Frost Line Depth in Warren County, Iowa

  • 3 verified codes nearby
  • Checked Oct 2026

No official local value

No official frost line depth is published for Warren County.

Nearby official codes require 42 in (3 verified codes).

Source and how we checked

We searched this place’s own code and website and found no published frost line depth.

Climate: 143 nights a year at or below 32 °F (NOAA 1991–2020, Indianola 2W, 4.7 mi).

Checked Oct 2026. Report a correction

Does Warren County have an official frost line depth?

No adopted frost line depth found for Warren County in its official documents (checked Oct 2026). The nearest official values, from codes we verified, are 42 in. Use the deepest of them until the building department confirms Warren County’s own number.

What frost line depth does Warren County use for footings under Table R301.2(1)? Is it 42 in, like West Des Moines?

How deep do footings, decks and water lines need to be in Warren County?

Drawn with the deepest nearby official value (42 in). Confirm Warren County’s own depth before you dig.

Project
House or garage footing in Warren County: dig at least 42 in. grade 0 in 122436486072 12 in code minimum nearby codes 42 in, confirm locally dig 42 in

House or garage footing in Warren County: dig at least 42 in (107 cm). Below the frost line and at least 12 in deep (IRC R403.1.4).

Using the nearby official value of 42 in until Warren County confirms its own
ProjectDepthRule
House or garage footing42 inBelow the frost line and at least 12 in deep (IRC R403.1.4)
Deck footing (attached)42 inBelow the frost line and at least 12 in deep (IRC R507.3)
Water service line48 in6 in below the frost line and at least 12 in deep (IRC P2603.5)
Fence post bottom42 inNo code rule; common practice is below the frost line

Work out posts, concrete and footing sizes with the fence post depth calculator or the deck footing calculator.

How cold does it get in Warren County?

  1. J
  2. F
  3. M
  4. A
  5. M
  6. J
  7. J
  8. A
  9. S
  10. O
  11. N
  12. D
0°32°100° J F M A M J J A S O N D 32 °F

Average lows are at or below freezing from Nov to Mar. 143 nights a year reach 32 °F or colder; Jan is coldest, with an average low of 11.6 °F.

NOAA 1991–2020 climate normals, Indianola 2w station, 4.7 mi away, elevation 924 ft.

Monthly temperatures as a table
°FJanFebMarAprMayJunJulAugSepOctNovDec
Low11.615.227.137.949.9606461.652.440.127.917.4
High31.736.349.562.171.981.485.58477.664.849.636.9
118161 nightsWarren County 143

Warren County has fewer freezing nights than 16 of the 28 other Iowa places we track. The Iowa median is 144. Coldest: Cerro Gordo County; mildest: Davenport.

What frost line depth do towns near Warren County use?

3 official codes near Warren County are verified; each links to its document.

Official frost line depths near Warren County
PlaceVerified frost lineDistance
West Des Moines 42 in 19 mi away
Ankeny 42 in 28 mi away
Dallas County 42 in 35 mi away

How likely is the soil in Warren County to heave?

USDA rates the sampled soil around Warren County as 43% moderate, 57% high for frost action (main soils: Sharpsburg, Colo, Givin).

USDA NRCS soil survey, 9 sample points within 2 mi. Higher frost action means more risk of heave; see frost heave.

Warren County at a glance

Frost line depth
No official local value
Population (2023 est.)
55,205
Mean annual temperature
49.9 °F
ZIP codes (21)
50001 · 50047 · 50061 · 50118 · 50125 · 50139 · 50145 · 50151 · 50160 · 50166 · 50210 · 50211 · 50225 · 50229 · 50240 · 50241 · 50252 · 50257 · 50265 · 50320 · 50321

Sources

  • Climate: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00134063.
  • Soil: USDA NRCS Soil Survey (SSURGO) frost action ratings.
  • Code rules: International Residential Code R403.1.4, R507.3, P2603.5.

Checked Oct 2026. How we verify · Report a correction