Why San Antonio Slab Foundations Move
San Antonio sits on some of the most active clay in Texas. Here’s exactly why local slabs move — and how we stabilize them.
Houston Black clay
The dark, high-plasticity clay across much of San Antonio swells and shrinks dramatically with the seasons, dropping slab edges and cracking brick.
The drought driver
San Antonio’s frequent droughts shrink that clay hard, which is why damage peaks in late summer.
The fix here
Steel piers reach below the active clay; pair with drainage to keep it permanent.
- Houston Black clay drives big seasonal movement.
- Drought makes damage peak in late summer.
- Steel piers plus drainage make the fix last.
Not sure how serious it is?
Get a free, ±⅛-inch elevation survey and a written, engineer-backed plan — no pressure.
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