Why Your Concrete Driveway is Sinking and How Concrete Leveling Provides the Permanent Fix

A cracked or uneven driveway is more than just an eyesore; it’s a serious trip hazard that diminishes your property’s curb appeal and value. While concrete is known for its durability, it is entirely dependent on the stability of the soil beneath it. When driveway slabs begin to sink, tilt, or crack, it’s a clear sign that the supporting ground has been compromised.

Understanding why your concrete driveway is sinking is the first step toward finding a reliable, long-term concrete leveling solution. Fortunately, modern concrete leveling and lifting techniques offer an affordable, non-destructive alternative to the costly and disruptive process of completely tearing out and replacing your concrete.

The Root Causes of Sinking Driveways

Concrete slabs don’t sink because they are too heavy; they sink because of voids that form in the soil base directly underneath them. These voids allow the heavy concrete slab to settle, leading to uneven surfaces, dangerous tripping hazards, and unsightly cracks. The problems that lead to these voids are typically related to water and soil composition.

Soil Erosion and Washout: One of the most common culprits behind sinking concrete is water. Poor drainage around your home or even continuous heavy rainfall can cause the soil beneath your driveway to erode. When water seeps into the ground through cracks or along the edge of the slab, it washes away the supporting fill material, creating hollow pockets—or voids—that the concrete slab simply can’t bridge. As a result, the concrete slab eventually settles into this newly created empty space.

Soil Consolidation and Settlement: Even without erosion, the soil can lose volume and stability over time, causing the concrete to settle. When driveways are installed, the subgrade soil may not have been compacted properly. Over the months and years following installation, the soil will naturally consolidate and settle. Additionally, expansive clay soils that saturate and swell with moisture, only to shrink dramatically when dry, create continuous movement that shifts the entire structure above them. This movement allows the concrete to become unlevel as it “settles over time”.

Geographical and Historic Factors: In specific geographic areas, sinking concrete can be caused by profound underlying issues. For instance, some regions are prone to Mine Subsidence, where abandoned underground mines collapse, causing the earth above to shift and settle dramatically. This geological instability can lead to significant foundation and concrete problems, demonstrating the extreme importance of repairing the unstable soil beneath the surface.

The Solution: Concrete Leveling and Lifting

Traditionally, the only way to fix a sinking driveway was to demolish the slab, haul away the heavy waste, and pour an entirely new section. This process is messy, expensive, and time-consuming. Today, the preferred method is concrete raising and leveling, a process that offers a cost-effective and efficient way to repair your concrete without the need for demolition.

Concrete leveling, often referred to as slabjacking, involves restoring the concrete slab back to its original position by floating it back up. The average cost for this repair ranges significantly, typically falling between $300 to $2,500, making it a budget-friendly option compared to replacement. The speed of the process is another major benefit, as it can often be completed in a single day, and the area can be used almost immediately.

Advanced Methods for Leveling Concrete

While the traditional slabjacking procedure involves drilling holes in the concrete and pumping a sand, cement, or other additive mixture beneath the slab, modern innovations have led to superior, longer-lasting methods that focus not just on lifting the concrete but on stabilizing the soil beneath it.

Deep Foamjection™: The Soil Stabilization Upgrade

A true upgrade to standard concrete raising is Deep Foamjection™. This process uses environmentally safe polyurethane foam, which is hydro-insensitive and does not leak nasty chemicals into the ground. Rather than just lifting the surface, Deep Foamjection™ actively repairs the unstable soil beneath concrete.

The specialized foam is injected into voids and fissures deep below the surface, stabilizing the subgrade and preventing future settlement. This method ensures that the concrete is not only level but that the underlying cause of the sinking—the unstable soil—is permanently addressed.

HydroFoam: Specialized Water Resilience

For specific concrete jobs where water is a persistent issue, such as pool decks, retaining walls, or sea walls, an even more specialized product is required. HydroFoam is a hydro-insensitive polyurethane foam designed specifically for these wet environments. It is engineered to last forever, staying strong and maintaining its shape without deterioration, even when constantly exposed to water. Like Deep Foamjection™, HydroFoam is environmentally friendly and provides a durable, permanent fix for concrete that suffers from washout and persistent moisture problems.

By opting for advanced concrete leveling and lifting techniques like polyurethane foam injection, you can quickly and safely level concrete that has settled over time. This process restores your driveway to a safe and attractive condition, ensuring your investment is protected for years to come.