Methods
Polyjacking vs Mudjacking
Both methods raise a settled slab by injecting material beneath it. They differ in what gets injected, and those differences drive hole size, weight, cure time and how each behaves on a given site. Neither is universally better.
Side-by-side
Characteristics commonly reported for each method. Specifics vary by product, provider and site — treat this as orientation, not specification.
| Polyjacking (polyurethane foam) | Mudjacking (cement slurry) | |
|---|---|---|
| Injected material | Two-part polyurethane that expands after injection | A cement-based slurry of sand, cement and water (mixes vary) |
| Injection holes | Small-diameter holes, commonly around penny-sized | Larger holes, commonly around 1–2 inches |
| Weight added | Light relative to the volume filled | Heavier — a consideration where the soil is weak |
| Set / cure | Sets quickly; return-to-use is usually the same day | Needs longer to cure before full loading |
| Void filling behaviour | Expands into irregular spaces | Fills by flowing and being pumped into place |
| Access needs | Rig and hose; small equipment footprint | Mixing and pumping equipment on site |
| Cost pattern | Usually the higher unit cost of the two | Usually the lower unit cost of the two |
| Visual result | Small patched holes | Larger patched holes, more visible on finished surfaces |
Where polyjacking tends to fit better
- Visible surfaces where small holes matter — walkways, patios, finished floors.
- Situations where added weight over weak soil is a concern.
- Areas that need to be back in use quickly, including commercial walkways.
- Irregular voids that a flowing material may not reach evenly.
- Interior slabs where mixing equipment is impractical.
Where mudjacking remains a reasonable choice
- Larger exterior slabs where hole size is less important.
- Filling substantial spaces where a lower-cost material is used in volume.
- Budget-driven projects on utilitarian surfaces.
- Providers with the equipment and experience to do it well locally.
Mudjacking is a long-standing method, not an obsolete one. Being told it is always the wrong choice is a signal to get a second opinion.
What actually decides the outcome
The method matters less than three other things: whether the slab is a sound candidate for lifting at all, whether the space beneath it is properly filled, and whether the cause — usually water — is addressed. A well-executed mudjacking job on a slab with the drainage fixed will outlast a poorly executed foam job with a downspout still discharging beside it.
See how long concrete leveling lasts for why the cause dominates.
Claims to be cautious about
Homeowner questions
Which one is cheaper?
Mudjacking generally carries a lower unit cost. Whether a project is cheaper overall also depends on the volume of material needed and the access, so a cheaper method does not always mean a cheaper quote.
Does foam last longer than slurry?
Both materials are durable once in place. Longevity is driven mainly by whether the underlying cause of settlement continues, not by the choice between them.
Can I ask for one method specifically?
You can, and it is reasonable to ask why a provider prefers the other. If the explanation is site-specific, that is a good sign; if it is generic marketing, ask more questions.
Keep going
Get method proposals for your slab
Describe the surface and the problem. Providers can explain which method they would propose for your specific situation and why.