Over time, concrete surfaces such as driveways, sidewalks, garage floors, and even foundations can settle and become uneven. This is not only a cosmetic issue but can also be a safety hazard and a sign of underlying structural problems. Traditionally, the solution involved removing and replacing the sunken concrete, which is both costly and time-consuming. Fortunately, a more efficient and cost-effective method has emerged: polyurethane concrete raising. Also known as polyurethane foam jacking or polyjacking, this technique has revolutionized how homeowners and contractors deal with sunken concrete.
What Is Polyurethane Concrete Raising?
Polyurethane concrete raising involves injecting high-density polyurethane foam beneath the surface of a concrete slab. The foam expands, filling voids and lifting the slab back to its original position. This technique is a modern alternative to traditional methods like mudjacking and concrete replacement.
The process is simple yet effective:
- Small holes (about 5/8 inch) are drilled into the concrete slab.
- Polyurethane foam is injected into the holes.
- The foam expands rapidly, lifting the concrete.
- Once the slab is level, the holes are patched.
The entire procedure is usually completed within a few hours and the surface is ready for use the same day.
Benefits of Polyurethane Concrete Raising
1. Cost-Effective
Compared to full concrete replacement, polyurethane concrete raising can cost 50–75% less. Because the process requires fewer materials, less labor, and minimal equipment, it’s a budget-friendly solution for homeowners and property managers.
2. Quick Installation and Cure Time
One of the major advantages of polyurethane foam over other lifting methods is its quick curing time. Most surfaces can be walked on or driven over within 15–30 minutes after the injection process.
3. Minimally Invasive
The equipment used for polyjacking is compact, and the holes drilled are significantly smaller than those used in traditional mudjacking (5/8 inch vs. 1.5–2 inches). This results in less visible patchwork and a cleaner finish.
4. Lightweight Material
Polyurethane foam is much lighter than the cement slurry used in mudjacking. This means it is less likely to cause further soil compression and resettling over time.
5. Water-Resistant
Polyurethane foam is closed-cell, meaning it does not absorb water. This is important because it prevents the injected material from contributing to erosion or water damage beneath the slab.
6. Environmentally Friendly
Some types of polyurethane foam are made with recycled materials, making them a more sustainable choice. Additionally, by restoring rather than replacing existing concrete, you reduce waste and minimize the carbon footprint associated with demolition and new concrete production.
Common Applications
Polyurethane concrete raising can be used in a wide variety of settings, including:
- Driveways and Sidewalks: Correct trip hazards caused by uneven surfaces.
- Garage Floors: Restore level surfaces for vehicles and storage.
- Patios and Pool Decks: Maintain aesthetics and safety.
- Basement Floors: Address settling and foundation issues.
- Warehouse and Industrial Floors: Ensure even surfaces for heavy machinery and improve safety.
- Highways and Roadways: Restore level driving surfaces with minimal disruption to traffic.
How It Compares to Mudjacking
Mudjacking is another popular method for lifting sunken concrete. It involves pumping a mixture of water, soil, sand, and cement (known as “slurry”) beneath the concrete slab.
Here’s how polyurethane concrete raising compares:
| Feature | Polyurethane Foam | Mudjacking |
|---|---|---|
| Hole Size | Small (5/8 inch) | Large (1.5–2 inch) |
| Cure Time | 15–30 minutes | 24–48 hours |
| Weight | Lightweight | Heavy |
| Longevity | Long-lasting | Can settle again |
| Material | Waterproof foam | Cement-based slurry |
| Environmental Impact | Lower | Higher due to materials and waste |
In most residential applications, polyurethane is the preferred method because of its speed, cleanliness, and long-term performance.
Is It a DIY Project?
While there are polyurethane foam kits available for small repairs, concrete raising is typically not recommended as a DIY project. The process requires specialized equipment and expertise to ensure even lifting and to avoid damaging the slab. Improper application can result in cracks, over-lifting, or even worse settling later on.
Hiring a professional ensures:
- Accurate slab leveling
- Proper injection technique
- Minimal damage to surrounding areas
- Long-term performance and warranty
What Causes Concrete to Settle?
Understanding why concrete settles in the first place can help in preventing future issues. Common causes include:
- Soil Erosion: Water runoff can wash away soil beneath slabs.
- Poor Compaction: If the soil wasn’t properly compacted before pouring concrete, it may compress under the weight.
- Freeze-Thaw Cycles: In colder climates, expanding and contracting soil can shift slabs.
- Tree Roots: Growing roots can push up or displace concrete slabs.
- Heavy Loads: Vehicles or heavy equipment can cause concrete to sink if the subgrade is weak.
Preventive measures like proper drainage, sealing cracks, and strategic landscaping can help reduce the risk of settlement.
Cost of Polyurethane Concrete Raising
The cost varies based on location, the extent of the damage, and the size of the area needing repair. On average:
- Small repairs (single sidewalk panel): $250–$500
- Driveways and patios: $500–$2,500
- Larger projects: $3,000 and above
Although this is more expensive than mudjacking in some cases, the superior results often make it worth the investment.
Choosing the Right Contractor
When hiring a contractor for polyurethane concrete raising, consider the following:
- Experience: Look for companies that specialize in foam jacking.
- Reviews: Check online reviews and ask for references.
- Warranty: A good contractor will stand behind their work.
- Licensed and Insured: Always confirm the company is properly certified.
- Detailed Estimate: Get a written estimate outlining the scope, cost, and timeline.
Conclusion
Polyurethane concrete raising is a modern, efficient, and long-lasting solution to uneven concrete problems. With benefits like quick installation, minimal disruption, and durability, it’s no surprise that both homeowners and commercial property owners are choosing this method over traditional alternatives. If you’re dealing with sunken concrete, polyurethane foam lifting might be exactly what you need to restore safety and value to your property.
