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Lifting concrete installation

Interior Floor Slab Lifting

Concrete slab floors are affected by the same forces and problems as other concrete structures in and around your home. Learn how you can restore and protect them with expert help. 

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Interior slab and concrete flooring can be incredibly beautiful and durable, but when it begins to crack, sag, or become uneven, it can quickly become dangerous. As well as being unsightly, depressions in your concrete floor are a tripping hazard. That is why it is important to quickly address the cause of this damage and lift the flooring out once more. 

Repairing Sunken Interior Slabs

There are many potential solutions to depressions in your concrete flooring or uneven concrete slabs. These solutions range from incredibly invasive to minimally disruptive. The solutions that most foundation repair specialists will suggest are: 

  • Foundation Repair with Pier Installation  

Foundation piers are one of the most reliable structural repair tools. By transferring weight from unstable or unreliable soil onto competent, load-bearing strata far below the frost line they stabilize and can lift even the most damaged of foundations. There are different kinds of foundation piers that may be utilized. The first kind, push piers, relies on the weight of your property to push them firmly into the soil and set them in place. Another type, helical piers, are effectively screwed into the soil and distribute the weight of a structure more widely. A third kind, slab piers, are used specifically for homes with slab foundations. All these solutions are meant for foundation repair and may or may not be appropriate for your concrete issues. Be sure to consult with a foundation and concrete repair expert for a free inspection and recommendations for solutions that will meet your home’s specific repair needs.  

  • Polyurethane Foam Injection 

Generally speaking, polyurethane foam injection is the successor to mudjacking. Both use the principle of creating pressure below a sunken or uneven surface to lift and stabilize it, but whereas mudjacking uses a heavy cement slurry, polyurethane foam is lightweight. Polyurethane foam is a wonderfully powerful, versatile, and stable substance which can lift even very heavy surfaces into place with relative ease. It is preferable to foundation pier installation in many cases because the installation process for polyurethane foam is much less disruptive and requires no serious excavation or drilling. PolyRenewal™ is without a doubt one of the most popular polyurethane foam injection systems on the market today!   

How We Fix Uneven Flooring with PolyRenewal™

Here at Innovative Basement Authority, we favor the PolyRenewal™ system for raising sunken concrete slabs and floors. Pier installation has its place and could very well be a viable solution for you. But other areas may benefit from PolyRenewal™ foam injections that can address the cause of sinking as well as the symptoms. This dense, expanding polyurethane foam has an incredible load-bearing capacity and is minimally invasive. The installation process goes like this:   

  • Excavation  

If the concrete slabs are covered by tiles, carpets, or any other kind of flooring, small sections will be lifted to allow access to the affected slabs. Our team will ensure that as little of your flooring is disturbed as possible.  

  • Drilling  

We will drill small holes, no bigger than a penny, into the affected slabs. This is a quick and minimally invasive procedure. Our team will do their best to make as little noise as possible while undertaking this step.  

  • Injection  

After injection ports are placed in the drilled holes, specially tailored polyurethane foam is then injected underneath the concrete slab. This foam will expand once injected, lifting sunken slabs as it does so. Once the concrete floor is appropriately lifted, we will stop injecting and the material to cure. PolyRenewal™’s quick cure time of 15 minutes means you can use your concrete slab floor the same day this solution is installed.  

  • Restoration  

Once we have finished lifting your concrete slabs, we will cover the drill sites and restore your flooring to its former state. This means that you can go about your day without worrying about tidying up after our team.  

As you can see, this is a relatively simple and quick process that does not involve large amounts of excavation. It is our goal that you should be able to go about your day both during the process and directly after our team leaves your home with minimal disruption and noise.  

What Sets PolyRenewal™ Apart?  

You have many options when it comes to fixing your concrete slabs and flooring, but we believe that PolyRenewal™ is the best choice for those with uneven or depressed interior slabs. It is our preferred solution in most concrete lifting scenarios.


This is because PolyRenewal™ is: 

  • Incredibly Strong  

Pound for pound, PolyRenewal™ has more lifting power and carries more weight than generic polyurethane foams. It has more lifting power than mudjacking. This means that you can be certain that your flooring will stay lifted and stabilized.  

  • Lightweight  

While some of the heaviest filler materials can weigh 120lbs per cubic foot, PolyRenewal™ foam weighs only 4lbs per cubic foot. This makes it perfect for use on weaker soils. 

  • Waterproof  

PolyRenewal™ foam is suitable for water displacement and will not wash away, no matter how much water it comes into contact with. This also means that it will not allow water into your home, of course, which is a huge benefit.  

  • Inert and Stable  

PolyRenewal™ will not react with moisture or soil and will not impart harmful chemicals or toxins into it.  

  • Easy to Install  

Compared to other solutions, the installation process is quick, quiet, and very cost-effective. PolyRenewal™ can be installed by our expert teams in a few hours, and you can use your lifted and repaired concrete within the same day.  

  • Durable  

Once cured, PolyRenewal™ is very durable. It will not crack, crumble, or wash away. This means that you get a truly long-term solution.  

Our team recommends PolyRenewal™ because we are well-versed in all the solutions that we offer and have determined that this is the best option for a property which has issues with interior slabs. We recommend this as an alternative to older methods like mudjacking because it is more efficient, effective, and versatile.   

What Can Cause Uneven Flooring in a Property?   

Concrete slab floors are durable but notoriously prone to sinking and the formation of irregular depressions. Two main factors contribute to this. First, there is the porous nature of poured concrete. Secondly, concrete floors or foundations are often poured over unsuitable soil. 

Because poured concrete is porous, it absorbs water from the soil underneath it. If the soil under your home has stable moisture levels, this should not be a huge problem. If, however, your soil is prone to fluctuations in its moisture levels, you could quickly see cracks forming in concrete floors. 

When the soil under your home is saturated, the excess hydrostatic pressure will push against your foundation and flooring and the rate of water absorption will increase. This will undermine the stability of the affected concrete, making it softer, and can cause subsidence in your home as a whole. When this occurs, uneven pressure will be put on certain parts of your flooring; cracks and uneven floors are sure to follow. 

If the soil under your home becomes excessively dehydrated, however, or begins to erode, you are far more likely to see localized sinking. This is called settlement and occurs when large cracks open up in the soil as it shrinks; with no support, sections of a foundation can sink into these cracks and cause unevenness and depressions in the flooring above. 

Problems Associated with Uneven or Cracked Flooring  

Of course, the tripping hazard uneven flooring represents is a huge issue, but there are other, more insidious problems that can arise as a result of this kind of damage. The most common is dampness, which occurs when water seeps up through the cracks in your property’s foundation and flooring. 

You will be able to see this through water pooling in your basement, cracks which seem to be darker than the floor around them or which have a darker outline, and through sudden rises in humidity in your home. You may also notice mold and mildew formation and a musty odor, concentrated in rooms that are affected by uneven and cracked flooring. Over time these issues can also lead to other, more pressing problems like widespread structural instability and serious pest infestations. 

So, it’s better to deal with cracks and sunken sections of concrete flooring before the situation begins to escalate.  

Interior Slab Lifting


There are several potential reasons as to why your property’s concrete floors could be uneven. Identifying the contributing factors can be fairly complicated, but there are some simple signs that you can look for to help you get an idea of what’s going on. First, consider whether the floor is tilted consistently from one side of the room to the next, or whether it has inconsistent dips and depressions. If the tilt is even, it is most likely being caused by subsidence; if there are inconsistent dips, you may be dealing with settlement or sunken concrete slabs.  

  • Subsidence  

If you have an even tilt across the whole of your flooring, you are most likely looking at a problem such as subsidence. Caused by oversaturation in the soil, subsidence is the sinking of your property foundation (usually in an uneven manner). This can lead to many issues from uneven floors to cracks, and even more serious problems like bowed walls.  

If a professional determines that subsidence is the main cause of your uneven flooring, you will most likely be looking at pier installation to rectify the issue. However, you may also have inconsistently depressed sections of flooring. This can be caused by cracking and damage to your foundation as a result of increased pressure on certain points as your property sinks. In these cases, more than one repair method may be suggested.  

  • Settlement  

Settlement is most commonly caused by excessive soil dehydration. Certain kinds of soil can shrink dramatically when they become dehydrated. When this happens, large chasms can open up in the soil, leaving sections of your foundation unsupported. One of the main results of this is the ‘settling’ of some parts of your foundation and flooring into the space left behind.  

This has many implications for your property as a whole, but one of the most consistent and insidious co-occurring issues that comes with settlement is dampness. Once cracks open in your flooring, dampness will inevitably seep up into your home. This can lead to mold and mildew formation and increased humidity in your home, and cause musty odors to take root.  

The presence of sunken concrete slabs in a home is always a bad sign, of course, but the reasons to worry about it can be split into personal and structural issues.  

Sunken Concrete Slabs are a Personal Hazard 

One of the biggest reasons to be concerned about the presence of uneven or sunken concrete slabs inside your home is the fact that they can present a tripping hazard. Any kind of unevenness or even an obstruction on the floor can cause a tripping hazard, but sunken or uneven concrete slabs are one of the most serious potential tripping hazards which can exist in a home.  

Anyone can be at risk of tripping, but those who are already vulnerable are by far the most at risk. This means that anyone in your home or family who has mobility issues, who is elderly, or who is very young (for example toddlers) will be at heightened risk of accidental falls and injury when there are sunken slabs in your home. What’s more these people are also more likely to face severe injury if they fall on concrete flooring. This means that slab levelling and repair should be a priority.  

Sunken Concrete Slabs Can Hide Larger Issues 

Sunken, uneven, or damaged concrete slabs inside a home can be the tip of a proverbial iceberg. The underlying issues which this kind of damage can be an indicator for ranges from localized issues like burst pipes and flawed slabs to wider structural issues like foundation damage and structural movement. There is also a high chance that these underlying causes can lead to secondary issues, too.  

The most common co-occurring and underlying issues which may be present in homes which have damaged or sunken interior slabs are foundation settlement, foundation subsidence, bowing walls, and dampness and humidity. Dampness and humidity are likely to be present in any home with structural issues, and will lead to tertiary issues like mold formation and wood rot. 

The precise measuring required to ensure that PolyRenewal™ polyurethane foam expands to the proper degree, and with the proper force, is just one of the reasons that DIY installation can be risky.  

  • Incorrect Formulation Could Cause Issues 

One of the main risks of over or under measuring one of the two parts of PolyRenewal™, is the over or under expansion of the mixture. This is not only inconvenient, but it could present some risks for your home and wellbeing. While PolyRenewal™ will not leak chemicals into the soil, it definitely shouldn’t be coming into contact with your skin.  

Furthermore, if the foam over expands it could cause a bulge or hump in your flooring and cause more damage. Rectifying this issue is likely to require the removal and replacement of that concrete slab. If the foam under expands, by contrast, you could get away with hiring a professional to provide a tailored solution, but the worst-case scenario could also see serious excavation in your home.


  • This May Not Always Be the Best Solution 

While the PolyRenewal™ system is phenomenal, it’s not suited to every single situation. This is why it is important to consult an expert who will be able to tell you if this is the best solution for your home.   There are a number of factors which a professional must consider when it comes to deciding the best response to sunken or unlevel interior slabs.  

There are other benefits to professional services. As well as making sure that you get the best solution for your home, professionals can also guarantee a certain standard of work. Furthermore, professional products and services come with guarantees and warranties. So, whether PolyRenewal™ is the best solution or not, having a professional on board is definitely the best choice because of the benefits attached to it. 

Innovative Basement Authority is Here to Help You 

If you notice your interior slabs are cracking and uneven, don’t delay in fixing them, as they could result in bigger and more expensive problems down the road. For assistance from trusted experts, contact the professional team at Innovative Basement Authority today for a free inspection and repair quote. After completing a thorough evaluation of your home, we’ll provide you with a free services quote with recommended repair solutions to permanently stabilize and help lift the problematic concrete in your home. 

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We service Minnesota, North Dakota, South Dakota and Eastern Montana for basement waterproofing and crawl space repair.

Fargo, ND

1330 41st St. N
Fargo, ND 58102

Minneapolis, MN

6265 Carmen Ave.
Inver Grove Heights, MN 55076

Rush City, MN

1325 S Frandsen Ave
Rush City, MN 55069

Sioux Falls, SD

101 S. Reid Street, Suite 307
Sioux Falls, SD 57103