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Concrete Research & Data

Original datasets SlabCalc builds and maintains from primary government and scientific sources — what concrete costs, how hard the climate is on it, and what the ground underneath does to it. Free to cite, reference, and reuse.

The SlabCalc Concrete Cost Index

Professional installed concrete costs across 26 US metros, built from public bid-tabulation records rather than contractor-submitted estimates.

New York is the most expensive bid-data metro at $13.68/sq ft on the low end, 4.1× the cheapest.

Last updated: October 20, 2026

The SlabCalc Freeze-Thaw Index

Mean annual air freeze-thaw cycle counts for 180 US cities, derived from NOAA GHCN-Daily station records, with recommended concrete air content by city.

Carson City, NV leads at 174.1 cycles a year; 132 of 180 cities need air-entrained concrete.

Last updated: October 12, 2026

The SlabCalc Soil Risk Index

Area-weighted expansive soil risk scores for 180 US cities, built from USDA NRCS SSURGO soil survey data, with slab design guidance by risk band.

New Orleans, LA scores highest at 100/100; 18 of 180 cities fall in the high or very high bands.

Last updated: October 15, 2026

What the Indices Show Together

Cheapest concrete, uneven ground

The lowest installed costs in the Concrete Cost Index (from $3.33/sq ft on the low end) belong to Atlanta, Detroit, St. Louis, Charlotte, San Antonio. Their expansive-soil risk in the Soil Risk Index ranges widely:

  • San Antonio, TX: soil risk 77/100
  • St. Louis, MO: soil risk 38/100
  • Atlanta, GA: soil risk 35/100
  • Charlotte, NC: soil risk 26/100
  • Detroit, MI: soil risk 10/100
Scatter chart of 26 metros: low-end installed sidewalk cost vs. soil risk score. The highest-risk metros (San Antonio 77, Dallas 76, Houston and Austin 62) span $4.91 to $8.86 per sq ft; Atlanta is cheapest at $3.33, New York costliest at $13.68 with a score of 10
Low-end installed sidewalk cost vs. soil risk score, 26 bid-data metros. Snapshot, October 2026.

New York, the most expensive metro at $13.68/sq ft, scores 10/100 on soil risk. Price per square foot says little about what a slab that lasts will cost once soil preparation and slab design are included.

Double exposure: freeze-thaw and expansive soil

These cities fall in the high bands of both the Freeze-Thaw Index and the Soil Risk Index, so exterior slabs face both surface scaling and ground movement:

  • Durham, NC: 51.3 freeze-thaw cycles/yr, soil risk 84/100
  • Overland Park, KS: 77.5 freeze-thaw cycles/yr, soil risk 71/100
  • Topeka, KS: 92.5 freeze-thaw cycles/yr, soil risk 69/100
  • Lincoln, NE: 110.1 freeze-thaw cycles/yr, soil risk 67/100

Citing & Coverage

Each index page carries a ready-to-use citation and DOI. For articles that draw on this research, see Press & Mentions. Questions about the data: contact@slabcalc.co.