When the ground under a concrete slab erodes away, it can cause a lot of problems. Homes with basements usually have the most problems, but voids can impact driveways, patios, sidewalks, and more. The erosion causes air pockets or voids to develop under the concrete slab, taking support away from the surface.
Causes of Voids
There are several different reasons that a void can occur beneath your concrete. Most of the time, it isn’t due to erosion, but other factors. Some issues are fast, others can take years to cause problems.
Soil consolidation occurs over time. This occurs when loose soil under the concrete consolidates or sifts down. If the soil is not properly prepared by being tamped down, this can occur. When the soil consolidates, a void can form over time.
Settlement is a natural occurrence that happens over time. It can occur with new construction or with a property that is a hundred years old. It all depends on the type of soil and weather patterns. Heavy rains or flooding can cause the soil to settle faster than normal. If the settling soil is in a large enough area, it can allow erosion to occur. Settling soil sets the table for a problem, erosion just makes it worse.
If water doesn’t drain correctly or there is new landscaping or other additions to the property, erosion can start after years with no problems. The water will run freely, washing out the soil and creating a void under the concrete. The bigger the void, the more damage that can occur.
Solutions for Voids Under Your Concrete
You don’t have to tear up your concrete to fix the problem of having a void. The best solution is polyjacking. A high-density polyurethane foam is injected through small holes into the voids. The foam expands, filling the void and sealing any cracks on the underside of the slab. The foam will not wash away and the slab is usable shortly after the foam is injected. Mudjacking is an alternative, but the sand-based grout can be washed away or not completely fill the void and you’re back to square one.
Call the Voided Concrete experts at Nick Gress Foundations at 636-219-1967 or 314-409-1497 to learn more or get a free estimate.