Spotting the signs from the driveway is step one. Confirming what's happening under the slab takes measurement, and on Alvin's expansive clay that measurement step is what keeps a repair from becoming a guess. A real diagnosis starts well before anyone talks about piers.
Why a real measurement matters on this clay
The clay under Alvin (Beaumont, Bacliff, Lake Charles, and Bernard series) swells and shrinks seasonally, which means a house can look like it has "settled" when the real story is a temporary seasonal dip that will partly recover after the next rain. Telling the difference between a seasonal wobble and real, permanent settlement is exactly what a floor-elevation survey and an engineer's report are for. Skipping straight to a pier recommendation without measuring first is how homeowners end up paying for more piers than the house needs, or the wrong fix entirely.
The floor-elevation survey
A floor-elevation survey (also called a zone survey or manometer survey) maps the relative height of the floor across the entire house, turning "it feels sloped" into actual numbers: how much drop, and exactly where. This is the baseline measurement that tells a contractor or engineer where the foundation has actually moved, rather than relying on which room feels off when you walk through it.
The independent structural engineer's report
On expansive clay, a structural engineer's report is worth the money. A licensed engineer's inspection, typically $300 to $800, states the cause of the movement and specifies exactly where piers should go, based on measurement rather than a sales walkthrough. That gives a homeowner one written, independent scope to compare contractor bids against, instead of five different companies each proposing a different job with a different pier count. It's harder for a bid to quietly pad the pier count, or skip drainage work, when there's an independent engineer's scope already on the table.
Whether the engineer is truly independent or works for the repair contractor is worth asking directly. Both arrangements exist, and it's useful to know which one you're getting. The vetting questions for this are on choosing a contractor.
Post-tension slabs need a different first step
If a home has a newer post-tensioned slab (steel strands tensioned inside the concrete to resist differential movement), a diagnosis has to start differently. A pro scans the slab with ground-penetrating radar (GPR) to locate the tensioned cables before anyone cores into or drills the concrete. Drilling a post-tension slab blind risks cutting a live, tensioned cable, which is a significant safety and repair problem in its own right. If a home was built with a post-tension foundation, confirming that with whoever inspects it, before any coring or piering, is a non-negotiable first step.
What the diagnosis tells you next
Once the elevation survey and the engineer's report are in hand, the findings point to one of a handful of repair paths: which pier method fits the soil and the structure's weight, how many piers the settlement pattern calls for, and whether drainage or moisture correction needs to happen alongside the piering. Those options are compared on repair methods and piers, and the honest cost ranges that follow from a real pier count are on what foundation repair costs.
Area covered
Alvin, TX (ZIP 77511/77512) and Brazoria County.