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Slab Foundation Cracks

Slab foundation cracks can be a serious problem that you need to address as soon as possible. What should you know about these cracks?

Crack in slab foundation

Slab Foundation Cracks & How They Impact Concrete Lifting

Slab foundation cracks are one of the most frustrating problems you can discover. This is partially because slab foundation cracks tend to be a problem that many homeowners assume is common in a foundation.

That means you might have secondary issues with your slab foundation that you don’t even know are happening due to these cracks. If you’re looking to learn more about slab foundation cracks, here’s what you should know.

Why Do Slab Foundation Cracks Occur?

Many homeowners don’t even know why slab foundation cracks occur in the first place. It’s common for slab foundation cracks to be part of your home for several reasons. Here’s what you need to know about the reasons for slab foundation cracks.

  • House Settling

One major problem that can occur in your home is when things settle more than they should. Some amount of home settling is common, especially in the first few years of the home’s existence. However, it shouldn’t settle too much. It also shouldn’t settle unevenly, or else there may be a variety of problems in and under the home.

When the home settles a dramatic amount, many problems might occur its foundation and beyond. One problem that may occur is a slab foundation crack that can cause a variety of issues throughout the home. It’s especially common if you have too much weight on one side of the slab and not enough on the other.

  • Expansive Soil 

Expansive soils are one of the most annoying things you can have around your home. Expansive soil is one that expands more than usual when water enters it. Clay soils are more likely to be expansive soils, which means if you have clay in the soil mixture around your home, you’re more likely to end up with serious soil problems.

The expansive soil problems can also lead to slab foundation cracks if you have expansive soils around the slab foundation. Because expansive soils can expand up to 15 times their initial size, if they are located underneath a slab foundation, they could expand up onto it, cracking it in multiple places.

  • Excess Water 

Even if you don’t have expansive soil, water in and around the home foundation is an important thing to pay attention to. Handling your home’s hydrostatic pressure, which is the weight that water exerts when it’s at rest, is an important element of maintaining your home’s health and well-being. You need to avoid excess water around your foundation at all costs.

Because water weighs around 62 pounds per cubic foot, even a small amount of water around the home’s foundation can have a serious impact on the home’s structural stability. If you have enough weight pushing against the foundation, you may end up with cracks in your slab foundation and cracks in the foundation walls.

Causes For Common Concrete Problems

What Do Slab Foundation Cracks Do to a Home?

Some homeowners choose not to fix their slab foundation cracks because they’re under the impression that the cracks won’t have much impact on the rest of the home. Here are just a few of the ways slab foundation cracks can impact your home as a whole.

  • An Entrance for Water 

One of the benefits of slab foundations is the fact that it’s intrinsically waterproof. You don’t have to worry about water coming up through the slab foundation when it’s just a slab of concrete. However, you do have to worry about water coming up through the foundation if you have a crack that stretches through the entirety of the foundation.

Water is great at finding its way into just about anything, and that means if there’s a way to allow water into the crawl space or basement, water is probably going to find its way inside. Even a very small crack that allows a tiny amount of water inside can develop into a much more serious concern, even creating standing water in the crawl space or basement in significant cases.

  • Foundation Heaving and General Soil Problems 

When you have slab foundation cracks, there’s a good chance you could have those cracks because of issues with foundation heaving. Foundation heaving occurs when water and soil move from the edges of the home’s foundation toward the center of the foundation, causing it to move upward and create serious foundation concerns.

Whenever you’re having issues with the soil underneath your home’s foundation, you need to look at what those problems might end up leading to. Soil problems, especially soil washout, can cause a whole host of additional problems, including but not limited to generalized issues with the home, sticking doors and windows, and much more.

  • Issues with Structural Concerns

Structural problems are one of the many issues you might run into because of slab cracks. That’s because slab cracks in and of themselves cause your foundation slab to be less structurally sound than it might be otherwise. With cracks, the foundation slab will tend to be more prone to issues with moving and settling because the slab is no longer one uninterrupted piece of concrete.

These structural concerns can be even more worrying if they’re the reason you have the concrete slab cracks in the first place. For example, if your concrete slab started to crack because you didn’t have enough support on one side of the slab, it’s much more possible for the concrete to start to sink into that end now.

FAQs About Slab Foundation Cracks

The good news is that slab foundation cracks are a problem that most foundation repair experts know all about. This is a common problem, so experts can manage the situation whether it’s the early stages that need simple fixes or the late stages that need emergency measures. Here’s why you should tap into the knowledge of a foundation repair expert.

  • Reasons to Trust an Expert

When you choose a foundation repair expert, you’re paying for experience and knowledge. To a layman’s eye, it’s easy to misdiagnose harmless hairline cracks with real fissures that will cause damage. Likewise, you won’t be able to spot when the crack is an isolated problem or when it suggests an underlying issue. 

A foundation repair expert can come out to your home, assess your property, the foundation, and its cracks, and make suggestions. They can also troubleshoot other symptoms that may be cropping up around your home and take a look at how your landscape, soil type, and even the design of your home may be contributing to the problem. Not only does this allow the expert to suggest the right gear to install or sealants to use when making repairs, they can also suggest changes to your landscape or reinforcement gear for your walls that might prevent issues from developing in the future. 

  • An Expert’s Process

To get help with your cracked slab foundation, you can first get in contact with a foundation repair expert for a free quote. Once it’s scheduled, they will come to your home and inspect the area. This can take only a few minutes or up to an hour. During this time, they can point out warning signs, help diagnose problems, and then compile a list of solutions. 

The expert can then review the plan with you, so you’re up to speed on the situation and the options you have going forward. Pricing may vary depending on how severe the damage is and the gear needed to repair the foundation. However, you can learn what the costs are upfront and better understand the amount of time needed. Experts will help you make an informed decision and if you agree to the plan, the professionals can get to work.

In most situations, you can fix your slab foundation without having to repour the entire thing. However, it is possible to end up with a slab foundation that’s cracked beyond repair. In this case, a complete repour will be necessary. Here’s what you should know about this worst-case scenario.

  • Repouring the Foundation

This nightmare is more likely to occur if you ignore the early warning signs. Hairline cracks that are too small for a business card to slot into may be fine. However, larger cracks or those which stretch for several feet are worthy of your concern. These should be addressed by a professional, especially when it’s in your foundation because it supports the entire weight of your home. 

If you avoid dealing with your slab foundation cracks for long enough, you can certainly end up with too much damage. Filling in cracks will only buy you a little time and the foundation may need to be entirely repoured eventually. This is invasive and frustrating, but it typically only happens if you’ve genuinely avoided managing the slab foundation for a long time.

  • The Benefit of Calling in an Expert

Any damage to your foundation must be handled by an expert. With DIY fixes, you can always make a mistake or use an ineffective solution. A cracked slab foundation may cause the walls, support beams, and your roof to sag, crack, or even collapse. If your foundation needs to be repoured, you will need to contact a local expert. 

The good news is, contacting an expert can also help you avoid this entire problem. It takes a long time for your foundation to become this unhealthy. So long as you call in a foundation repair expert when you first start noticing problems with your slab foundation, they can catch the early warning signs, recommend ways to fix the existing damage, and suggest ways to preserve the foundation going forward.

Homeowners may worry that a slab foundation is more prone to cracking. Like other home repair rumors, the truth is much more complicated. 

  • More Openings for Weak Points

Slab foundations can be more prone to cracks, but that’s not because they’re concrete. It’s because they’re generally made up of just one slab. While this does create a uniform layer that’s smooth and durable, it also opens up the door for structural weaknesses over time. That’s especially true if any errors were made during the pouring stage. 

For example, a brick foundation may be made up of several smaller parts that can have gaps. However, one damaged brick will be isolated in a sea of other, stronger bricks. With a slab foundation, if damage is caused to one area, then the rest of the slab is responsible for compensating. If it’s unable to do so, or you don’t correct the problem right away, then you may find cracks spreading throughout the entire slab. 

  • The Strength of a Slab Foundation

The biggest thing to remember is that slab foundations are only strong if they’re properly cared for. Concrete can take an impressive amount of hardship, but once a weak point is found and exploited, the entire thing may crumble. Mistreatment or outside damage can make an otherwise perfect foundation suddenly vulnerable.

Because of this, weak points must be identified and fixed. This will include patching cracks and installing supports to fill in any gaps in the soil beneath the foundation, should they develop. An expert can provide these fixes, but unless you schedule routine inspections, it’ll be up to you to spot these problems.

If there’s a crack in your slab foundation, you might wonder when the best time will be to manage that crack. The answer is: as soon as possible, but especially within the first week. That’s because there are advantages to addressing it early and dangers to waiting.

  •  Handle the Problem Early On

No matter what foundation problems you’re dealing with, from slab foundation cracks to soil washout and anything else, you should always try to tackle the problem as early on as possible. When you handle the problem early on, you’re more likely to mitigate it rather than having to repour the entire slab.

Within the first couple of days, the crack will remain stable. Unless there are sudden weather changes or heavy impact on the slab, the crack shouldn’t get impressively worse. This gives you a short amount of time to contact an expert for repairs. At this point, sealing the crack will take less time and cost far less than if you wait. 

  • The Issues with Waiting 

The biggest issue that can arise if you wait is that the problem will get worse. In the following days, but especially after a week or two, the crack will begin to expand. It may grow deeper or wider, and it may create spider-webbed cracks throughout the slab. If you’re lucky, and if the underlying cause of this is slow-moving, then it may take a month or two for this to happen. 

Slab foundation cracks cause all sorts of secondary and tertiary problems. Handling the situation early on allows you to minimize the number of extra issues. For example, bigger cracks are harder to seal, take longer to work on, and may not bond with any sealants or fillings. Because of this, if you wait, you may need to repour the entire slab, which is costly and time-consuming.

Fix Your Slab Foundation Problems with the Help of an Expert

Slab foundation problems come in many different shapes and sizes. Just because two homeowners have the same symptoms of a slab foundation problem doesn’t necessarily mean that they will end up needing the same fix. The only way you can actively fix your slab foundation cracks is to make sure you’re getting the help of a foundation repair expert.

You can get in contact for a free quote and receive personalized suggestions on how to best safeguard your home, both now and for the future. With a quality guarantee on all work, Groundworks can give you peace of mind and a safer home.

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Disclaimer: “Concrete leveling” means the process by which cracked, uneven concrete is stabilized, and in many cases lifted, by means of PolyRenewal™ polyurethane foam. Groundworks does not guarantee that PolyRenewal™ can make your concrete perfectly level.