A neighbor stops by and says, “Hey, did you know your sidewalk out front is a trip hazard?”
You look down, and sure enough—one slab sits higher than the next. Now you can’t unsee it. Every time you carry in groceries or have guests over, that uneven slab nags at you.
So you start searching for a fix, and two terms keep coming up: mudjacking and polyurethane foam lifting. Both raise sunken concrete. But they’re not the same, and the difference shows up in how your concrete looks and holds up for years afterward.
I’m Travis, owner of TK Concrete Lifting. Here’s a straight comparison so you can decide what’s right for your home.
Table of Contents:
TL;DR: Mudjacking pumps a heavy cement slurry under your slab through large holes. Foam lifting injects a lightweight polyurethane foam through much smaller holes. Foam is cleaner, cures in about 30 minutes, and won’t wash out when it gets wet. Mudjacking can cost less up front, but for most Colorado homeowners, foam is the better long-term fix.
What Is Mudjacking?
Mudjacking (also called slabjacking) is the older way to raise sunken concrete. Contractors have used it for decades, and plenty still do.
Here’s how it works:
- Holes are drilled through the slab—typically 1 to 2 inches across.
- A slurry of soil or sand, water, and cement is pumped underneath.
- The slurry fills the empty space and pushes the slab back up.
- The holes are patched with cement.
The basic method is simple, and it often costs less up front. But it comes with trade-offs:
- It’s heavy. The slurry weighs roughly 100 pounds per cubic foot. That’s a lot of extra weight on soil that already let your slab sink once.
- The holes are big. Even after patching, they’re easy to spot.
- It’s messy. Mixing and pumping slurry takes bigger equipment and leaves more cleanup.
- It can wash out. Slurry can soak up water and erode over time, which lets the slab settle again.
What Is Polyurethane Foam Lifting?
Foam lifting (polyurethane injection) is the modern alternative—and it’s the only method we use at TK Concrete Lifting.
- Drill: We drill small holes, about the size of a dime.
- Inject: High-density polyurethane foam goes under the slab.
- Lift: The foam expands, fills voids, and gently raises the slab back into place.
- Cure: In about 30 minutes, the foam hardens into a strong, water-resistant base.
It’s not just for homes, either. State transportation departments have tested injected polyurethane to raise highway and bridge approach slabs—for example, this Oregon DOT research report. If it can hold up under highway traffic, your driveway is in good hands.
Why Foam Wins: 4 Big Differences
1. Smaller Holes
Mudjacking holes are usually 1–2 inches wide. Foam injection holes are closer to 5/8 of an inch. In that same Oregon DOT study, the foam holes were about 16 mm, compared with 50–75 mm for conventional grout. Once we patch them, they’re hard to find.
2. Less Mess
Our equipment is compact and fits in a standard driveway. There’s no slurry to mix on your lawn, no wet spills to clean up, and no torn-up flowerbeds.
3. Ready in About 30 Minutes
Foam cures fast. In most cases, you can walk, drive, or park on your concrete about 30 minutes after we finish. Mudjacked slabs can need several hours before they’re ready.
4. Water-Resistant and Lightweight
Cured foam doesn’t absorb water or wash away, so rain and snowmelt won’t erode it. And because it weighs only a few pounds per cubic foot, it doesn’t load extra weight onto weak soil.
Side-by-Side Comparison
| Feature | Mudjacking | Foam Lifting |
|---|---|---|
| Hole size | About 1–2 inches | About 5/8 inch (dime-sized) |
| Material weight | Heavy slurry (~100 lbs/cu ft) | Lightweight foam (a few lbs/cu ft) |
| Ready to use | Often several hours | About 30 minutes |
| Water | Can absorb water and erode | Water-resistant; won’t wash out |
| Mess | Slurry mixing, bigger equipment | Compact equipment, minimal cleanup |
| Up-front cost | Often lower | Often higher |
| Long-term value | May need redoing sooner | Built to last; fewer repeat repairs |
What About Cost?
This is usually the first question I get. Mudjacking often costs less on the day of the job. But if the slurry settles or washes out and the slab drops again, you’re paying for the same repair twice.
Foam usually costs more up front, but it’s far less likely to need a do-over. Most of our residential jobs land between $800 and $2,500, depending on the size of the slab and how far it has sunk. Either way, lifting is a fraction of the cost of tearing out and replacing concrete.
The only way to know for sure is to look at your slab. Our assessments are free, and I’ll give you a straight answer on what it will cost and what result to expect.
Built for Colorado Soil
Colorado is tough on concrete. The Colorado Geological Survey calls expansive, clay-rich soil the state’s most significant geologic hazard. Those clays swell when they get wet and shrink when they dry out, which is why cracked and heaved sidewalks, patios, and driveways are so common here.
Add our freeze–thaw cycles, and water becomes the enemy. It seeps under a slab, freezes, expands, and leaves voids behind when it thaws. Because foam doesn’t absorb water or wash out, it holds up much better in these conditions than a cement slurry.
One more tip: no repair method can fully beat poor drainage. Keeping downspouts and grading pointed away from your slab is the best way to protect your concrete. Here’s more on how leveling helps with drainage.
When Mudjacking Might Still Make Sense
Is mudjacking always the wrong choice? Not necessarily. It may be good enough if:
- You need a short-term fix, like leveling a slab before selling.
- It’s a low-traffic area, like a shed pad or a rarely used back path.
- Lowest up-front cost is your only priority.
We only do foam lifting, so I’ll be honest with you: if you’re planning to stay in your home, foam is almost always worth the difference.
Mudjacking vs. Foam FAQ
Q: Is mudjacking the same as slabjacking?
A: The terms are often used interchangeably for pumping material under a slab to raise it. Some people also use “slabjacking” for foam lifting. Either way, what matters is what’s being injected: a cement slurry or polyurethane foam. Learn more about our slab jacking service.
Q: Do you offer mudjacking?
A: No. We use polyurethane foam on every job because it’s cleaner, faster, and holds up better in Colorado’s soil and weather.
Q: Which one looks better afterward?
A: Foam. The holes are much smaller and barely noticeable once patched.
Q: Can foam-lifted concrete handle my truck?
A: Yes. Cured lifting foam has high compressive strength and supports vehicles without trouble. You can usually drive on it about 30 minutes after we finish.
Q: Is foam lifting covered by a warranty?
A: Yes. Every lift we do is backed by our 2-year workmanship warranty, as long as water is kept draining away from the slab.
Have more questions? Check out our foam lifting FAQ.
The Bottom Line
If you want the cheapest short-term fix, mudjacking may do the job. But if you want a repair that’s clean, fast, and built for Colorado’s soil and climate, polyurethane foam lifting is the clear winner.
Picture pulling into a smooth, level driveway. Walking a sidewalk with no trip hazards. Enjoying a patio without puddles. That’s what foam lifting delivers.
👉 Schedule your free assessment
📞 Or call (719) 285-4056
📍 Serving Cañon City, Colorado Springs, Pueblo, and surrounding Central Colorado communities. See all service areas.