Frost Line Depth in Fort Smith, AR: Rogers Requires 18 in

No official local value

No official frost line depth is published for Fort Smith.

Nearby official codes require 18 in (1 verified code).

Source and how we checked

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

Climate: 63 nights a year at or below 32 °F (NOAA 1991–2020, Ft Smith Regional Airport, 1.2 mi).

Checked Oct 2026. Report a correction

Footings Deck Water line Fence post

18 in1 verified code within 68 mi
63nights a year at or below 32 °F
100%of nearby soil rated “none” for frost action (USDA)

Does Fort Smith have an official frost line depth?

No adopted frost line depth found for Fort Smith in its official documents (checked Oct 2026). The nearest official values, from codes we verified, are 18 in. Use the deepest of them until the building department confirms Fort Smith’s own number.

What frost line depth does Fort Smith use for footings under Table R301.2(1)? Is it 18 in, like Rogers?

Call 811 at least a few working days before you dig, so buried lines are marked.
Confirm the frost line depth with the Fort Smith building department.
Ask whether your project needs a permit (decks, larger sheds and footings usually do).
Dig below 18 in (the deepest nearby value) unless the building department tells you otherwise.
Book the footing inspection before you pour concrete.

How deep do footings, decks and water lines need to be in Fort Smith?

Drawn with the deepest nearby official value (18 in). Confirm Fort Smith’s own depth before you dig.

House or garage footing Deck footing Water service line Fence post

House or garage footing in Fort Smith: dig at least 18 in (46 cm). Below the frost line and at least 12 in deep (IRC R403.1.4).

Using the nearby official value of 18 in until Fort Smith confirms its own
Project	Depth	Rule
House or garage footing	18 in	Below the frost line and at least 12 in deep (IRC R403.1.4)
Deck footing (attached)	18 in	Below the frost line and at least 12 in deep (IRC R507.3)
Water service line	24 in	6 in below the frost line and at least 12 in deep (IRC P2603.5)
Fence post bottom	18 in	No 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 Fort Smith?

Average lows are at or below freezing from Jan. 63 nights a year reach 32 °F or colder; Jan is coldest, with an average low of 29.6 °F.

NOAA 1991–2020 climate normals, Ft Smith Regional Airport station, 1.2 mi away, elevation 449 ft.

Monthly temperatures as a table

°F	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Low	29.6	33.4	41.5	49.8	59.5	68.3	72.1	70.9	63.1	51	40	32.3
High	51.3	56.6	65.6	74.5	81.4	89.4	94.1	93.7	86.5	75.9	63.4	53.3

Fort Smith has fewer freezing nights than 16 of the 25 other Arkansas places we track. The Arkansas median is 66. Coldest: Benton County; mildest: Miller County.

What frost line depth do towns near Fort Smith use?

One official code near Fort Smith is verified.

Official frost line depths near Fort Smith
Place	Verified frost line	Distance
Rogers	18 in	68 mi away

How likely is the soil in Fort Smith to heave?

None 100%

USDA rates the sampled soil around Fort Smith as 100% none for frost action (main soils: Wrightsville, Leadvale, Enders).

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

Fort Smith at a glance

Frost line depth: No official local value
County: Sebastian County
Population (2023 est.): 89,770
Mean annual temperature: 62.4 °F
ZIP codes (6): 72901 · 72903 · 72904 · 72908 · 72916 · 72923