking, rising, etc.?
The most common reason for cracks we encounter is expansion. Sometimes concrete will have saw cuts to help with this problem, but that’s not always the case, and even then some slabs with saw cuts will still experience factors resulting in cracking or erosion. Much like a balloon, heat, such as a dry and warm spell during summer, will cause expansion. During expansion, concrete will push against anything in the way, like a wall or other slab, and if neither has the ability to flex, the force can be enough to cause a crack. Heaving occurs when the ground freezes, and as we know, freezing causes expansion. Tree roots also largely contribute to heaving, a potential problem mentioned above, because as the tree grows, so do the roots, pushing up too far and compromising your slab. Settling is also a common factor, occurring when a void is created in the ground below the surface of the concrete. Something that can lead to settling is water run off. If you have drainage near your concrete, or your concrete sits near a hill where water will pool, that water has to go somewhere, sometimes unfortunately being under your slab. Over time this washes out the dirt, creating the void or hollow space, resulting in no support under sections of your slab.
Photo by Windler Foundation Repair via https://www.windlerfoundationrepair.com/polyjacking/
We hope that we have provided some insight on what to expect when you’re expecting … a concrete slab. We want our clients and non-clients alike to feel confident and knowledgeable about how to best take care of their existing spaces as well as have some ideas on how to make sure they’re doing any future concrete slabs justice with proper placement and care. With said proper placement and care, you should expect to enjoy your area for many years to come and hopefully, someday, we can help you spruce up that area and turn it into a UV, stain and slip resistant work of art. And hey, If you happen to be in the market for a concrete coatings contractor, or any contractor really, check out one of our past blogs, A Guide to Choosing Your Concrete Flooring Contractor, for tips and tricks to make sure you’re finding the right contractor for your project.
“6 Types of Concrete Cracks and What They Mean.” Concrete Supply Co., 11 Feb. 2019, concretesupplyco.com/6-concrete-cracks/.
Weaver, James. “What Is the Lifespan of Concrete?” Razorback Concrete, 20 Aug. 2020, razorbackconcrete.com/what-is-the-lifespan-of-concrete/.
Admin. “7 Necessities for Maximizing Concrete Lifespan.” Capital Concrete Cutting Inc, 3 Jan. 2020, www.capitalconcretecuttinginc.com/7-necessities-for-maximizing-concrete-lifespan.