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PolyRenewal injection for concrete repair

Interior Slab Leveling

PolyRenewal™ can restore your unlevel interior slabs to their original condition

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Sinking concrete slab floor
Sinking concrete slab floor

Do you have uneen or unlevel floors in your home? Have you noticed cracks or separations in doorways? If so, you may need interior slab leveling to restore your floors. Concrete slabs sink and settle over time, and allowing them to go unrepaired can cause serious damage to your home.

At Complete Basement Systems, we provide quality interior slab leveling with PolyRenewal™. PolyRenewal™ is a non-invasive technique that can raise your floor back to its original position and provide a long lasting solution. Click below to learn more! We offer free estimates on all our work in Denver, Colorado Springs, Cheyenne, Aurora and throughout the nearby areas.

What causes uneven floors in a home?

Concrete slabs are often poured on wet, weak, or poorly compacted soil. Over time, this will lead to settlement of the slab, causing uneven floors or cracking. Inside your home, your floor will pull away from walls and doorways, creating gaps at the seams.

This not only creates an uncomfortable home with tripping hazards, it also significantly impacts property value. When prospective buyers have to deal with foundation issues, it can make selling a home very challenging.

How we repair sunken interior slabs with PolyRenewal™

There are several traditional methods of raising concrete slabs, including spreading self-leveling compounds, mudjacking, and pier installation. However, these methods can be very invasive and often don’t fix the source of the problem.

Interior Slab Leveling


Before you even figure out how to fix uneven floors in a home, you’ll first want to learn what causes them. Several reasons might cause a home to develop uneven concrete floors. 

  • Weak Soil and Heavy Weight 

If the soil underneath the concrete slab was already weak, the chances of having uneven concrete slabs go up substantially. That’s because weak soil often reacts easily to pressure and weight, both things that a concrete slab often has in ample measure. Typically, this occurs if the initial construction crew didn’t prepare the soil properly. 

If you’ve placed too much weight on a concrete slab, you may also have uneven slab problems that have nothing to do with an inherent issue of the concrete. This doesn’t happen frequently, but it is possible for there to be serious movement problems if you add something heavy, like marble countertops, on top of a concrete slab. 

  • Erosion Under the Slab 

Erosion underneath your home’s concrete slab is a possible concern, especially if you suddenly experience a lot of rain or floodwater in an area and your home doesn’t have a basement or crawl space. Erosion underneath the concrete slab typically causes all sorts of movement problems and it can devolve into issues with sinking. 

Soil erosion is a surprisingly common concern. It can be much worse in areas that have especially expansive soils, as it can sometimes move away with water more easily. You might want to talk to an expert if you have a lot of water around your home to make sure you’re avoiding erosion as much as possible.

How can you notice that your concrete slabs are sinking? Although it can become more obvious when the problem becomes serious, the warning signs of sunken concrete slabs can also be less obvious, which is why you need to understand them more effectively. 

  • Uneven Floors 

Probably the most obvious sign of sunken concrete slabs is uneven floors. If your floor seems uneven, especially if it’s tilting down dramatically at one end, it’s almost certainly going to be because the concrete is itself sinking and that’s usually because you’re experiencing issues with the soil underneath the concrete. 

Another area where it’s common to see issues with sinking concrete slabs is the center of the floor. If you’re noticing that all the edges of the floor seem to be normal, but the center seems to be sinking slightly, chances are you’re experiencing soil erosion only under the middle of the concrete. This is common with freezing and thawing concerns as well as expansive soils

  • Cracks Between Floors and Walls 

It’s also possible to screen for sunken concrete slabs by looking at the area between the floors and the walls. If you notice that there are cracks between the floors and the walls, especially if those cracks seem like they’re widening, you’re probably going to see issues with your concrete slab. 

Your floors should always be flush with your walls. If there’s an opening between your floor and wall, you are looking at a problem regardless of whether or not sunken concrete slabs are causing it. Make sure you’re keeping an eye out for cracks that have opened between the floors and walls so you can take steps to fix this problem early on.

PolyRenewal™ is a form of polyurethane foam injection that can be extremely beneficial for leveling interior concrete slabs. Here are just a few of the reasons that polyurethane foam injections can be so great for your leveling needs. 

  • Fast-Acting and Effective 

PolyRenewal™ is extremely fast-acting. Especially when compared to slab leveling options like slabjacking or mudjacking, PolyRenewal™ works extremely quickly. PolyRenewal™ can reach 90% rigidity within only 30 minutes, which makes it perfect for locations that sustain a lot of foot traffic. If you’re looking for a way to use your slab as soon as possible after it’s fixed, PolyRenewal™ is a good option. 

One of the reasons that homeowners opt for concrete filling is because they feel like it’s the most effective option. However, that’s not true. Even the United States Department of Transportation has used polyurethane foam injections for concrete lifting because they’re extremely useful. They can even be more effective than concrete filling because they expand to fill the entirety of an erosion area. 

  • Less Intrusive 

Above all, PolyRenewal™ is substantially less intrusive than other methods of interior slab leveling. When you use concrete filling methods of slab leveling, you’ll need to stay away from the area for typically around two weeks, and the holes in your concrete will typically need to be about the size of a soda can. This is monumentally intrusive. 

In contrast, PolyRenewal™ only requires holes about the size of a penny, and you can start using the area within about 30 minutes. Not only is it less intrusive when it comes to your concrete slab, but it’s also much less intrusive in your life as a whole. This makes it much better for busy families that may need to use the slab quickly.

It’s important to prioritize interior slab leveling if at all possible. When you have interior slab issues, you need to make sure you’re addressing them appropriately. Otherwise, you could end up dealing with a variety of interior slab problems. 

  • Annoying Floors 

The first problem is generally a cosmetic problem rather than a serious problem, but it’s still something you should think about. When you don’t fix your interior slab problems, you’re always going to have to deal with those annoying floor problems, including issues with the floors slanting. 

Even though this annoyance isn’t the main reason you should try to fix your uneven slabs, it’s a powerful force of change. Many homeowners finally fix their uneven slabs because they’re frustrated that they always have sticking doors and windows or similar problems. It can be an extra reason to take care of your home. 

  •   Foundation Problems 

The much more serious problem that you could run into if you avoid handling your interior slabs is that you could develop foundation problems from the concrete issues. Concrete repair is always important to prioritize because it’s such a crucial element of structural stability. It’s common for foundation problems to come around because of certain concerns like uneven floors and erosion underneath the home. This is the real reason you need to fix your uneven slabs. Sure, annoyance can push you toward the final goal, but knowledge of foundation problems will be much more likely to drive change. Schedule a free inspection with Complete Basement Systems to start your journey toward a healthier basement, starting with interior slab leveling.

PolyRenewal™ is the solution to these problems. This is how the PolyRenewal™ system works to raise your sunken slab:

  • Very small sections of existing finished flooring are removed to access slab
  • Penny sized holes are bored into the slab in each affected room
  • Polyurethane foam is injected through holes, where it expands and raises the slab
  • Foam is injected until the floor is level, reaching 90% rigidity within 30 minutes
  • Finished flooring is restored over injection holes

With our system, you get the best solution for sunken concrete available without creating significant upheaval in your home.

Call us for a free estimate on slab repair in Greater Denver

If you have issues with an unlevel floor or sunken interior concrete slab in your home, call the experts at Complete Basement Systems today for a quality solution. We can provide a non-invasive, fast, and effective repair with PolyRenewal™.

Contact us online to learn more about how PolyRenewal™ can make the difference for your home. We offer free estimates on all our concrete lifting services in Denver, Colorado Springs, Aurora, Littleton, Cheyenne, Fort Collins, Thornton, Arvada, Westminster, Boulder and throughout the surrounding areas.

Serving Greater Denver area, Colorado Springs, Eastern Colorado, and parts of Nebraska and Wyoming

Colorado Springs, CO

707 County Line Rd.
Palmer Lake, CO 80133

Denver, CO

4686 Ivy St
Denver, CO 80216