Originally posted 1/9/2020, updated 3/8/2021
We’ve all seen it happen- or had it happen to us. The unfortunate party guest walks across the patio, with a drink in one hand and a plate of food in the other. Their shoe catches on a crack or uneven area in the concrete, they trip, and presto! Everything they were carrying is now something everyone is wearing.
Party fouls aside, uneven concrete can be a significant problem for a homeowner. Cracks in walkways aren’t just unattractive; they’re trip hazards that can become a liability.
There are a variety of ways to repair damaged concrete slabs; in this article, we’re going to review slabjacking, its costs, and how it compares to other options available. Since our founding in 1996, Acculevel has repaired thousands of concrete slabs. In our experience, slabjacking is the most reliable and longest-lasting method.
When slabjacking technology was introduced to the market, we researched it at length before deciding to transition away from mudjacking in 2015. Because we have considerable experience with both methods, we’re able to give you a detailed analysis based on extensive first-hand experience. It’s our intention to help you make the best decision for your home.
An Overview of Slabjacking
Slabjacking is a form of concrete leveling. Small holes are drilled through the slab, and a fill material is injected through these holes into the space below the slab. As this void is filled, the injected material lifts the slab up. The most advanced slabjacking uses polyurethane foam as the injection material. The foam solidifies within minutes, allowing someone to walk on a lifted walkway or park on a lifted driveway almost immediately.
Want to see the process for yourself? We have a demo for you to view!
The polyurethane foam is environmentally safe for use in yards, as well as around children and pets. It does not shift, erode, or decay like other fill materials, and is often a permanent fix.
These photos were taken by an Acculevel crew member: before & after slabjacking a section of driveway. The crack was filled with a polyurethane sealant.
Alternatives to Slabjacking
Similar to slabjacking, mudjacking also drills through the slab to inject a filler material. However, as the name indicates, the fill is a type of “mud” that is usually a diluted solution of concrete or limestone. Mudjacking is less expensive than slabjacking; it normally costs 40-50% less, but cannot be used as quickly. Since it’s a water-based mixture, it has to cure (dry) over a number of hours. And because it uses water in the mix, it is still susceptible to the effects of weather and can decay, break apart, or erode.
Another option is to have the damaged concrete torn out and re-poured. This is more expensive than slabjacking; the cost for demolition and replacement can cost twice as much as slabjacking.
Replacing the slab also takes longer than either concrete lifting method. New concrete needs to cure, which can take days or weeks, depending on the location and weather conditions. If you replace the concrete but don’t address the cause of the original issue, this new slab may crack and shift just as the old one did. We provide more information on the causes of concrete shifting in another article.
However, there are occasions when replacing the slab is the best choice. If the slab is broken into multiple pieces, severely cracked, or deteriorated, lifting may not be possible or feasible. A good contractor will be able to evaluate the concrete and recommend the best course of action for you.
Limitations of Slabjacking
Concrete lifting- either by mudjacking or slabjacking- does have limits.
The concrete slab must be entirely made of concrete. The lifting process does not work for any other type of material- brick pavers, tiles, asphalt, etc.
Slabjacking cannot be done if the ground is frozen. Mudjacking cannot be done once air temperatures are below freezing since water is used in the mixture.
What Does Slabjacking Cost?
The job minimum for this process is $2000 (price includes labor and materials). At Acculevel, we define the “job site” as your entire property. This means that if you have multiple places around your home that need repair, we will combine all of these to meet the minimum cost. For example, you may have a patio in your backyard, and two steps leading to your front porch that both need leveling. This wouldn’t be a $4000 minimum job, because both sections are on the same property.
You can estimate your potential slabjacking costs yourself, if you’d like! Generally speaking, the cost is $10 per square foot. If you need a quick refresher course on calculating square footage, Nolan can explain:
Additional Costs to Consider
In some instances, the concrete slab is eroded or undermined, with a large void below it. If this is the case, you should also evaluate where your guttering downspouts or sump pump lines are draining on the property. If you have a broken pipe or drain, these can also be the source of the issue. Repairing plumbing, extending downspouts, or rerouting drainage lines can resolve the situation, and allow the lifting repair to be a more permanent solution.
You also need to be aware of ‘additional fill charges’ that can result from larger voids. If there is significant erosion or settling, it takes more fill material than normal to complete the repair. If this is the case, you should discuss this with the contractor before doing the job, to establish what your budget limitations are and if lifting is the best fit for you.
Have Concrete that Needs Repair? The Next Step:
Find an experienced specialty company that provides the service you prefer, and make an appointment. Before you sign a contract for any service, you should always verify the company is reputable, insured, and accredited by the Better Business Bureau.
We have a guide to questions you should ask a contractor that we hope you’ll use. Our goal with this document is to help you determine not only which company to hire, but to also help you steer clear or any person who engages in questionable or ethical business practices.
If you live in Indiana or the surrounding states, contact Acculevel. We offer free estimates and will schedule an appointment with one of our experienced project managers. They will evaluate your home and areas of concern, then recommend the best course of action for you to keep your home strong and healthy.