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Cracked Foundation Slab

Cracked foundation slabs are some of the most frustrating generalized structural problems out there. How can you fix it more effectively?

Large crack in concrete close up with tape measure

Best Practices for Fixing Cracked Foundation Slabs

A cracked foundation slab can lead to very serious problems over time. Whether it starts out as tiny hairline cracks or it exposes itself as a giant chasm in your foundation, a cracked foundation slab is a serious concern. It’s important to consider how you can fix that cracked foundation slab.

However, it’s important that you know exactly what you can do to fix these slabs. When you’re considering fixes for a cracked foundation slab, you may first want to get some background on it. Here’s everything you need to know about cracked foundation slabs.

Fixing Cracked Foundation Slabs Early

The best way to make sure you don’t have significant foundation concerns in the future is to fix cracks in your foundation slab as early as possible. Here’s how you can fix these slab cracks early on in the process.

  • Pay Attention to Warning Signs

Your first step should always be to do your best to pay attention to the warning signs. Foundation failure doesn’t come without other signs. There are a number of potential signs you may experience before you start seeing very serious foundation failure issues, including:

  • Bowing walls
  • Basement moisture
  • High indoor humidity
  • Uneven floors
  • Bouncy floor joists
  • Gaps in walls and doors

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This is by no means an exhaustive list. However, it can at least showcase the fact that cracked foundation slabs don’t come around without other signs. There are a number of symptoms you’ll experience before your foundation slab is unsalvageable. If you keep your eyes open, you’ll be more likely to catch things early.

  • Partake in Yearly Examinations 

It’s important that you bring in an expert crew to do an examination of your home’s structure every year. This is even important when it doesn’t seem like your home has any issues. When you bring in a team of experts to do an examination of your home’s structure, even though it seems like it’s healthy right now, you’re more likely to notice things that could easily turn into serious problems in the future.

Fixing a problem early is almost always easier and less expensive than fixing a problem once it really becomes obvious. When you bring in a team for a yearly examination, most of the time they’ll look through your structure and find no issues. However, every so often they may let you know they’ve found the beginnings of a problem. That’s when you’ll be glad you maintained your examination schedule.

  • Understand Where Foundation Slabs May Crack Most Frequently 

It’s also important that you know what to look for on your own. Many basements have a foundation slab visible, which means that especially if you use your basement purely for storage, you might actually see your slab every day. If this is the case, it’s vital that you pay attention to your basement foundation slab. Just knowing the basics can help you catch problems earlier.

Even with a yearly examination, remember that these experts will only see your home once a year. You see your home every day. You need to be looking for potential problems that may occur on your own. That way, if you start seeing warning signs of a problem, you may be able to notify an expert to come in earlier than your yearly examination.

Will the Problem Stop with the Foundation Slab?

Some homeowners wonder whether these problems will actually have a measured impact on the rest of the home. Not only will your cracked foundation slab have a significant impact on your foundation, but it will impact the home as a whole, including these areas.

  • Basement 

The basement is likely the most obvious area where you may start experiencing problems. That’s largely because a foundation slab typically lies underneath the basement. When your foundation slab starts having issues, it could seriously impact the basement. At the very least, the basement is most likely to be the first area that takes damage.

You may notice a number of basement-specific problems because of your foundation slab cracks. For example, you might notice more issues with basement waterproofing. Water often comes up from underneath the basement, and if you have a slab crack, water can come in much more easily. You can also notice basement wall bowing and general basement humidity, mold, and mildew.

  • Inside the Home 
Wall and Floor Gap Close-up with laser level

The rest of your home will also have issues related to the foundation slab cracks. Typically, a foundation slab cracks for a reason. It doesn’t just crack randomly. That means whatever caused your foundation slab to crack will have an impact on the rest of your home. It doesn’t have to happen directly because of the foundation slab crack for it to have a correlation.

For example, if your foundation slab cracked because of expansive soil, you could have expansive soil problems throughout your home. That can lead to a cracked chimney, gaps between the walls and floor, and tilting floors. It’s always important to look at the base reason for your foundation slab cracks so you can tackle that problem in the rest of the home.

  • Outside the Home 

These problems don’t just stop when they’re inside your home. As a matter of fact, there are plenty of foundation problems that can be pervasive throughout the entire property, not just the home that the foundation is on. Again, you have to look at the problem that caused the crack in the foundation slab, not just the crack itself.

Most commonly, these problems will come through with some issues regarding your concrete. Concrete is a part of your home from front to back. For example, you may have concrete in your driveway, sidewalks, patio, pool deck, and more. If you’re seeing a crack in your home’s foundation slab, it’s a good idea to look at the other concrete in and around your home as well.

FAQs About Cracked Slab Foundations

One thing many homeowners wonder about is whether they might be able to fix their concrete problems by themselves. Is it possible to fix the cracked foundation slab by yourself? Here’s what you need to think about before you try to fix the problem on your own. 

  •  Concrete Patches

The first option that many homeowners consider from big box stores is a concrete patch. For a concrete patch, you typically mix a very small amount of concrete, then apply it over the crack. It sets and supposedly keeps the concrete from cracking again. However, the problem is that you haven’t actually fixed the problem; you’ve just put a bandage over what you can see.

  •  Fixing the Underlying Problems

It’s much more important that you fix the underlying problems than that you make your foundation cracks look good. Fixing the underlying problems in your concrete will help ensure that you don’t end up with serious problems down the line. Plus, a concrete patch may crack if you don’t fix the problems that caused the crack.

If you’re looking to make sure that you’re handling cracks appropriately, you might wonder if a crack needs to get worse before you have to think about it. For the most part, it’s a good idea to tackle all cracks as early as possible, although there may be some exceptions.

  • Hairline Cracks

Hairline cracks might not need a fix as soon as you notice them. A hairline crack typically has to be small enough that you can’t fit a business card into it, which typically indicates cracks less than one-sixteenth of an inch in width. These cracks don’t necessarily need fixing, but if they’re any larger than that, they might.

  •  Any Other Cracks

Any cracks that are larger than a hairline crack could be indicative of a serious problem. If you can put a business card into a crack, it’s very likely that the crack isn’t just surface-level; it’s almost certainly a serious problem that stretches deeper into the concrete. These cracks need fixing as early as possible.

At some point, you may have heard that a concrete slab foundation will often crack. This may have come from someone who had cracking problems with the concrete slab foundation and didn’t know how to prevent it. Understanding cracks in a slab foundation can be beneficial to ensuring you invest in the right response for your slab foundation.

  • Early Hairline Cracks

One thing that may occur in a concrete slab foundation is that you might notice hairline cracks forming in the first few months after pouring the concrete. Because the concrete will continue to shift and shrink very slightly as the months go by, it’s possible for you to experience hairline cracks within about the first year after pouring.

  • Cracks Long After the Pouring Process

However, if you start to notice cracks that are forming long after the pouring process is complete, it’s likely there’s something wrong. This is one reason it’s a good idea to do regular inspections of your concrete. Even if the cracks are only hairline, it’s a good idea to take a look at potential underlying causes if you notice hairline cracks out of nowhere.

  •  Bigger Cracks

Pretty much all larger cracks are a problem. If you notice any cracks that are larger than a business card’s width, it’s a good idea to call in an expert. It’s likely that these cracks are coming from an underlying cause, like foundation shifting, and you may need to tackle those underlying causes.

Some people worry about their foundation fixes because they think they’ll have to repour the foundation entirely. Repouring typically isn’t the best option for foundation fixes, however. Here are a few of the ways that you can fix your cracked foundation without repouring.

  •  Polyurethane Foam Injections 

If the main problem is that your foundation is sinking, polyurethane foam injections may be a great option for you to lift the foundation effectively. This is one method of lifting concrete, and it’s incredibly effective if you have erosion problems underneath the concrete slab. It can also help you fix the cracks in the foundation if they’re due to a sinking foundation.

  • Structural Supports

Added structural support may also help your cracked foundation. If your foundation is sinking into the ground because there’s not enough structural stability available for the foundation, you may need to increase it. Your structural options include things like helical piers and push piers, which shift the weight to the bedrock layer of the soil.

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Fixing Your Cracked Slab Foundation with the Best Approach

At the end of the day, there are a few methods of fixing a concrete slab foundation. However, you may not have the ability to know exactly which method of fixing the foundation is the best for your home. That’s because most home problems require a pretty substantial amount of knowledge.

Your best option will always be to talk to an expert about these problems. If you request more information from a Groundworks expert, they’ll give you insights you won’t be able to get on your own. Regardless of the size, shape, or potential danger of these cracks, a foundation repair expert will be able to give you the maximum amount of information.

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