Expansive Soil in Dallas County, TX
Does Dallas County, TX have expansive soil? Yes: the dominant shrink-swell rating for Dallas County, TX is Very High, with 45% of the county's mapped soil acres in the Very High class.
Soil class breakdown for Dallas County
What a Very High rating means for a slab foundation
Soils in this class are among the most expansive that the USDA maps. Large moisture-driven volume changes put sustained stress on slab foundations, and differential movement is a routine cause of structural cracking. Builders and repair contractors in these counties typically plan for it with deep piers, moisture barriers, and strict drainage control.
This is a county-level rating built from USDA soil survey data, not a parcel-level geotechnical assessment. Soils change from lot to lot; a geotechnical engineer or foundation professional can assess the ground under your specific property.
Foundation repair in Dallas County
If you are seeing cracks, sticking doors, or sloping floors, compare local pros and typical repair pricing for covered cities in Dallas County:
Contractors serving Dallas
Methodology and sources
This rating is computed from USDA NRCS SSURGO soil survey data
:
for each soil component we take the maximum linear extensibility percent
(lep_r) among horizons starting within 0 to 100 cm of the surface, apply the
NRCS National Soil Survey Handbook Part 618 class limits (Low under 3 percent, Moderate 3
to under 6, High 6 to under 9, Very High 9 and above), assign each map unit the class
holding the plurality of component percent, and sum map unit acres per class across the
county, excluding unmapped and water areas.
- Data source: USDA NRCS SSURGO via Soil Data Access
- Class limits: NRCS National Soil Survey Handbook, Part 618
- Survey coverage: 91% of county map acres
- Computed: 2026-07-05
- Note: max lep_r over horizons with hzdept_r<100cm (major components only), comppct_r plurality per mapunit, county rollup by muaoverlap.areaovacres, class limits NSSH Part 618, shares are fractions of rated acres
FAQ
Does Dallas County, TX have expansive soil?
Yes: the dominant shrink-swell rating for Dallas County, TX is Very High, with 45% of the county's mapped soil acres in the Very High class.
What does a Very High rating mean for a slab foundation?
Soils in this class are among the most expansive that the USDA maps. Large moisture-driven volume changes put sustained stress on slab foundations, and differential movement is a routine cause of structural cracking. Builders and repair contractors in these counties typically plan for it with deep piers, moisture barriers, and strict drainage control.
Is this a parcel-level soil report?
No. This is a county-level rollup of USDA NRCS SSURGO soil survey data for Dallas County, TX. Soils vary lot to lot, so a geotechnical engineer or foundation professional should assess your specific property before you make repair decisions.
How much does foundation repair cost near Dallas County?
Pricing depends on the repair method and how far the movement has progressed, from sealing a single crack to installing piers. SlabLocal publishes city-level foundation repair cost guides with sourced ranges for cities across Texas.