Most people are familiar with the concept of concrete leveling once they actually encounter an issue with uneven or unsettled concrete surfaces on their property. If you are in that situation, don’t worry; we can help you understand and address it. Let’s dive into the fundamentals of leveling the concrete so you can grasp how it works and recognize when the repair method is necessary.
What is Concrete Leveling?
Concrete leveling is a repair process that addresses sunken or uneven concrete surfaces. Over time, the soil underneath concrete slabs can shift or erode, creating voids that cause the concrete to settle unevenly. Concrete finishing restores this issue by drilling holes into the settled slab and pumping a grout-like material beneath it. This material fills the empty spaces, providing a stable base that raises the concrete to its original position. It’s a cost-effective solution for fixing trip hazards and restoring the appearance of concrete surfaces like driveways, patios, sidewalks, and pool decks.
How Does Concrete Leveling Work?
The process of repairing the concrete follows a few key steps. First, we strategically drill holes around the perimeter of the sunken area. The hole size varies based on the leveling material used. Next, the leveling compound, such as polyurethane foam, grout, or compacted stone, is pumped through the holes, filling the voids underneath the slab. The concrete slab is gradually lifted back into position as the void spaces fill. Finally, we seal the holes to complete the repair once the desired level is achieved. This process is done without requiring jackhammers or heavy equipment, making it a minimally invasive solution.
4 Most Common Methods to Level Concrete
Concrete repair is often necessary to level sunken or uneven slabs, but not all methods are equally effective or long-lasting. Concrete lifting experts recommend these four most common leveling techniques explained below:
1. Polyurethane Foam Injection
This modern method involves drilling small holes into the sunken concrete slab and injecting expanding polyurethane foam underneath the concrete. As the foam expands, it fills any voids in the soil, compacts the ground, and exerts upward pressure to lift and re-level the concrete. The cured polyurethane foam also binds to the concrete, adding structural strength. Polyurethane injection cures rapidly in just 30 minutes and provides a long-term, waterproof solution with minimal disruption.
2. Mudjacking
One of the oldest leveling techniques, mudjacking, uses a liquid slurry from cement, soil, sand, and water. This grout is pumped under pressure through holes drilled in the sunken slab to fill voids and float the concrete upwards. While effective initially, mud jacking can erode over time from moisture exposure, causing the slab to resettle. It also requires precise slurry consistency and skilled installation to prevent future issues.
3. Cement or Stone Slurry Grouting
An alternative to traditional mudjacking, this method combines aspects of polyurethane injection by using a limestone-based grout mixture pumped through larger drilled holes. The thick slurry effectivity fills voids while adding significant weight to compress and stabilize the soil underneath. It is more environmentally friendly than polyurethane but also more costly.
4. Self-Leveling Concrete
Rather than lifting the existing slab, self-leveling toppings made from polymer-fortified cement are poured over the top to create a new smooth surface for interior floors. This method is best suited for small patching jobs rather than major structural lifting projects. It is an affordable DIY option if installed correctly, but there is a risk of failure, leading to more expensive repairs later.
Benefits and Drawbacks of Concrete Leveling
While concrete leveling can be an attractive option for balancing concrete surfaces, it’s still important to understand its advantages and disadvantages before making the decision.
Key Benefits:
- Cost-Efficiency: The most significant benefit of leveling is the substantial cost savings versus complete concrete replacement. By lifting and stabilizing the existing slab, leveling typically costs 30-70% less than demolishing and repouring new concrete.
- Rapid Process: Leveling crews can usually complete an entire job in less than a day. This eliminates the extended downtimes of total replacements waiting for new concrete to cure properly, allowing rapid return to service.
- Minimal Disruption: Leveling avoids the need to demolish and remove existing concrete, creating far less mess, noise, and disruption to the property during the repair process.
- Seamless Appearance: By utilizing the original slab, leveling maintains a seamless, integrated look with adjoining concrete areas that are extremely difficult to achieve with new pours attempting to blend in.
Potential Drawbacks:
- Existing Cracks Remain: While leveling corrects elevation issues, it does not repair any pre-existing cracks in the slab. These will still be visible after leveling, though they can be filled and sealed.
- Variability in Outcomes: Subsurface conditions like soil compaction can impact leveling results in ways that may only become evident once work begins. Experienced contractors can adapt, but they can’t guarantee perfect outcomes.
- Ground Dependence: Similar to total replacement, the long-term stability of leveled concrete relies on the integrity of the underlying base material or soil. Subpar ground conditions could lead to renewed settling over time.
When to Level Your Concrete?
Adjusting your concrete can be an appropriate solution when dealing with issues like:
- Slabs that have become uneven, creating tripping risks
- Indoor floors that have sunken or sloped
- Areas where soil erosion has left voids under slabs
- Outdoor steps that are no longer of appropriate level
- Improper water drainage around foundations caused by shifted concrete
When Not to Level Your Concrete?
However, concrete adjustment may not be the best solution if:
- The concrete itself is severely damaged or falling apart
- You wish to modify the appearance or texture of the surface
- Tree roots have lifted sections of concrete excessively high
- You need to change the fundamental design or intended use of the concrete
What Causes Concrete to Sink?
The main causes of concrete sinking are poor soil conditions underneath, such as inadequately compacted or low load-bearing soil. Other factors include soil erosion, expansive soils, excessive moisture, improper reinforcement, and insufficient curing during installation.
What Is the Cost of Concrete Leveling?
The cost of lifting a sunken concrete slab depends on the extent of damage, size of the area, repair method used, amount of material required, labor costs, and any permit fees. The best way to get an accurate price is to have a professional contractor inspect the site and provide a quote.
Conclusion
Concrete leveling is an effective and cost-efficient solution for repairing sunken or uneven concrete surfaces, offering minimal disruption and a seamless appearance. By understanding the various methods, benefits, and limitations, homeowners can make an informed decision when addressing concrete settlement issues on their properties. With proper assessment and execution by professionals, concrete lifting can extend the lifespan of existing concrete while avoiding the higher costs of complete replacement.
