Why Do Foundations Crack in Tarrant County?

What Does the Soil Survey Say About Tarrant County?

Soil Data Access, the USDA service that publishes the SSURGO soil survey, rates every soil by linear extensibility: the percent a clod lengthens between oven-dry and wet. In Tarrant County 32% of rated acres fall in the low class, 13.8% in moderate, 41.4% in high and 12.7% in very high. A stable lot can sit a few blocks from an active one, and the survey cannot say which kind yours is.

Picture a slab sitting on that clay. Wet one corner with a downspout and that corner rises. Let a big oak drink from the other side and that side sinks. The slab is stiff, so it bends between the two, and the bend is what splits drywall and brick. Nothing has to be wrong with the concrete for this to happen.

The firm is based in Arlington, in Tarrant County, and Heath Salmon, PE, spent ten years in his family's foundation repair business before he held a license. The county numbers on this page are the context for an inspection. The inspection itself is a visit to one house, and the report says what the engineer saw there.

Which Tarrant County Soils Carry the High Ratings?

Of the 300 soil components the survey maps in Tarrant County, the ones that add the most high or very high acreage are Sanger (54,050 acres), Crosstell (31,042) and Frio (20,152). The table lists the top five. Acres here are map-unit acres multiplied by each component's share of its map unit, so a soil that makes up half of a map unit counts for half of its acres.

27.5% of Tarrant County is not rated at all, the largest unrated share among the seven counties after Dallas. Most of that is urban land, water and pits, where the survey has no layer data. The percentages above use only the rated acres, and a house on unrated ground tells you nothing from this table.

How Dry Has Tarrant County Been Since 2021?

Every week the U.S. Drought Monitor says how much of each county is in each drought class. Over the 262 weeks from 2021-10-12 to 2026-10-13, part of Tarrant County sat in D2 (severe drought) or worse for 74 of them. For 57 weeks that was half the county or more, and for 22 weeks half of it was in D3 (extreme) or worse.

The weeks are not spread evenly. Tarrant County had 43 such weeks in 2022 and 21 in 2023, then 2 in 2024 and 0 in 2025. The 2026 count is 8 weeks so far. Soil that dries for most of a year and then takes a wet spring is exactly the cycle that moves a slab, and the report cannot say which year did the moving. It can say what the house looks like now.

What Does an Inspection Do With This Information?

Heath Salmon, PE, does not start from the map. The visit starts at the curb, with where water runs off the lot and where each gutter lets go. Earlier repairs come next, then the floors, the doors and the brick. The sealed report lists what was found that day.

The firm sells no repair work, so nothing in the report depends on finding one to fix.

See the foundation inspection service page or use the request form.

How Were These Numbers Made?

Method: for each soil component in the Tarrant County SSURGO survey, the script averages linear extensibility over the top 100 centimeters, weighted by horizon depth. The average puts the component in an NRCS class: low under 3 percent, moderate 3 to under 6, high 6 to under 9, very high 9 or more. Acres are the map unit's acres times the component's percent of the unit, and components with no reading are left out of the percentages. The Drought Monitor figures are weekly county statistics. Both raw pulls are committed with the scripts, and a gate re-runs them before each build. A soil survey describes a county, never a single lot.

Where Does the Firm Work in Tarrant County?

• Foundation inspection in Arlington, TX
• Foundation inspection in Fort Worth, TX
• Foundation inspection in Mansfield, TX
• Foundation inspection in Grapevine, TX
• Foundation inspection service
• Other counties: Dallas, Johnson, Ellis, Parker