Your sidewalk has tripping hazards between sections due to unevenness. Your driveway holds water in one area because the slab is not sloping at the correct angle any longer. *Sigh* You’ve got some problems with your outdoor concrete surfaces and are wondering if concrete slab jacking might work for you, but first, you need to find out what it is.
At Anchor Foundation Repair, we offer one form of concrete slab jacking (called mud jacking) and can tell you about this general term, as well as the various methods available to homeowners for concrete repair of this kind.
This article will define the term concrete slab jacking, cover the basic process of how it works, explain the two methods available, and provide cost estimates for this kind of repair service. Get ready for Concrete Slab Jacking 101!
What is Concrete Slab Jacking and How Does It Work?
Concrete slab jacking is a general term that refers to a couple of types of concrete repair method that raises and returns concrete slabs to their original position. Concrete slab jacking works to raise the sunken slab back to its original elevation and slope by injecting material underneath the sunken surface.
Slab jacking goes by many different generic names and there doesn’t seem to be a universal term that everyone recognizes. You can also hear this type of repair referred to as:
- Slab jacking
- Concrete leveling
- Concrete raising
- Concrete lifting
- Repairing uneven concrete
All the terms above mean the same thing as concrete slab jacking.
Side Note: I’d like to *inject* some commentary on one of these terms: concrete leveling is kind of a misleading term. We really can’t say that your concrete surface is going to be 100% mathematically level when a concrete slab jacking repair is done.
Even if your concrete *looks* to be level, most exterior concrete surfaces are not precisely level when they are made. Outdoor concrete slabs of any kind are subtly (or not so subtly) sloped on purpose, so that water can drain off of them when it rains. – end side note –
Second Side Note: Although some methods of foundation repair for slab homes can be considered a type of “concrete slab jacking” it’s not a term used in relation to foundations. So when you think of slab jacking – think of *outside stuff* rather than *under home* stuff.
When You Need Slab Jacking
Over time, concrete surfaces resting on the ground can begin to settle and sink, or slope in ways that you don’t want them to go. This is especially true in geographic areas with expansive clay soil like we have here in Texas and many other states in the US.
As long as your concrete surface is still in good shape, then it’s a good candidate for some type of slab jacking.
How Slab Jacking Is Done
Concrete slab jacking is done by drilling holes in the concrete and injecting a filler material underneath the slab to be raised. The material slowly fills up space under the surface and then lifts the concrete slab up from below to put it back in its original and intended position.
Repair contractors that do slab jacking will work in a controlled manner to keep the flowing material from overfilling the space or lifting too much. They can be precise and carefully ease the slab back where it’s supposed to be. The injected material will then dry and harden to secure the new position.
What Is Concrete Slab Jacking Good For?
Typically, slab jacking works for shallow exterior concrete slab types, like sidewalks, patios, and driveways in residential applications. Concrete slab jacking can also be used for concrete roadways and parking lots.
Slab jacking works well for sections of concrete that are still in good condition that have simply sunk and settled into an undesired position. Slab jacking is not good for concrete that is badly cracked all over or severely degraded or crumbling.
Concrete slab jacking only works right if the concrete slab is still intact and the only holes in it are the holes that are created to complete the process. Otherwise, the material that is injected underneath would be forced out of the other holes and the process would not work.
How Much Does Concrete Slab Jacking Cost?
Costs for concrete slab jacking can range anywhere from $800 for a small project involving one or two affected concrete panels, to $8,000 for an extensive project that includes an entire large driveway.
Total costs depend on the number of slab panels that need to be raised, how long the job takes, and on your chosen method or type of slab jacking. Yes! There is more than one way to jack your slab and it’s by using different materials to do it.
Common Methods of Concrete Slab Jacking: Poly and Mud
There are two primary methods of concrete slab jacking: polyjacking and mud jacking. The main difference between these two methods is the fill material that is used.
Polyjacking uses a chemical polyurethane expanding foam for the injection material. Polyurethane is a common construction material that is used in all kinds of things from roofing materials to insulation to foam for your couch!
The poly material flows like canned shaving foam when it comes out of the injection nozzle. Poly expands and then hardens into a lightweight but rigid styrofoam-like substance that is very strong on the horizontal and can lift heavy things.
Polyjacking can sometimes be used for raising a home foundation that has settled under the interior and is also used for outdoor concrete surfaces. Polyjacking also has a variety of names, some are more like “brand names” and some are generic terms. You might hear:
- Polyfoam injection
- I bet there’s more that I can’t think of right now
All the above terms mean the same thing as polyjacking. I don’t know why everyone has to have 500 different names for this stuff but here we are . . .
It’s not just *mud* but more of a mud-like mixture that is used for mud jacking to raise concrete surfaces. Mud jacking uses a flowing mixture of cement, topsoil, and water called slurry to complete the concrete lifting process.
The slurry mixture is liquid, like pancake batter, and flows easily. When the slurry dries, it hardens into a dense sandstone-like substance that is also very strong on the horizontal and can bear considerable weight.
Fortunately, there are not 20 different terms for mud jacking in the world of concrete repair. It’s not the prettiest-sounding term, but hey at least there’s only one . . .
What About Pros and Cons for Concrete Slab Jacking Methods?
Nothing gets by you, does it? Now that you know there are different types of concrete slab jacking, I’m sure you want to know more about the pros and cons of each method.
At Anchor Foundation Repair, we want homeowners to be informed about all the options available, even if it’s a service we don’t provide (we only do mud jacking, not polyjacking). After doing business in the Brazos Valley for over 35+ years, we find that what’s best for you is also what’s best for us.
In the spirit of fairness, transparency, and education, we have a pros and cons article all about Mud Jacking vs. Polyjacking Concrete Repair that will give you a full rundown on the costs, materials, and features – including the pros and cons – of these two methods of concrete slab jacking.