An uneven concrete slab can be an incredibly frustrating thing to deal with. Whether you’re experiencing multiple slabs that no longer match up correctly or a single slab that’s sinking in the middle, it’s annoying to see an integral part of your home start to look different.
Of course, annoyance isn’t where this ends. It can also be a safety hazard. That’s exactly why so many people look into how to repair uneven concrete when they start to see an uneven slab foundation under their home.
As a homeowner, you might not know a lot about concrete slabs and your concrete foundation. This can make it more difficult for you to make the decision to repair it. With this guide, you’ll get more information about uneven concrete repair.
Concrete Slab Repair FAQs
Learn more about concrete slab repair
Before looking at the reasons to repair your uneven concrete slab, you should probably first understand what causes it. That way, you’ll know what the various repair possibilities are that can help your concrete slab rise back up.
There are three very common reasons to encounter an uneven concrete slab.
By far the most common reason for an uneven slab foundation is house settling. It’s common for homes to experience some amount of settling through the years, and as the home settles, it might settle slightly differently in different areas.
If there’s a concrete slab or multiple concrete slabs on and around your home, that settling will start to show up in a very obvious way. The slabs might not match up, because they’re settling differently. If it’s settling too much, that will become even more apparent.
This is one way that house settling happens. Freeze-thaw cycling describes the way the ground outside freezes, then thaws depending on the temperature outside. In home repair terms, that means when the ground freezes, it expands or swells upwards (frost heaving), and when it thaws, it compacts.
This expanding and contracting isn’t great for a home. You can see the same thing happen with water and droughts, which also causes the soil to expand and contract. If this happens underneath a concrete slab, it’s easy for the slab to raise or lower.
You might also experience an uneven concrete slab if the original construction crew utilized poor planning when laying that concrete. Did the construction crew mix the concrete properly? Did the designer construct the foundation so it all bears the weight equally?
Though this is the least common reason for uneven concrete, it’s still an important one to pay attention to. Poor planning can impact a substantial amount of your home. If the original construction crew and designers didn’t plan the home properly, you need to know that for the rest of the structure.
Some homeowners want to put off this repair for another day. This is especially common among new homeowners who don’t have a lot of experience with home repair and don’t want to spend a lot of money on something that doesn’t seem like a huge problem.
The thing is, uneven concrete repair is more important than you might think. Consider these top seven reasons to repair your uneven concrete as soon as possible.
1. Worsening Problems
This point is very simple: you’re never going to have concrete that’s more intact than it is right now. The concrete you’re talking about will only deteriorate further, potentially leading you to repairs that are more expensive and more invasive. Sure, you’re not paying money for it right now, but does that really matter when you’ll pay more later?
At a certain point, you can’t do anything except fully replace the concrete. You can perform repairs on the concrete if you handle the uneven concrete repair early. It’ll be less expensive, less invasive and more effective if you fix the problems as quickly as possible. No one wants to spend more money than necessary on a home fix, but that means fixing the problem right now.
2. Individual Safety
You might not recognize it yet, but uneven concrete slabs are dangerous. When you have multiple uneven concrete slabs across a surface, they pose a tripping hazard, which is worsened for people who have balance issues. A sagging concrete slab can also pose a tripping hazard because the brain isn’t fully prepared for the slant the concrete provides.
Repairing the uneven concrete slab problems you have is the best choice for your family. This is especially true if it’s concrete on the exterior of your home, such as your driveway, but you should maintain the safety of your home on the inside as well. Any uneven concrete slabs pose problems for your family, so it’s always important to fix it.
3. Pooling Water
Uneven concrete slabs create opportunities for pooling water across the slab. Water can pool in cracks in the concrete, underneath the concrete if there’s been soil erosion, and in between concrete slabs that have sunken to different heights. During cold weather, this water can also freeze, causing additional safety hazards.
When water freezes, it expands. That means if water gets into very small cracks in these uneven concrete slabs, then freezes, it’ll expand those tiny cracks, making them much bigger cracks. This echoes the first point: the earlier you fix the problem, the less likely you’ll be to have bigger problems down the line.
4. Water Intrusion
This is an especially significant problem if you’re dealing with a concrete slab in your home that lays directly on top of the soil. Think about what happens if the uneven concrete slab moves to such an extent that it allows open access to the soil from the home. If that happens, there’s a very simple way for water to get into your home.
Whether it’s from hydrostatic pressure, humidity, condensation or anything else, water really wants to get into your home. Your protection against that water pressure is extremely important because it allows you to keep yourself safe from water damage. Fixing your uneven slab foundation is a good first start to avoid water damage.
5. Curb Appeal
Sunken concrete slabs are simply eyesores. As a homeowner, you probably want to do your best to have a visually pleasing home. After all, that’s why many people put a lot of time, money, and effort into things like maintaining a lawn, painting the home and making sure the backyard stays nice. Do you want to toss that curb appeal because of an uneven concrete slab?
Sure, this might not be the most important point on the list, but it’s still one you should think about. This is especially true if you tend to take a lot of pride in the way your home looks. Concrete repair is easier than you might think it would be. Invest a bit of time and money into repairing the uneven concrete and you’ll be pleased with how the whole structure looks again.
6. Resale Value
When you’re placing your home on the market, potential homebuyers will dissect your home very critically, and so will any home inspectors they hire. They’re looking for things to lower their offer to buy. You don’t want to give potential home buyers any reason to pass over your home or make a lowball offer, and having sunken concrete is one of the things that will give them that reason.
You might not be thinking about selling your home right now, so this thought might not cross your mind. However, unless you’re planning to live in this home for the rest of your life, you’re probably going to sell the home eventually. That means you always want to think at least a little bit about the resale value of every move you make.
7. Structural Damages
This is possibly the most important reason you should consider uneven concrete repair as soon as possible. Even if you think your home’s doing fine right now, it’s important to realize that everything in your home influences other things in your home as well.
Think about it. As the concrete settles, so does everything above it. When the concrete slab foundation starts to crack and settle, that’ll cause serious damage to the rest of the home above and around it. The rest of the home will start to crack and settle as well.
Uneven concrete slabs that you don’t fix can cause lasting structural impacts. You might start to see windows binding, doors sticking, floors sinking and more. Plus, that sinking concrete may be indicating some other structural impact you should pay attention to. This is a convincing argument for fixing sunken concrete as soon as possible, no matter where it is in your home.
You have a few options when you’re trying to determine how to repair uneven concrete. These options work differently for different people. That means depending on your individual situation, you may need something different. When you contact JES, an expert can tell you the best solution for you and your home.
What can you do to lift your uneven slab? These are the three most common methods of uneven concrete repair.
Pressure grouting, also called mudjacking and slabjacking, is the most traditional method of lifting a sunken slab of concrete. With this method, the construction crew mixes a slurry of concrete and filler material, traditionally mud, and then they inject it underneath the uneven concrete through soda can-sized holes that they have drilled.
As you can probably imagine, this is a very invasive and difficult method of supporting concrete slabs. It can take up to two weeks for the slurry mixture to cure, during which you can’t walk or drive on it. Plus, it doesn’t always raise the entire slab and tends to have a hard time raising the edges. Because of these difficulties, JES doesn’t recommend it for residential homes.
If your uneven concrete has deteriorated to the point where there are significant cracks in the surface, you might have no choice but to opt for concrete replacement. With this method, an expert removes the existing concrete and pours it again from the beginning.
This is also not ideal. In some areas, if the concrete supports a significant amount of weight, the process may need to move forward very slowly, and it can be expensive to accomplish. If you’re able to fix the problem before those cracks form, you can avoid the frustration of concrete replacement.
Polyurethane Foam Injection
Polyurethane foam injection is a unique method of uneven concrete repair. That’s because it’s a very lightweight mixture that gets pumped underneath the concrete through penny-sized holes. Once inside, it expands up to 25-35 times its original size, then cures in around 15 minutes. It’s also lightweight, weighing around 5% of what pressure grouting slurry does.
This is the method that JES prefers to use for uneven concrete repair. It’s quicker, easier and less invasive than pressure grouting, and it’s much more accessible than full concrete replacement. Plus, it’s time-tested. Even the Department of Transportation has trusted it for more than 30 years, using it for roads and other concrete structures.
A concrete foundation can be great in some instances, but it can also come with its fair share of problems. Concrete foundations are especially prone to uneven foundation settling as well as basement floor cracks. These concrete foundation defects are important to look for and address as soon as possible for maximum benefit. Similarly, sinking concrete elsewhere on your property also is a common problem.
The easiest way to see whether your foundation is cracked is to perform your own inspections regularly. Many homeowners can simply go into their basement and take a look at the foundation or walk around the outside of the home and look for cracks. However, if you don’t have the ability to look at your own foundation, you may want to schedule an inspection to do so.
Typically, any cracks in your concrete foundation are a bad sign and can signal that you’re having foundation problems. However, the one type of crack that might not be a bad sign is a hairline fracture that occurs a few months after pouring the concrete; these are usually settling cracks in new construction.
Talk to a JES Expert to Learn More About Your Options Today
If you have an uneven slab foundation, you’re going to need to understand uneven concrete repair. The only real question is when you’re going to do it. If you choose to repair your uneven concrete slab or uneven slab foundation right now, you can save money and have access to a better option.
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