Concrete Leveling for San Antonio Flatwork

Small ports are drilled through the settled slab, typically around the diameter of a coin. High-density polyurethane foam is injected through those ports. The foam expands underneath the concrete, first filling the voids that allowed the slab to drop and then, as it continues to expand, applying upward pressure that lifts the slab. Lifting is controlled by managing injection volume and monitoring the slab as it moves. The ports are then patched flush.

Polyjacking is the polyurethane foam method described above. Mudjacking, the older approach, pumps a cementitious slurry through larger holes to achieve the same lift. Mudjacking uses larger ports, adds considerable weight to the subgrade, and takes longer to cure. Polyurethane is lighter, uses smaller ports, and cures faster. Mudjacking still has applications, particularly on large voids, but for most residential flatwork polyurethane is the more practical choice.

Structurally sound concrete that has settled as a unit. That covers uneven driveway slabs, settled patios, sunken sidewalks, pool deck leveling, and concrete steps and landings. The test is whether the slab is intact enough to be lifted as a piece. A slab in two or three large pieces can often still be lifted. A slab that has broken into many fragments cannot.

When the concrete itself has failed. Heavy spalling where the surface is delaminating, extensive map cracking, exposed and corroded reinforcement, or a slab broken into many pieces all point to replacement rather than lifting. Foam can raise concrete but it cannot restore concrete that has lost its integrity. We will tell you when that is the situation rather than lifting something that will fail again shortly.

Usually because the material supporting it moved or left. Common causes in this area are soil compaction over time under poorly prepared subgrade, subgrade erosion and washout from water tracking under the slab, expansive clay shrinking during dry periods, and settlement of fill placed during construction. Identifying the cause matters, because lifting a slab over an active washout is a short-term result.

Polyurethane cures quickly. Most residential surfaces are usable within hours of injection, and in many cases much sooner. The exact figure depends on the product used, ambient temperature, and the volume injected, so we confirm it per product and project rather than quoting a single number. This is one of the main practical advantages over mudjacking.

The holes are small and they are patched flush with a cementitious material on completion. On an older weathered driveway the patches will be visible on close inspection because new material does not match aged concrete. On a broom-finished surface they blend reasonably well. If appearance is a priority, say so and we will plan port placement with that in mind.

Sometimes, and it depends on the crack. A slab with one or two clean cracks can usually be lifted, though the sections may move slightly differently and the crack may need sealing afterwards. A slab with extensive cracking is likely to move as fragments rather than as a unit, which produces a poor result. Slab thickness and condition are assessed before any commitment is made.

Not by itself, and it can affect it. Flatwork is usually sloped deliberately to shed water away from a structure. Lifting a slab changes that geometry, so drainage slope preservation is part of the planning rather than an afterthought. Where water pooling was the original cause, correcting the drainage is a separate piece of work that belongs in the conversation.

They are different services addressing different structures. Flatwork sits on the ground and carries no building load, so lifting it is a surface-level correction. A house foundation carries the structure and is repaired with piers reaching a load-bearing stratum. Settled flatwork does not mean the house foundation has moved, and a sound house foundation does not mean the driveway is fine. They are assessed separately.

It tracks the area being lifted, the height of the lift, the volume of foam required to fill voids, and access for the equipment. A single sunken sidewalk panel and a full driveway approach are very different jobs. Because void volume is not fully known until injection begins, our written quote states the basis for pricing and how any variance is handled rather than presenting a figure that quietly changes.

Usually, when the concrete is sound. Lifting avoids demolition, disposal, new material, forming, pouring, and cure time, and it avoids the disruption of having a driveway out of service for days. When the concrete has genuinely failed, replacement is the better value because lifting compromised concrete does not produce a durable result. Our guide comparing leveling with replacement sets out the criteria.

Pool deck leveling is a common application, and the settled panel around a pool is often exactly the sort of trip hazard worth addressing. The considerations are the same: the concrete needs to be sound, the void needs to be fillable, and the finished slope needs to keep water moving away from the pool structure rather than toward it. Coping and tile edges need care during the lift.