Sinking Foundation Repair Seguin, TX.

The Guadalupe River clay is doing the sinking

Homes near the Guadalupe corridor in Seguin sit on deep alluvial clay laid down over centuries of flood-plain sedimentation. It's a different animal from the shallow, rocky ground farther west toward the Balcones Escarpment, thick, highly plastic, and slow to drain. Soil scientists call it high-plasticity clay, and in the river bottomlands plasticity index values routinely run past 40. That number is the tell: at that plasticity, the soil changes volume dramatically as moisture comes and goes.

So the ground breathes with the seasons. Wet months it swells and pushes up. Then a Central Texas summer drought pulls moisture from the perimeter, shrinkage cracks open through the clay, and the soil that was holding up the slab edge contracts. The edge drops. That single motion is behind the stepped cracks in your brick mortar, the doors that catch at the top corner, and the floor that tilts toward one end of the house, real differential movement, not cosmetic.

Why the repair has to go deeper than the movement

The layer that expands and shrinks with the weather is called the active zone, and in Seguin's Guadalupe clay profiles it commonly reaches 10 to 15 feet below grade. That depth is the whole reason so many past repairs don't hold. A pressed-concrete pier that terminates inside the active zone is still sitting in soil that moves, so it moves too, and the corner drops again a few seasons later.

GroundLock takes a different path. We drive galvanized steel piers hydraulically, section by section, past the active zone into the competent bearing strata below. Each pier advances until it hits the resistance benchmark set in the engineer's written plan for that soil profile, and only then takes the load. That's a permanent load path down to strata that don't join the seasonal shrink-swell.

Because settlement here is a moisture story as much as a structural one, lifting alone is only half the fix. Where drainage or irrigation is feeding the movement, we address the water too, managing what the clay drinks is what keeps the corner from dropping a second time. Our foundation repair approach is built around that pairing.

How a Seguin repair actually runs

Reading the warning signs on a Seguin house

A few things tell you whether the clay is pulling a corner down, and how urgent it's getting:

• Stair-step mortar cracks climbing through the brick joints point to differential settlement, the slab edge is dropping.
• Horizontal cracks in the brick face are a different signal: lateral soil pressure or heave, which changes the repair scope.
• Doors dragging at the top corner and floors sloping toward the front or back mean the movement has reached the structure, not just the veneer.
• Under about three-quarters of an inch of movement is usually cosmetic; beyond that, plumbing, window frames, and roof load paths start taking stress.
• Drip emitters set 18 to 24 inches off the slab can oversaturate the active zone and cause heave that gets misread as settlement nearby.
• Flat or negative grade at the perimeter is a consistent culprit, aim for at least a 6-inch drop over the first 10 feet.

Seguin sinking-foundation questions, answered