Tag: slab leveling

Wouldn’t it be wonderful if driveways perpetually flat and smooth, pristine surfaces on which to drive or walk or play? Unfortunately that is not reality. Many will eventually be faced with a cracked and sinking driveway.

And while driveways will inevitably, in time, require replacement, your goal should be to avoid that solution as long as possible. It is invasive. It is time-consuming. And it is very expensive.

The Problem With Sinking Driveway Slabs

When a driveway begins to sink and settle, the problems are twofold. The first are those that are the direct result of the sinking.

Ideally, your driveway slab should be basically level with the sidewalk and with the entrance to your garage. If your driveway slab begins to sink at one end, this is no longer the case. This can both pose a tripping hazard and increase the wear and tear on your tires.

Depending on how the driveway sinks, it also could affect drainage off of it. Ideally, your driveway won’t drain water toward your home. If it begins to sink in a way that it does, that can cause more significant problems for your home.

The second set of problems caused by a concrete slab sinking is the effect that it has on the concrete itself. If the entire slab sinks uniformly, your might have minimal issues in this regard. Unfortunately that is rarely the case. If the soil underneath supports some areas of the driveway better than others, it is going to place the slab under stress. Eventually, that stress will likely cause cracking. The longer the slab is under that stress, the worse the cracking issues are likely to get.

A Better Way to Repair a Cracked & Sinking Driveway

Unless the concrete is too far gone to be saved, a better option than tearing it all out and starting from scratch is to lift the sunken concrete back to its original level.

This will not magically fix the cracks. It will, however, remove the tripping hazards that cracks with elevation changes bring. It will also remove the stress on the concrete that can lead to more cracking by properly supporting the slab from below.

How Polyjacking Works

At Foundations on the Level, we use polyurethane foam concrete leveling, also known as polyjacking. After determining where the concrete needs to be lifted, we will drill one or more small holes roughly the size of a dime through the concrete slab. An expanding polyurethane foam solution is then injected through the hole into the soil underneath the slab.

The solution flows into the weak spots in the soil and then starts to expand, hydraulically lifting the concrete upward as it does so. By closely monitoring the process, we can precisely level your driveway slab.

Why Polyjacking Over Mudjacking?

Polyjacking holds several key advantages over the old concrete lifting standby of mudjacking.

1. Smaller holes: While the size of mudjacking holes vary, they are often at least twice as large as those made for polyjacking. That makes the mudjacking holes more difficult to repair in a way that both doesn’t cause harm to the slab and doesn’t stick out like a sore thumb on the driveway.
2. Faster cure time: With mudjacking, you usually can’t use your driveway for 24 hours after it is completed. With polyjacking, that time is 15 minutes.
3. Water resistant: The polyurethane foam doesn’t break down in the presence of water or the chemicals found in soil. This makes it basically erosion-proof. The same can’t be said of cement slurry used in mudjacking, which can break down over time.
4. Light-weight: The mudjacking slurry is heavy, which can further weigh down the soil. Polyurethane foam, on the other hand, is much lighter, removing that potential problem.

Need to Level Your Driveway in San Diego or Orange County? Give Foundations on the Level a Call

If you live in Southern California and your driveway is sinking and you want more information on what concrete leveling entails, contact us today at Foundations on the Level.

You’ve noticed that portions of your sidewalk or driveway (or porch, or pool deck, or any other concrete slab around your house) has started to sink. The slab is cracking, and the elevation change on either side of the crack is posing a tripping hazard. But why is your slab sinking?

The root of the problem likely lies in the soil beneath it, including when the root of the problem is literally a root.

Causes of Sinking Concrete Slabs

Soil Not Properly Compacted

Concrete is heavy. If the soil beneath the sinking slab isn’t properly compacted, it won’t be strong enough to support the weight of the concrete without the slab sinking.

Erosion

Erosion can create voids under concrete slabs. Those voids then act as weak points, with those portions of the slab sinking. This differential settlement causes cracking and tripping hazards.

Shrink-Swell Cycle

Some soils, especially clay, have significant shrink/swell cycles. Depending on the condition of the soil when the concrete was laid, the soil shrinking as it dries could lead to settlement or the soil expanding when it is wet could lead to heaving.

Tree Roots

As trees grow, the roots grow, and sometimes grow under concrete slabs. During the growing stage, the roots are more likely to cause heaving than settlement or sinking. Mature trees, depending upon soil type, can draw enough water in through their roots to dry out the surrounding soil. The shrinkage from this can cause settlement in some cases. If a tree dies or it cut down, the decomposing roots can create voids or patches of poorly compacted soil, causing the slab to sink.

How We Repair Sinking Slabs

If the sinking slab is caused by poorly compacted soil or voids beneath the slab, we have the solution: concrete lifting with polyurethane foam. We pump the expanding foam beneath the slab. As it expands, the foam fills any subsurface voids and compacts the surrounding soil from within. It then hydraulically lifts the slab back to level from underneath.

Read more about concrete leveling.

Contact Us To Learn More About Our Concrete Leveling Services in Southern California

Foundations on the Level proudly serves San Diego and Orange counties in California. If you live within our service area and would like to learn more about how we can lift your sunken concrete slab, contact us today.