Concrete Levelling – The Ultimate Guide to Fixing Sunken Surfaces

Uneven concrete is more than just an eyesore. It’s a tripping hazard, a maintenance headache, and a potential liability. Sunken concrete can create serious problems if left unchecked regardless of whether it’s your driveway, sidewalk, patio, or garage floor.

Over time, soil erosion, weather changes, and poor installation can cause concrete slabs to settle unevenly. This not only looks bad but can also lead to water pooling, cracks, and structural damage. The longer you wait, the worse it gets—and the more expensive the fix.

In this article, you will learn:

• Why concrete levelling is essential for safety and property value.
• The most effective methods for concrete levelling.
• How to choose a reliable concrete levelling service.

Let’s dive into the details of why concrete levelling is crucial and how it works.

What Causes Concrete to Sink?

Concrete slabs don’t just sink overnight. It’s a slow process caused by natural soil movement, weather changes, and improper installation. If you’ve noticed uneven surfaces around your residential property, understanding the root causes can help prevent further damage.

Soil Shifting and Erosion

Over time, the ground beneath your concrete slab moves. Water runoff, poor drainage, or tree roots pulling moisture from the soil can create voids under the slab. Without support, the concrete settles, which creates an uneven surface.

Freeze-Thaw Cycles

In places like Canada, where winter temperatures fluctuate, the ground expands and contracts repeatedly. This movement weakens the soil, which leads to sinking and cracking.

Poor Installation & Soil Compaction

If the soil wasn’t properly compacted before the concrete was poured, it can settle unevenly over time. This is especially common in new residential areas. Proper planning and material selection are crucial in preventing these issues.

Water Drainage Issues

Excess water can wash away soil from under your concrete slab and leave unsupported gaps. In fact, proper drainage is key to preventing sinking regardless of whether it’s a patio, driveway, or walkway.

Concrete Levelling vs. Replacement: Which One is Better?

If your concrete slab has started to sink, you might wonder whether to replace it entirely or opt for concrete levelling. While replacement may seem like a long-term solution, it’s often unnecessary and more expensive.

Cost Comparison

Concrete levelling is typically 50-70% cheaper than a full replacement. Removing old slabs, preparing the ground, and pouring new concrete requires more labor, time, and materials, which makes it a costly choice.

Time Efficiency

Levelling can be done in a few hours, whereas replacing a concrete slab takes several days due to demolition, curing, and finishing.

Environmental Impact

Concrete replacement generates waste. Levelling techniques like polylevel foam injection reuse existing materials, which makes it an eco-friendly alternative.

Durability

Modern methods, such as polyurethane foam injection, offer long-lasting results. Unlike traditional repairs, the foam expands to fill voids, which prevents future sinking.

For most residential and commercial areas, levelling is the smarter, more cost-effective solution—especially when using Canadian concrete levelling methods like polylevell foam.

Methods of Concrete Levelling – Pros & Cons

There are several ways to lift and stabilize sunken concrete slabs, each with its own advantages and drawbacks. Choosing the right method depends on the type of project, budget, and long-term durability.

Mudjacking (Slab Jacking)

Mudjacking involves pumping a thick cement slurry beneath a concrete slab to raise it. This method is affordable and works well for large areas like driveways and parking lots. Since the material is heavier, it can handle heavier loads compared to other levelling techniques. However, the added weight can sometimes lead to future settling. Another drawback is the larger holes that must be drilled into the slab, which can weaken its structure over time.

Polyurethane Foam Injection (Polylevel Foam)

A more modern approach is polyurethane foam injection, often referred to as polylevel foam. This technique involves injecting a lightweight, expanding foam beneath the slab to lift and stabilize it. One of its biggest advantages is its fast curing time—most surfaces are ready to use within minutes. 

The foam is also moisture-resistant, which makes it an excellent choice for preventing erosion and future settling. Unlike mudjacking, it requires smaller drill holes, which helps preserve the slab’s appearance. The only downside is that it tends to be slightly more expensive, and it requires trained professionals with specialized equipment to apply it correctly.

Grout Pumping

Grout pumping is another technique used to stabilize concrete slabs, but it is mostly suited for industrial and commercial projects rather than residential applications. A cement-based grout mixture is injected under the slab, reinforcing weak soil conditions. 

While effective for large-scale projects, its heavy material makes it impractical for most residential driveways or sidewalks. Additionally, the process can be costlier than polylevel foam when used for smaller repairs.

How to Choose the Right Concrete Levelling Contractor

Not all concrete levelling services are the same. Choosing the right contractor ensures you get a long-lasting, high-quality repair that won’t need fixing again in a few years.

Start by looking at experience and reviews. A reputable contractor should have a history of successful projects, with positive customer feedback and real before-and-after photos. Companies that specialize in polyurethane foam injection often produce the most durable results, so check if they use modern materials instead of outdated methods like mudjacking.

Next, consider warranty and guarantees. A quality repair should last for years, and trusted companies offer multi-year warranties to back up their work. If a contractor doesn’t provide a guarantee, it might be a red flag.

Lastly, find a contractor with local knowledge. In areas like Lethbridge, where freeze-thaw cycles impact soil stability, experienced professionals will know how to prevent future sinking. A good contractor ensures the concrete stays levell for years to come.

Fix Your Concrete Today

Sunken concrete doesn’t just look bad but is also a safety hazard and a costly problem waiting to get worse. Concrete levelling is an affordable, quick, and durable solution that can restore your driveway, patio, or walkway in just a few hours.

Don’t wait until the damage spreads. 

Sunny South Inc. specializes in professional concrete lifting and levelling in Calgary and uses advanced polyurethane foam injection for lasting results.

Get a FREE quote today and make your concrete surfaces safe and functional again.

Click here to request your free consultation.