Mudjacking vs Polyurethane Foam Concrete Leveling: Which Is Better?

Also called slab jacking, slabjacking, and foam jacking. Here is the honest comparison.

For most sunken concrete in the Yakima Valley, polyurethane foam is the better choice over traditional mudjacking. Foam lifts the slab through small holes, weighs a fraction of what mudjacking's cement slurry does, cures in about 15 minutes, and does not wash out over time. Mudjacking still works and costs less up front, but it is heavier, cures slowly, and tends to settle again as the slurry erodes. If you want a repair that lasts and is usable the same day, foam is the method to ask for.

What is mudjacking?

Mudjacking is the older method of raising sunken concrete, and it works by pumping a heavy slurry underneath the slab. A contractor drills large holes, usually one to two inches across, then pumps a mix of cement, water, and soil or sand through them until the slab lifts back into place. It has been used for decades and it does lift concrete. The trade-offs are weight, cure time, and staying power: the slurry is heavy, it can take one to three days to cure, and because it is soil and cement based, water can erode it over time and let the slab settle again.

What is polyurethane foam leveling?

Polyurethane foam leveling lifts the slab by injecting an expanding foam through small holes instead of a heavy slurry. We drill penny-sized ports, about five-eighths of an inch, and inject a two-part polyurethane foam that expands to fill the voids, firm up the loose soil, and raise the slab back to grade. It is the method Level Best Northwest uses, with Eco-Rise foam. The foam is lightweight, so it does not add stress to soil that is already struggling to hold the slab, and it is hydrophobic, so it does not absorb water or break down.

Ellensburg before image of uneven sidewalk fixed with Polyurethane Foam

What are the real differences between the two?

The methods differ most in weight, hole size, cure time, and how well the repair holds up.

Here is the side by side:

Factor	Mudjacking	Polyurethane foam
Material	Cement and soil slurry	Expanding polyurethane foam
Weight	Heavy, adds load to weak soil	Lightweight, minimal load
Hole size	1 to 2 inches	About 5/8 inch
Cure time	1 to 3 days	About 15 minutes
Water resistance	Can wash out and erode	Waterproof, does not break down
Longevity	Shorter; may resettle	Longer lasting
Up-front cost	Lower	Higher

The short version: mudjacking is cheaper on day one, and foam costs less over the life of the repair because it holds.

Why does soil in Central Washington favor foam?

Foam holds up better here because our soils shift with water and freeze-thaw, which is exactly what erodes a mudjacking slurry. Central Washington ground moves with irrigation, poor drainage, and the freeze-thaw cycles we get every winter. Those are the same forces that wash cement slurry out from under a slab and let it drop again. Because polyurethane foam is waterproof and lightweight, it stands up to those conditions instead of being undone by them. Poor drainage is the most common reason concrete sinks here in the first place, which we cover in why concrete sinks and how drainage causes it.

How we lift concrete with foam

Our process is built to lift the slab precisely and get you back on it the same day:

1. Measure the settlement. Owner Merle sets a dial gauge across the slab to read the exact drop before lifting, so the panel comes up flush without overshooting and cracking it.

2. Drill small ports. We drill five-eighths-inch holes through the settled areas.

3. Inject the foam. Eco-Rise foam is pumped through the ports, expands to fill voids and firm up the soil, and lifts the slab back to grade.

4. Patch and finish. The foam cures in about 15 minutes, the holes are patched, and the surface is ready to use the same day.

   
   

We use this on driveways, sidewalks, patios, and garage floors across the Yakima Valley and Ellensburg. On a recent Ellensburg sidewalk with a settled joint, we measured the drop, lifted the panel with foam, and had the walkway back in use that afternoon with no demolition.

Ellensburg after image of uneven sidewalk fixed with Polyurethane Foam

When is mudjacking still worth considering?

Mudjacking can make sense when up-front cost is the deciding factor and the slab is not exposed to much water. It is a real method, not a scam, and for a low-traffic slab on stable, dry ground where budget is tight, it can do the job for less money today. What we would not recommend it for is anything exposed to drainage, irrigation, or freeze-thaw, because that is where the slurry erodes and you end up paying twice. When we look at your concrete, we will tell you straight which method fits, and if replacement is the honest answer instead of either one, we will tell you that too. Our guide to concrete leveling versus replacement walks through that line.

Get a free estimate

If you have a sunken driveway, sidewalk, or patio and you are weighing your options, the first step is a look and an honest recommendation. Level Best Northwest provides free estimates for concrete leveling across the Yakima Valley, Tri-Cities, and Ellensburg. Call (509) 796-0658 or send us a message.

Frequently asked questions

Is mudjacking or foam better for a driveway?

Foam is usually the better choice for a driveway. It is lightweight, cures in about 15 minutes so you can drive on it the same day, and resists the water and freeze-thaw that cause driveways to settle again.

Does polyurethane foam leveling last longer than mudjacking?

Yes. Foam does not absorb water or break down, so it holds the slab in place longer, while a mudjacking slurry can erode over time and let the concrete resettle.

Is foam leveling more expensive than mudjacking?

Foam usually costs more up front than mudjacking. Over the life of the repair it often costs less, because it lasts longer and is less likely to need redoing.

How big are the holes for foam leveling?

About five-eighths of an inch, roughly the size of a penny. They are patched after the lift and are barely noticeable. Mudjacking holes are larger, usually one to two inches.

Do you offer mudjacking?

Level Best Northwest uses polyurethane foam leveling, because it holds up better in Central Washington soils. If you are deciding between methods, we are happy to explain the trade-offs for your specific slab.

By Merle Brovont, owner of Level Best Northwest, a family-owned, owner-operated concrete repair company serving the Yakima Valley, Ellensburg, and the Tri-Cities. Last updated: 8/11/26