Two soils, one city
| Compared | Eastern Arlington | Western Arlington |
|---|---|---|
| What the Handbook of Texas says | Fertile Blackland Prairie soil | Sandy loam, once prized for fruit and vegetables |
| What’s beneath | Houston black clay from Eagle Ford shale, called “black waxy” land | Sandier ground of the East Cross Timbers |
| How it treats a slab | Large swings between wet and dry seasons | Less swelling, though clay layers occur |
The Handbook’s summary of the split, Blackland Prairie (east), sandy loam (west), comes from the farmers who settled the area. The city’s own staff say the same thing in modern terms: a City of Arlington presentation on its tree manual says the soil changes dramatically from east to west along the ecoregion boundary.
The USDA’s 1981 Tarrant County survey took reference profiles for two soils inside Arlington, a few miles apart. One is Heiden clay, a clay formed in marine clay and weathered shale, south of I-20 on Farm Road 157. The other is Gasil fine sandy loam, a loamy soil over sandstone, south of I-20 on US 287. Two very different soils under one city is the reason an Arlington inspection has to look at the lot rather than the neighborhood’s reputation.
The city treats its clay seriously in public works. Arlington’s paving specification, as cited in a 2022 regional presentation, calls for lime treatment to bring the plasticity index of street subgrade down to 15% or less before cement treatment. A house slab, once poured, gets no such treatment.
Older houses than the neighbors
Arlington grew earlier than Mansfield or Keller. The Census Bureau puts the median home’s construction year at 1986, with 33% of its 153,137 housing units built before 1980 and just 23% in 2000 or later. Single-family detached houses make up 60% of the housing.
Older housing changes what an inspection finds:
- Slabs that have been through decades of droughts, sometimes with an earlier repair whose paperwork is long gone.
- Raised-floor houses among the oldest homes, where shims, sills and crawl space moisture matter more than piers. See pier and beam repair.
- Original plumbing under the slab, which is worth testing before any lift.
If the house had an earlier repair, ask the seller or the city for the permit record. Repairs done before November 2011 may not have needed one.
Call to schedule an inspection
Arlington’s permit rules and its advice
| Rule | City of Arlington |
|---|---|
| Permit for structural foundation repair | yes (since November 1, 2011) |
| Permit fee | $150.00, plus a non-refundable plan review fee at submittal |
| Who can pull permits | A contractor registered as a business |
| Work found without a permit | a stop work order; some work may have to be uncovered and redone |
Arlington’s permit FAQ adds two lines every homeowner should read. Registration, it says, doesn’t necessarily mean a contractor is reputable, so check references. And homeowners may choose to pay a contractor based upon approval of city inspections. Tie your payment schedule to passed inspections, and get it in writing.
The city’s pages don’t say whether a repair permit needs an engineer’s letter. The permit guide compares Arlington with Fort Worth, Mansfield and Keller.
What repairs cost
No cost guide publishes an Arlington figure. Angi’s Dallas average is $5,223, and Olshan, a contractor, reports $8,379 across its Dallas–Fort Worth jobs. The cost page explains what moves a quote up or down, and the inspection page explains what you should get from the visit that produces it.