How Does Concrete Leveling Work? The Step-by-Step Process Explained

You have noticed the trip hazard on your driveway. Or the patio that slopes toward the house instead of away from it.

Someone mentions "concrete leveling" and you wonder: what exactly does that mean? Do they tear out the whole slab?

Not at all. The concrete leveling process is far less invasive, significantly cheaper, and faster than most homeowners expect. Here is how it actually works, step by step.

What Is Concrete Leveling?

Concrete leveling is the process of raising a sunken or uneven concrete slab back to its original position by injecting material underneath it.

The slab itself stays in place. Nothing gets torn out or replaced.

Instead, a specialized material is pumped through small holes drilled in the surface. That material fills the voids beneath the concrete and lifts it back to level.

You may hear this process called different names depending on the method used:

Mudjacking (also called slabjacking or pressure grouting)
Foam jacking (also called poly leveling or polyurethane foam injection)
Limestone slurry leveling (a natural stone-based grout method)

The core concept is identical across all three. The differences lie in the material being injected, the equipment used, and the long-term characteristics of the fill.

To understand why slabs sink in the first place, see our guide on why concrete sinks and settles.

The Concrete Leveling Process: 6 Steps

Whether a crew uses limestone slurry, mud, or polyurethane foam, the workflow follows the same fundamental sequence. Here is what happens from the moment the truck arrives to the moment you can walk on the surface again.

Step 1: Inspection and Assessment

Before any equipment comes off the truck, a technician evaluates the site.

What they are looking for:

The depth and pattern of settling (measured with a level or laser)
The condition of the concrete surface (cracks, spalling, structural integrity)
Potential causes of the settling (drainage issues, soil type, tree roots)
Access to the work area and proximity to structures

This step determines whether leveling is the right solution or if replacement makes more sense.

A general rule: If the concrete is structurally sound (not broken into multiple pieces or crumbling), it is almost always a candidate for leveling.

Step 2: Drilling Access Holes

The technician drills small holes through the concrete slab. These are the injection points where the leveling material will enter.

Key details:

Hole diameter: Typically 5/8 inch for polyurethane foam or 1 to 2 inches for limestone slurry and mudjacking.
Number of holes: Varies by slab size. A typical driveway section might need 4 to 8 holes. A single sidewalk panel may only need 1 or 2.
Placement strategy: Holes are positioned based on where the void is deepest and how the material will flow. The goal is even distribution beneath the entire slab.

The drilling takes only minutes. It creates minimal dust, and the holes are small enough that they are nearly invisible after patching.

Step 3: Injecting the Leveling Material

This is the core of the process. A nozzle or port is inserted into each hole, and the leveling material is pumped beneath the slab under controlled pressure.

What happens underground:

The material flows outward from the injection point, filling voids and cavities in the soil.
As the space fills, hydraulic pressure begins to build beneath the slab.
That pressure pushes the concrete upward, gradually returning it to level.

The technician controls the flow rate and monitors the lift in real time. This is where experience matters most. Too much pressure can over-lift or crack the slab. Too little leaves it short of level.

Step 4: Monitoring and Fine-Tuning the Lift

As material is injected, the crew watches the slab rise. They use a combination of visual reference points, spirit levels, and laser tools to track movement down to fractions of an inch.

The process is iterative:

Inject a measured amount through one hole.
Check the level across the slab.
Move to another hole if a different area needs more lift.
Repeat until the entire surface is even.

For large slabs like garage floors or pool decks, this step may involve cycling between multiple injection points several times.

Step 5: Patching the Holes and Cleanup

Once the slab is level, the injection ports are removed and the holes are filled with a non-shrink cement grout or concrete patch compound.

The patches:

Are flush with the surface
Cure to match the surrounding concrete color over time
Are structurally sound (they won't pop out)

The crew cleans the work area, removes any excess material, and hoses down the surface. Most sites look remarkably clean within minutes of completion.

Step 6: Curing and Return to Use

How quickly you can use the surface depends entirely on the method:

Method	Walk-On Time	Drive-On Time
Polyurethane Foam	15 to 30 minutes	30 to 60 minutes
Limestone Slurry	24 hours	24 to 48 hours
Traditional Mudjacking	24 hours	24 to 48 hours

Foam cures almost immediately because the chemical reaction generates heat and hardens the material within minutes. Slurry and mud-based methods need time for the water content to set and the material to reach full strength.

Leveling Methods: How They Differ

All three methods follow the same six-step process above, but the material injected changes the characteristics of the job significantly.

Limestone Slurry Grout

What it is: A natural blend of crusite limestone, water, and Portland cement.

Best for: Driveways, sidewalks, patios, and areas where long-term weight and stability matter. The material is heavy and dense, which makes it excellent for filling large voids and supporting heavy loads.

Cost range: $3 to $7 per square foot.

Polyurethane Foam

What it is: A two-part chemical compound that expands and hardens after injection.

Best for: Situations where weight is a concern (the foam weighs roughly 2 pounds per cubic foot compared to 100+ pounds for slurry), or where fast return-to-service is critical.

Cost range: $5 to $11 per square foot.

Traditional Mudjacking

What it is: A mixture of water, soil, sand, and cement pumped at high volume.

Best for: Budget-conscious projects where the aesthetic of the drill holes is less important. Mudjacking uses larger holes (1.5 to 2 inches) and is the most affordable option.

Cost range: $3 to $6 per square foot.

For a full comparison of the two most popular methods, see our detailed guide on limestone slurry vs polyurethane foam leveling.

Does Concrete Leveling Actually Work?

This is one of the most common questions we hear, and the honest answer is: yes, but with conditions.

When leveling works exceptionally well:

The concrete is structurally intact (no major fragmentation)
The settling is caused by soil voids, compaction, or erosion
The slab has sunk between half an inch and 4 inches
The underlying cause can be identified and addressed

When leveling is not the right answer:

The concrete is broken into multiple loose pieces
The surface is severely spalled or crumbling
The slab is less than 2 inches thick (common in older pours)
Active tree roots or plumbing leaks are still destabilizing the soil

A reputable contractor will tell you upfront if your situation calls for replacement rather than leveling. If someone says they can level everything regardless of condition, that is a red flag.

How Long Does Concrete Leveling Last?

Longevity depends on two things: the material used and whether the original cause of settling has been corrected.

Factor	Limestone Slurry	Polyurethane Foam
Typical Lifespan	8 to 15+ years	10 to 20+ years
Water Resistance	Moderate (can erode over decades)	High (closed-cell, waterproof)
Soil Compatibility	Excellent (natural mineral)	Good (inert, no soil reaction)
Re-leveling Possible	Yes	Yes, but more difficult

The critical variable: If the gutter is still dumping water next to the driveway, or the grading still slopes toward the foundation, the soil will continue to erode regardless of what material sits beneath the concrete.

This is why we always evaluate drainage and soil conditions before quoting a job. Fixing the symptom without addressing the cause leads to repeat repairs.

For tips on protecting your investment after leveling, see our guide on extending your concrete's lifespan with simple maintenance.

What Makes Colorado Springs Different

The concrete leveling process is the same everywhere, but the conditions in Colorado Springs create unique challenges that affect how the job is planned and executed.

Soil Conditions

The Pikes Peak region sits on a patchwork of soil types. Some neighborhoods are built on stable decomposed granite. Others sit directly on Bentonite clay, which can swell 10% or more when wet and shrink dramatically when dry.

A leveling contractor working in Colorado Springs needs to know which soil type they are dealing with, because it affects material choice, injection volume, and long-term stability.

Freeze-Thaw Cycles

Colorado Springs experiences over 100 freeze-thaw cycles per year. Water enters the soil, freezes, expands by 9%, and then melts, leaving the soil looser than before.

This means leveling work performed in late fall may face immediate stress from winter conditions. Many contractors recommend scheduling leveling in spring or early summer when soil moisture is more predictable and the ground has stabilized after the winter cycle.

Altitude and Temperature Swings

At 6,035 feet elevation, we regularly see 50-degree temperature swings in a single day. These rapid changes stress concrete joints and can accelerate the settling process in already-vulnerable slabs.

This makes proper winter protection essential for any freshly leveled surface.

What to Expect: Timeline, Disruption, and Results

Homeowners are often surprised by how fast and non-disruptive the process is.

Typical Project Timeline

Project Type	Duration	Holes Drilled
Single sidewalk panel	15 to 30 minutes	1 to 2
Driveway section	1 to 2 hours	4 to 8
Full patio	1 to 3 hours	6 to 12
Garage floor	2 to 4 hours	8 to 15
Pool deck	3 to 5 hours	10 to 20

Disruption Level

Noise: The drilling is the loudest part. It sounds like a large drill and lasts a few minutes per hole.
Mess: Minimal. Some concrete dust from drilling and possibly a small amount of material overflow at the holes.
Landscaping: Equipment stays on the hard surface. Your lawn and garden beds remain untouched.
Utilities: No digging, no trenching, no disruption to underground lines.

Compare that to a full replacement, which involves jackhammering, hauling away debris, re-grading, forming, pouring, and a 7-day cure time. The difference in disruption is dramatic.

Is Concrete Leveling Worth It?

From a pure cost perspective, leveling typically runs 50% to 70% less than tearing out and replacing the same slab.

The math for a typical 2-car driveway:

Leveling cost: $800 to $2,200
Replacement cost: $4,000 to $8,000
Savings: $2,000 to $6,000

Beyond the cost savings, leveling preserves your existing concrete (which has already cured and hardened for years), avoids the environmental waste of demolition, and can be completed in hours instead of days.

For a full pricing breakdown by project type, see our complete cost guide for Colorado Springs.

The Bottom Line

The concrete leveling process is straightforward: drill small holes, inject material, raise the slab, patch the holes, and move on with your day.

The technology has been used successfully for decades, and modern materials have only improved the longevity and precision of the results.

If your concrete is sinking but still structurally sound, leveling is almost certainly the most cost-effective, least disruptive path to a flat, safe surface.

The key is working with a contractor who understands your specific soil conditions, can identify why the settling occurred, and uses the right method for your situation.

If you are seeing signs that your concrete needs leveling, contact us for a free assessment. We will walk your property, explain exactly what is happening, and give you an honest recommendation on whether leveling is the right solution.