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Sinking Concrete? What’s Really Occurring

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Ugly cracks in your basement or garage floor could mean that your concrete slab is sinking. If the soil beneath the concrete cannot support the heavy weight of the slab, the concrete will not be level and sink unevenly. 

Why Does Concrete Sink?

Shrinking or Compacted Soil

Georgia’s soil is expansive, which means that it contains a significant amount of clay or silt. As the soil absorbs water, it will expand and push against your concrete. When it dries out and shrinks, however, it will settle and compact. This settling under your concrete slab means that the slab is no longer supported and it will sink in places. Sinking concrete is made obvious by cracks in several places throughout the slab.

Soil Washout

Weather can also have an extreme effect on the health of your concrete slab. Georgia’s ever-changing climate can bring heavy rains and winter thaws, which causes the expansive soil under your concrete slab to erode away. Pretty soon, the concrete won’t have enough support and will become uneven. Additionally, the soil could wash away and leave a void underneath the concrete. Without the proper support, your concrete will start to sink or cave in.

AquaGuard Can Help

Sinking concrete doesn’t have to be a threat to your home’s safety and value. AquaGuard can help with our PolyRenewal™ concrete leveling and stabilization! Our priority is making sure you and your family are safe, and that your concrete slab is stable. Our concrete repair solutions are quick, effective, and minimally invasive. We can bring your concrete slab back to level in no time at all!

If you’re looking for contracting experts in Atlanta, Athens, Rome, Marietta, or surrounding areas, look no further than AquaGuard Foundation Solutions. We are the premier foundation repair and waterproofing professionals! 

Concrete sidewalk

Concrete sinks because it’s heavy! When the soils underneath a concrete slab are unable to support its weight, the slab will sink. This is called slab settlement, and this uneven concrete condition frequently happens on Atlanta driveways, sidewalks, walkways, garage floors, and foundations in the area and all over the country.  


If soils support part of the concrete slab, and other sections do not, then the unsupported pieces may crack away from the other section and result in unlevel concrete.


Concrete’s Worst Enemy

Moisture is concrete’s worst enemy. It seeps into the pores of untreated concrete, and when temperatures drop, the trapped moisture expands as it turns into ice.

Concrete may be durable, but it’s not indestructible. The expansion from excess moisture destroys the pores and weakens the concrete, resulting in concrete slabs that pit and flake.

Primary Causes of Sinking Outdoor Concrete:

Soil Shrinkage, Compaction & Settling


Different types of soil have different load-bearing capacities. When a soil’s load-bearing capacity is exceeded, the soil will compact and settle.
It’s also possible for the soil beneath a slab to settle and compact of its own accord. Soil that contains large amounts of clay and/or silt, as much of Georgia’s soil does, will shrink substantially when it dries out.

As the soil compacts underneath a concrete slab, the unsupported slab will sink as well, usually cracking in one or more areas as a result.

Washout Of Soils

The soil underneath your driveway, that patio, or concrete steps is also highly susceptible to Georgia’s ever-changing weather and climate changes. Just as compaction or shrinkage can occur during periods of drought, during heavy rains, or when the ground thaws out after freezing during winter, that same soil can wash out and erode. Once this occurs, your soil can provide little to no support for the heavy concrete that rests on top of it.

As water moves underneath your concrete slabs, it can wash away the soil that’s supporting the weight of the overlying concrete. As this happens, a void is created underneath. Over time, with nothing to support it, your concrete slab will begin to crack, sink, or cave in. Suddenly, you’ve got a significant concrete settlement problem, safety hazard, and potential loss of resale value.


The Permanent Solution to Fix Sunken Concrete

In previous years, mudjacking has been the traditional method for Atlanta sinking concrete repair – but is it your best option? Mudjacking involves injecting a slurry of cement and soil beneath the concrete slab. However, if the soil or fill upon which the slab was installed is weak or poorly compacted, the mudjacked slab will more than likely go right back to sinking, making it a temporary solution to lifting your concrete.


At AquaGuard, we have a better solution: PolyRenewal™® injection. This Atlanta sinking concrete repair process takes the original concept of mudjacking and combines it with modern knowledge and technology. It’s lightweight, provides a greater lifting power than mudjacking, and requires little to no waiting for it to cure. 

*Disclaimer: “Concrete leveling” means the process by which cracked, uneven concrete is stabilized, and in many cases lifted, by means of PolyRenewal™ polyurethane foam. AquaGuard Foundation Solutions does not guarantee that PolyRenewal™ can make your concrete perfectly level.

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