1. Introduction

Concrete lifting, also known as slab jacking or mudjacking, is a process used to raise and level sunken or uneven concrete surfaces. Over time, concrete can sink due to soil erosion, poor compaction, or water damage. Instead of replacing the entire slab, concrete lifting offers a more cost-effective and quicker solution to restore the surface.

2. The Process of Concrete Lifting

Step 1: Assessment

A professional assesses the damaged concrete to determine the cause of the sinking and whether concrete lifting is a viable solution.

Step 2: Drilling Holes

Small holes (usually around 1 to 2 inches in diameter) are drilled into the sunken concrete slab.

Step 3: Pumping the Material

A specialized mixture, such as a slurry (for mudjacking) or polyurethane foam (for polyjacking), is pumped through the holes to fill the voids beneath the slab. This mixture expands and lifts the concrete back to its original position.

Step 4: Sealing the Holes

Once the slab is leveled, the holes are patched with cement or another material to blend with the rest of the surface.

Step 5: Curing

The area is allowed to cure, ensuring the lifted slab is stable and usable. Depending on the material used, curing times may vary (polyurethane foam sets faster than a traditional slurry).

3. Cost of Concrete Lifting

The cost of concrete lifting depends on various factors, including:

• Size of the area: Larger areas will require more material and labor.
• Type of lifting material: Polyurethane foam tends to be more expensive than a traditional slurry mix.
• Severity of the damage: More complex issues (like extensive voids or deeply sunken slabs) may increase the cost.

Average Cost:

• Mudjacking: $3 to $6 per square foot
• Polyjacking (polyurethane lifting): $5 to $25 per square foot

On average, homeowners can expect to spend between $500 to $1,500 for typical concrete lifting jobs.

4. Types of Concrete Lifting

1. Mudjacking (Slab Jacking)

• Process: A slurry mixture (typically made of cement, sand, and water) is pumped under the slab to lift it.
• Pros: Cost-effective, reliable for larger areas.
• Cons: Slower curing time and heavier material that may cause future settling.

2. Polyurethane Foam Injection (Polyjacking)

• Process: Lightweight polyurethane foam is injected beneath the slab, expanding and lifting the concrete.
• Pros: Faster curing time, long-lasting, and lightweight material that reduces the risk of future settling.
• Cons: More expensive than mudjacking.

3. Sand or Grout Pumping

• Process: Similar to mudjacking, but instead of a slurry, a sand or grout mixture is used.
• Pros: Effective for certain large projects.
• Cons: Less common and may not be ideal for smaller jobs.

5. Frequently Asked Questions (FAQ)

Q1: How long does concrete lifting last?

Concrete lifting, especially with polyurethane foam, can last for decades. The durability depends on the quality of the material and the soil conditions underneath.

Q2: How long before I can use the area after lifting?

With polyurethane foam, the area can typically be used within 15 minutes to a few hours. Mudjacking, however, may require up to 24 hours to fully cure.

Q3: Is concrete lifting better than replacement?

In most cases, concrete lifting is a more cost-effective and less disruptive solution than replacement. It’s ideal for fixing uneven surfaces and sunken slabs without the need for demolition.

Q4: Can all concrete surfaces be lifted?

Most concrete slabs, including sidewalks, driveways, patios, and pool decks, can be lifted. However, severely damaged or cracked slabs may need replacement instead of lifting.

Q5: What causes concrete to sink?

Common causes include soil erosion, water damage, poor soil compaction, or settling of the ground beneath the slab.

Conclusion

Concrete lifting is an effective solution for repairing sunken or uneven concrete slabs without the need for full replacement. With different methods like mudjacking and polyjacking, homeowners can choose the most suitable option based on their needs and budget.