Concrete leveling, often referred to as slabjacking or polyjacking, is primarily accomplished through a modern and efficient technique known as polyurethane foam injection. This method effectively lifts and levels sunken concrete slabs by filling voids beneath them.
The Polyurethane Foam Injection Process
The polyurethane foam injection method is a precise and minimally invasive way to address uneven concrete. It involves a series of carefully executed steps to ensure the slab is lifted to its correct position.
Step-by-Step Foam Injection
- Preparation & Drilling Small Holes: To begin, small dime-sized holes are drilled into the sunken sections of your concrete slab. These strategically placed holes are typically just 5/8-inch in diameter, making them almost unnoticeable once the process is complete.
- Polyurethane Foam Injection: Once the holes are drilled, a specialized port is inserted, and expanding polyurethane foam is injected into the holes. This high-density foam starts as a liquid but rapidly expands, flowing into and filling any voids beneath the concrete slab.
- Lifting & Leveling: As the foam fills the space below, it creates upward pressure, gently lifting your slab until the uneven section is leveled with the rest of the concrete. The injection process is carefully monitored by technicians to ensure precise lifting and to prevent over-lifting.
- Finishing Touches: After the concrete is leveled, the injection ports are removed, and the small holes are patched with a non-shrink grout or a concrete repair compound, leaving a smooth, clean finish.
Why Concrete Sinks
Concrete slabs often sink due to issues with the soil beneath them. Common causes include:
- Soil Erosion: Water runoff, leaky pipes, or poor drainage can wash away soil particles, creating voids.
- Poor Compaction: Soil that was not properly compacted during initial construction can settle over time.
- Shrinking Soils: Some soil types, particularly expansive clays, can shrink significantly during dry periods, leading to voids.
- Heavy Loads: Over time, heavy loads on the concrete can cause the underlying soil to compact and settle.
Benefits of Polyurethane Foam Leveling
This modern concrete leveling technique offers numerous advantages over traditional methods like mudjacking:
- Minimal Disruption: The small holes required are less invasive than larger holes needed for other methods, preserving the aesthetic of your concrete.
- Fast Curing & Use: The injected foam cures rapidly, often allowing the concrete to be used within minutes to an hour of the repair.
- Lightweight Material: Polyurethane foam is significantly lighter than traditional concrete slurry, adding minimal weight to the soil beneath and reducing the risk of future settlement.
- Durable & Long-lasting: The foam is resistant to moisture and erosion, providing a stable and durable solution that addresses the root cause of sinking.
- Environmentally Friendly: Many polyurethane foams used in leveling are inert and non-toxic once cured, posing no threat to the environment.
Common Applications
Polyurethane foam leveling is suitable for a wide range of residential and commercial concrete surfaces, including:
- Driveways
- Patios and Pool Decks
- Sidewalks and Walkways
- Garage Floors
- Basement Floors
- Commercial Slabs and Warehouse Floors
Key Features of Polyurethane Foam Leveling
| Feature | Description |
|---|---|
| Hole Size | Small, dime-sized (approx. 5/8 inch) |
| Material | Expanding polyurethane foam (high-density, lightweight) |
| Lifting Mechanism | Foam expands to fill voids and lift slab |
| Curing Time | Rapid (minutes to an hour for use) |
| Durability | Water-resistant, long-lasting, prevents future settlement |
When to Consider Professional Leveling
While the concept is straightforward, concrete leveling with polyurethane foam requires specialized equipment and expertise. It's recommended to consult with experienced professionals who can accurately assess the cause of the sunken concrete and determine the precise amount and placement of the foam needed for effective leveling. You can find local specialists by searching for terms like "concrete leveling services near me" or "polyjacking companies."
Frequently Asked Questions
How long does the concrete leveling process take?
Most residential concrete leveling projects can be completed in just a few hours, depending on the size and complexity of the area. The fast curing time of the foam allows for immediate or near-immediate use of the surface.
Is polyurethane foam leveling durable?
Yes, the high-density polyurethane foam used in concrete leveling is designed to be highly durable and resistant to moisture and erosion, providing a long-lasting solution to prevent future sinking.
What about the cost of concrete leveling?
The cost of concrete leveling varies based on factors such as the size of the area, the amount of material needed, the severity of the sinking, and your geographical location. Obtaining multiple quotes from reputable contractors is always a good idea.
By utilizing expanding polyurethane foam injected through small, dime-sized holes, concrete leveling effectively restores the stability and appearance of sunken slabs with minimal disruption.
