Core service

Sinking Foundation Repair.

Settlement you can see and feel rarely stops on its own. We measure the drop for free to ±0.01 in. and stabilize it on galvanized steel piers driven past the active clay.

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A foundation almost never sinks evenly. One corner drops while the far end of the house sits untouched, and the difference is what you feel underfoot, a floor that tilts toward the kitchen, a front door that suddenly drags on its strike, a hairline that creeps up the brick a little more each August. In the San Antonio, Austin corridor, that uneven settlement is the soil doing exactly what Central Texas soil does when the moisture under your slab stops being uniform.

Left alone, it compounds. A quarter-inch drop a year sounds harmless until you stack ten of them and the slab edge is two and a half inches out of plane, with the interior partitions cracking to follow. The good news is that the fix is well understood and the diagnosis is free: a precise elevation survey shows the exact shape of the deflection, and steel piers carry the load down to ground that does not move with the seasons.

What's actually pulling your slab down

East of the Balcones Escarpment, most of this corridor sits on Blackland Prairie Houston Black clay, a soil with a plasticity index that routinely runs between 40 and 60. That number is the whole story: high-PI clay swells when it's wet and shrinks hard when it's dry, and a long Central Texas summer pulls moisture out of the ground unevenly depending on where your trees, roof runoff, and afternoon sun fall. The side that dries out the fastest is the side that drops.

The depth that matters is the active zone, the band of soil that still swells and shrinks with each wet-and-dry cycle. Here it usually runs eight to fourteen feet below grade, and a thirsty mature tree or a chronic irrigation leak can push it deeper. Any repair that stops short of the bottom of that zone is just anchoring to soil that will keep heaving. That's why pier depth, not pier count, is the decision that determines whether a fix lasts.

West of the escarpment the mechanism flips. Thin soils sit over Edwards limestone, and instead of a whole perimeter settling, an isolated point can punch down where a solution cavity or fractured rock gives way beneath it. Same symptoms in your living room, very different cause under the slab, which is exactly why we measure before we propose anything.

How GroundLock stops the sinking

Free elevation survey

We grid your whole footprint to ±0.01 in. (1/64 in.) so we can see the deflection bowl, corner drop, mid-span sag, or a multi-directional tilt, and place every pier where it actually belongs.

Drive galvanized steel piers to refusal

Piers are pushed hydraulically past the active clay into competent strata, dense clay shale under the Blackland or the limestone shelf out west, and stopped at hydraulic refusal rather than a guessed depth.

Lift back toward level in sequence

Once every pier reaches refusal we transfer the load onto steel and recover elevation in small, sequenced increments so no section gets jolted into new cracking.

Re-survey, document, and warranty

A post-lift survey confirms the correction against the starting grid, and that record backs a lifetime warranty that transfers to the next owner.

Why galvanized steel, and not bare metal

Blackland clays around here often carry elevated sulfate, which chews through unprotected steel over time. The hot-dip zinc coating acts as a sacrificial barrier rated for decades in that soil, so the support staying under your house outlives the warranty paperwork.

Most projects land between $4,500 and $14,000 depending on how many piers the survey calls for, financing is available, and nearly every home stays occupied while the crew works from the exterior.

Questions from Central Texas homeowners

Why is only the back corner of my house dropping while the rest seems fine?

Because the moisture under a slab is never uniform. A tree, a downspout, or a sunnier exposure can dry out the clay on one side faster, so that corner loses support while the rest stays put. We pier the affected section down to stable ground and lift it back toward level.

If I just wait, will it actually get worse, or hold where it is?

It compounds. The clay keeps cycling with every dry summer and wet spring, so a slow drop today is usually a faster one in a few years, with more interior damage and more piers needed. Catching it earlier almost always means a smaller, cheaper job.

How deep do the piers have to go to actually hold in this soil?

Past the bottom of the active zone, typically eight to fourteen feet here, and into competent material, which is dense clay shale on the Blackland side or the limestone shelf west of the escarpment. We drive to hydraulic refusal rather than a fixed depth, since rock depth varies across a single lot.

Will the cracks in my drywall and brick close back up after the lift?

Many tighten as the slab returns toward level, but we never promise a crack will vanish. Cosmetic crack, drywall, and paint repair is a separate finishing step we can include or hand off to your painter.

Do you fix what's causing the movement, or just jack the house up?

Both, where it makes sense. We stabilize on piers and then address the drainage or moisture driving the settlement, because lifting without managing the water just resets the clock on the same problem.

Should I be watering around the slab during a drought, and how?

In a hard Central Texas drought, yes. A soaker hose about 12 to 18 inches out from the perimeter, run evenly all the way around, keeps the clay from pulling away and settling. Steady and consistent beats heavy and occasional. Uniform moisture is the goal, not saturation.

How long is the crew at my house, and do we have to move out?

Most homes are done in one to three days on site, and you stay in the home for nearly every job. You'll hear equipment during the day, but crews work from the exterior and access points and tidy up before they leave.

Schedule

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