How an Elevation Survey Reveals Foundation Movement

By Chris Curry · Lighthouse Engineering

Trowbridge, J. T. (John Townsend), 1827-1916 — Public domain (Wikimedia Commons)

Almost every honest foundation diagnosis starts the same way: with a measurement, not an opinion. An elevation survey is how we establish, objectively, whether a floor has moved — and by how much.

What an Elevation Survey Measures

Using a water manometer or a Zip Level, we record the relative height of the floor at points throughout the home. Those readings become a contour map of the slab: where it sits high, where it has dropped, and how sharp the transitions are. A tenth of an inch over thirty feet is normal; two inches across a single room is not.

Reading the Map

The pattern matters as much as the numbers. A gradual dish toward the center reads very differently from a sharp drop along one wall. We overlay the elevation map onto the symptoms you are seeing — the cracks, the sticking doors — to separate normal seasonal movement from a structural problem that needs attention.

Why It Comes First

Measuring before recommending is the whole point. It is the foundation of our foundation inspections and, when the structure above is involved, our structural assessments. Without the numbers, any repair plan is a guess.

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