When concrete slabs sink, crack, or shift, property owners generally have two repair options available: polyjacking services and mudjacking. Both methods lift sunken concrete back to its original position without full slab replacement, but they work in different ways and produce different results. Understanding how each method functions, what materials are used, and which situations call for which approach helps property owners make informed decisions when concrete problems arise.
Mudjacking is the older of the two methods and has been used in construction repair since the early twentieth century. The process involves drilling holes into the sunken concrete slab, then pumping a mixture of water, soil, and cement beneath the surface. This slurry fills the voids under the slab and physically lifts it back toward the desired elevation as pressure builds.
Once the slab reaches the correct height, the drilled holes are patched, and the area is left to cure. The slurry hardens over time and provides a base of support beneath the concrete.
Mudjacking is a well-established technique that many contractors across the country offer. The equipment required is relatively common, and the materials used, primarily soil and cement, are widely available and inexpensive.
The slurry mixture used in mudjacking is heavy. A cubic foot of the material can weigh between 100 and 150 pounds. When this dense material is pumped beneath a slab, it adds significant load to the soil that is already struggling to support the concrete above it. Over time, the added weight can cause the soil to compress further, and the slab may sink again.
The slurry also retains moisture. In areas where soil conditions involve clay or where freeze and thaw cycles occur regularly, moisture retention in the fill material can cause expansion and contraction beneath the slab, leading to further movement.
Mudjacking also requires larger drill holes, typically one to two inches in diameter, which are more visible after patching. The curing time for the slurry means the surface usually cannot be used for at least 24 hours after the repair.
Polyjacking services use a different material entirely. Instead of a soil and cement slurry, the process involves injecting expanding polyurethane foam beneath the slab. Contractors drill small holes into the concrete, typically around five-eighths of an inch in diameter, and insert an injection port. The two-part polyurethane material is then pumped through the port and expands as it cures, filling voids and lifting the slab.
The foam expands rapidly and reaches approximately 90 per cent of its full strength within 15 minutes of injection. This allows the repaired surface to be used again within a short time after the work is complete.
Polyurethane foam is significantly lighter than mudjacking slurry. A cubic foot of the foam material weighs around two to four pounds, compared to the 100 to 150 pounds of mudjacking slurry. This weight difference means polyjacking services place far less additional load on the existing soil.
The properties of polyurethane foam make it well-suited for slab-lifting work in several conditions where mudjacking performs less reliably.
Polyurethane foam does not absorb water. Once cured, it maintains its structure regardless of moisture conditions in the surrounding soil. This makes polyjacking services a more stable long-term option in areas with wet climates, poor drainage, or soils that shift seasonally.
The foam also fills irregular void shapes more thoroughly than slurry. Because it expands, it reaches into gaps and cavities that a pumped liquid might not reach completely. This complete fill provides more consistent support across the underside of the slab.
The smaller drill holes required for polyjacking services are less visible once patched and cause less disturbance to the existing concrete surface.
Mudjacking adds substantial weight beneath a slab. This matters most on properties where the soil has already shown signs of compression or poor load-bearing capacity. Polyjacking services add minimal weight, which reduces the chance of future settling caused by the repair material itself.
Mudjacking slurry takes hours to cure, and the area must remain undisturbed during that period. Polyjacking foam cures quickly, and the repaired surface can typically handle foot traffic or light vehicle use within 30 minutes to an hour.
Mudjacking requires larger holes that leave more visible patches after the repair. Polyjacking services use smaller holes that are easier to patch cleanly, which matters more on finished surfaces like patios, pool decks, and decorative concrete.
Because polyurethane foam resists moisture and adds less load to the soil, polyjacking services generally last longer than mudjacking repairs in comparable conditions. Mudjacking can be a durable repair in stable, dry soil, but the material's weight and moisture retention create conditions for repeat settling over time.
Mudjacking works well on large concrete areas where material cost is a concern and conditions are stable. Polyjacking services are better suited for areas with active drainage issues, clay soils, freeze and thaw exposure, or surfaces where appearance after repair matters.
The best repair method depends on the specific conditions of the property. Soil type, drainage patterns, climate, the size of the affected area, and how the surface is used all affect which approach will perform better over time.
On a basic residential sidewalk in a dry climate with stable soil, mudjacking may provide an adequate repair at a lower material cost. On a garage floor, driveway, pool deck, or any surface near a structure where soil conditions are variable, polyjacking services offer a more reliable and longer-lasting result.
Property owners who have experienced repeated concrete settling on the same surface after mudjacking often find that polyjacking services produce a more durable outcome because the lighter material does not compound the soil load problem that caused the original settling.
Contractors who specialise in concrete lifting, such as Lift It Pro, evaluate both the visible symptoms and the underlying soil conditions before recommending a method. This assessment matters because the right repair for one property may not be the right repair for another, even when the concrete damage looks similar from the surface.
Mudjacking and polyjacking services both lift sunken concrete without full replacement, but they differ in material, weight, cure time, hole size, moisture resistance, and long-term performance. Mudjacking uses a heavy soil and cement slurry that cures slowly and retains moisture. Polyjacking services use lightweight polyurethane foam that cures quickly, resists water, and adds minimal load to the existing soil. For properties where drainage, soil stability, or surface appearance is a concern, polyjacking services are generally the more dependable choice. A qualified contractor can assess the site conditions and recommend the method best suited to the specific repair.