Wondering about mudjacking vs. polylevel for leveling concrete slabs? If so, you’ve landed on the right page because that’s what we’re going to talk about in this short article. Both mudjacking and polylevel are methods for repairing uneven concrete slabs like sidewalks, driveways, pool decks, and patios.
But which one is better? And why? How are they similar, and how are they different? In this article, we’re going to answer all these questions and more.
Why Concrete Slabs Become Unlevel
Concrete slabs become uneven for various reasons, including:
- Soil erosion – Poor drainage along with erosion-prone soil can lead to the formation of voids under the slab. If the slab sinks into these voids, it will become uneven.
- Expansive soil under the slab – Soil with a lot of clay is called “expansive” because it expands when it soaks up moisture and shrinks as it dries out. This swelling-shrinking cycle creates movement under the slab, which can cause it to become uneven eventually.
- The soil wasn’t adequately compacted before the slab was poured – Soil needs to be correctly tamped down before the slab is poured on top of it. If this isn’t done, the slab will sink into the soil and become unlevel.
- Drought – Voids may form if the soil dries out under the slab. When the slab sinks into the voids, it will become uneven.
- Tree roots have invaded the soil under the slab – We’ve probably all seen examples of uneven slabs – sidewalks, usually – caused by invasive tree roots.
What is Concrete Lifting?
Concrete lifting involves injecting material under the uneven slab to lift and level it. Concrete lifting is used on sidewalks, driveways, pool decks, patios, and more. Anywhere there’s an uneven concrete slab, concrete lifting can usually fix the problem.
For more information, see Frequently Asked Questions About Concrete Leveling.
Mudjacking vs. Polylevel
Traditionally, concrete lifting was done via mudjacking. This involved injecting a slurry – containing cement, soil, sand, and other materials – under the slab to lift and level it. Today, most concrete lifting jobs are done using polylevel (also referred to as polyurethane foam injection, polyfoam, polyjacking, slab jacking, poly leveling, etc.). Polylevel uses waterproof polyurethane foam to lift the slab back into place.
Mudjacking is an older technique for raising an uneven concrete slab. The procedure involves drilling several holes in the slab (2-3 inches in diameter) and injecting the cement slurry under the slab through the holes. The slurry spreads out under the concrete, filling the voids and raising the slab. The holes are then patched with a compound that matches the color of the concrete.
The cons of mudjacking include the messy nature of the cement slurry, the time it takes before you can use the slab again (2-3 days to cure), and the fact that the cement slurry is heavy. It places weight on soil that might already be having trouble holding up the slab. This could cause the slab to become unlevel again. Also, since the cement slurry contains sand and soil, it could erode. Finally, the holes used in mudjacking are larger than those used for polylevel. This can affect the aesthetics of the final result.
Today, polylevel is the most common way to lift and level an uneven concrete slab. Polylevel uses strong but very lightweight polyurethane foam to lift the slab. Because polylevel is waterproof, it won’t erode. Because it cures fast, most polylevel concrete lifting jobs only take about three hours tops, and then the slab is ready for use again. Although the foam used in polylevel is synthetic, it won’t leech harmful chemicals into the soil.
The polylevel process for concrete lifting is as follows:
- Dime-sized holes are drilled into the uneven slab.
- Polylevel foam is injected under the slab.
- The foam rapidly expands to fill the voids and raise the slab.
- The holes are patched with a compound that matches the color of the slab.
The only real con to polylevel is the cost. It’s more expensive than mudjacking. However, you’ll find contractors out there who disagree with us. Here’s our answer to their concerns: Concrete Lifting Foam Beats Mudjacking Hands Down For Fixing Uneven Slabs.
The Cost Of Mudjacking vs. Polylevel
Polylevel is more expensive than mudjacking but less expensive than digging up the uneven slab and pouring a new one.
The cost of concrete lifting depends on your geographical location, the chosen lifting method (mudjacking vs. polylevel), and the size of the slab that needs leveling because this determines how much lifting material – polylevel foam or cement slurry – is required. Contact a foundation repair contractor in your area who does concrete lifting and ask for an inspection and estimate.
What About Replacing The Concrete?
Tearing up and replacing an uneven slab is expensive and time-consuming. Freshly poured concrete takes time to dry and harden. While you’re waiting, you won’t be able to use the slab. However, replacing the concrete might be necessary if the slab is severely damaged.
If you have an uneven slab that needs concrete leveling and you’re in our service area in Nebraska, Iowa, Kansas, and Missouri, contact us today for an inspection and repair estimate.