Voids Under Your Concrete? Fix the Problem Before It Gets Worse

Void filling is the process of filling empty spaces underneath your concrete slab to restore proper support. Over time, soil can wash away or settle, leaving gaps that cause the concrete to sink or crack. We use expanding polyurethane foam that flows into these voids, fills them completely, and hardens to create a stable base. This not only stops further movement but also prepares the slab for lifting if needed. You can learn more about how the full process works here: Concrete Leveling Process

In many cases, you actually need both. Void filling addresses the root problem—the empty space under your concrete—while lifting brings the slab back to a level position. If you only lift without filling the voids, the problem can come back over time. That’s why we often combine void filling with full concrete leveling to make sure the repair lasts. Learn more about lifting services here: Residential Concrete Leveling

Most void filling jobs can be completed in just a few hours, depending on the size of the area and how much material is needed. One of the biggest advantages of polyurethane foam is how quickly it sets. In most cases, your concrete is ready to use immediately after the work is done, so there’s little to no downtime for your home or business.

Void filling significantly reduces the chances of future settling because it removes the empty spaces that cause movement in the first place. The foam also helps stabilize loose soil and adds support under the slab. While no repair can completely prevent all future ground movement, this method provides a long-lasting solution that performs much better than temporary fixes.

Voids usually form due to water erosion, soil compaction, or poor drainage. Water can wash away the soil beneath your slab, especially around driveways, sidewalks, and foundations. Over time, this creates empty pockets that weaken support. Freeze-thaw cycles and heavy loads can also contribute to the problem by shifting or compressing the soil unevenly.

Yes, in most cases polyurethane foam is a better option. It’s lightweight, which means it won’t add extra stress to already weak soil. It also expands to fill even small gaps and creates a tight seal that resists water intrusion. Compared to traditional mudjacking, foam is cleaner, faster, and provides more precise results. You can compare both methods here: Poly Leveling vs Mudjacking

Void filling helps prevent cracks from getting worse by stabilizing the slab underneath. However, it doesn’t fully repair visible cracks on the surface. For that, we may recommend sealing the joints or cracks to protect against water damage and further wear. Learn more here: Concrete Caulking

Some signs include sinking or uneven slabs, hollow sounds when walking on concrete, visible gaps under edges, or water pooling in certain areas. Even if you’re not sure, we can inspect the area and determine if void filling is needed as part of the solution.

Getting a quote is quick and easy. You don’t even need to be home—we offer virtual estimates where you can send photos of the problem area. From there, we’ll review your situation and recommend the best solution. Get started here: Contact Us