Sunken concrete is more than an eyesore. Cracks, uneven surfaces, pooling water, gaps beneath a slab, and unexpected trip hazards can make driveways, walkways, patios, or commercial concrete areas difficult and unsafe to use. For property owners searching for polyjacking in Calgary, the bigger concern is often whether the slab can be repaired without the disruption and expense of removing and replacing the concrete. Understanding the warning signs, what causes slabs to settle, and when lifting is an appropriate solution can help you address the problem before it becomes more difficult or costly to repair.
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What Is Polyjacking and How Does It Work?
Polyjacking — short for polyurethane foam jacking — is a concrete lifting method that raises and stabilizes settled slabs by injecting high-density expanding foam beneath them. It’s one of the most widely used modern alternatives to traditional mudjacking, and for good reason: the process is faster, less invasive, and delivers results that hold up well over time.
The process begins with small holes drilled through the concrete — typically around 5/8 of an inch in diameter, which is considerably smaller than the holes required by older lifting methods. Next, a specialized, high-density liquid polyurethane foam is injected through these holes into the empty space beneath the surface. As the material expands, it fills gaps and voids in the underlying soil while creating pressure that gradually lifts the slab back toward its intended position. Once the desired level is reached, the foam hardens and provides support beneath the concrete. Because the injection holes are relatively small and the material cures quickly, polyjacking can often be completed with less disruption than removing and replacing the existing slab.
Warning Signs Your Concrete Slab May Need Polyjacking
Concrete settlement rarely happens without visible clues. The changes may start small, but they can become more noticeable as the ground beneath the slab continues to shift or lose support. Knowing what to look for can help property owners decide when a concrete problem deserves professional attention.
Common warning signs include:
- Sunken or uneven concrete: One part of the slab sits noticeably lower than the surrounding surface, creating an uneven walking or driving area.
- Cracks that are getting worse: New cracks or cracks that gradually widen can indicate movement beneath the slab. Not every crack means the concrete needs lifting, but changes over time are worth investigating.
- Pooling water: Low areas can collect rain or melting snow instead of allowing water to drain properly. This can contribute to further soil movement beneath the slab.
- Gaps beneath the concrete: If you can see daylight or an obvious gap along the edge of a slab, part of the underlying support may have been lost.
- Trip hazards: A raised edge or uneven transition between two sections of concrete can create a hazard for people walking across the area.
- Slabs pulling away from nearby surfaces: Gaps between a concrete slab and a foundation, step, curb, or other structure can be another sign that the slab has shifted.
These problems can appear on driveways, sidewalks, patios, garage floors, warehouse floors, and other concrete surfaces. If the slab is still largely intact but has settled or lost support underneath, polyjacking in Calgary may be one option for restoring its position and improving the support below it.
Why Calgary’s Climate Makes These Problems Worse
The local environment is incredibly tough on outdoor surfaces. For property owners, understanding the weather is a big part of knowing why you might need polyjacking in Calgary. The main factor is the freeze-thaw cycle. Throughout the winter and spring, moisture in the ground freezes and expands, pushing upward against the concrete. When the weather warms up and the ice melts, the soil shrinks back down. Over multiple seasons, this constant heaving and settling loosens the dirt and creates empty pockets — one of the most common reasons property owners find themselves researching polyjacking in Calgary as a repair solution.
The region also has a high concentration of clay in its soil. Clay acts like a sponge—it swells up when it absorbs moisture and shrinks tightly during long dry spells. This severe shrinking physically pulls the soil away from the bottom of your concrete slab. Once that gap forms, the heavy concrete has nothing to rest on, and gravity eventually pulls the slab downward into the void.
When Polyjacking Is the Right Solution — and When It Isn’t
Polyjacking is an effective solution for a specific type of concrete problem — and being honest about when it works well and when it doesn’t helps property owners make better decisions about their repair options.
Polyjacking works well when:
The concrete slab itself is structurally intact — meaning it hasn’t fractured into multiple pieces or deteriorated to the point of crumbling — but has settled because the soil beneath it has shifted, eroded, or compacted unevenly. In these situations, the slab is essentially sound; it just needs its support restored. Polyjacking in Calgary is particularly well suited to driveways, sidewalks, patios, garage floors, pool decks, and steps where the concrete has sunk but remains in one piece. It’s also a strong choice when minimizing disruption is a priority — the small injection holes, fast cure time, and same-day return to service make it far less disruptive than full concrete replacement.
Polyjacking may not be appropriate when:
The concrete has deteriorated significantly — with extensive cracking, large sections broken into multiple fragments, surface spalling, or structural weakness that would prevent it from holding together during the lifting process. In these cases, the concrete itself needs to be replaced rather than simply lifted. Polyjacking also isn’t a solution for problems caused by ongoing structural issues — such as a failing foundation or significant plumbing leaks beneath the slab — that will continue to erode the soil support after the repair is completed. If the underlying cause isn’t addressed alongside the lifting, the settlement is likely to return.
The value of a professional assessment
The most reliable way to determine whether polyjacking is the right solution for a specific slab is to have a qualified contractor assess the concrete in person. A professional can evaluate the condition of the slab, identify the likely cause of the settlement, and recommend the most appropriate repair — whether that’s polyjacking, a combination of void filling and lifting, or replacement. A contractor who recommends polyjacking without first examining the slab isn’t providing advice you should rely on.
Conclusion
Leaving sunken concrete untreated rarely ends well. What starts as a minor trip hazard or a small puddle can quickly escalate into severe foundation drainage issues and liability risks for your property. However, dealing with these problems does not mean you have to endure the massive expense, noise, and mess of tearing out your entire driveway or patio. By acting early and choosing professional polyjacking in Calgary, you can permanently stabilize the soil and lift your concrete back to a safe, level position in a matter of hours.
If you are tired of looking at sinking slabs and want to avoid the disruption of a full replacement, exploring your repair options is the best next step. To understand more about how this advanced foam injection process can save you time and money compared to traditional methods, read our detailed breakdown on the benefits of void filling, or contact the Ener-Spray team for a professional assessment of your concrete.