Pocatello, ID Frost Line Depth: 36 in

Verified

36in

91 cm · 3 ft

Set in the building code Pocatello has adopted.

Source and how we checked

Document: pocatello.gov

Climate: 132 nights a year at or below 32 °F (NOAA 1991–2020, Pocatello City, 0.9 mi).

Checked Oct 2026. Report a correction

Footings Deck Water line Fence post

0 of 1nearby verified codes use the same depth
132nights a year at or below 32 °F
53%of nearby soil rated “moderate” for frost action (USDA)

How deep is the frost line in Pocatello?

Pocatello's building authority sets the frost line depth at 36 in (91 cm). Footings, piers and other permanent supports must reach at least this depth (IRC R403.1.4.1).

Who sets the frost line depth in Pocatello?

Idaho leaves the frost line depth to each city or county, and Pocatello fills it in when it adopts the residential code. The value above comes from Pocatello’s own document on pocatello.gov. Bannock County uses the same 36 in, so the depth does not change at the city limits. See how Idaho sets frost line depth.

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

House or garage footing Deck footing Water service line Fence post

House or garage footing in Pocatello: dig at least 36 in (91 cm). Below the frost line and at least 12 in deep (IRC R403.1.4).

Minimum depths in Pocatello with a 36 in frost line
Project	Depth	Rule
House or garage footing	36 in	Below the frost line and at least 12 in deep (IRC R403.1.4)
Deck footing (attached)	36 in	Below the frost line and at least 12 in deep (IRC R507.3)
Water service line	42 in	6 in below the frost line and at least 12 in deep (IRC P2603.5)
Fence post bottom	36 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 Pocatello?

Average lows are at or below freezing from Nov to Mar. 132 nights a year reach 32 °F or colder; Jan is coldest, with an average low of 20.9 °F.

NOAA 1991–2020 climate normals, Pocatello City station, 0.9 mi away, elevation 4,460 ft.

Monthly temperatures as a table

°F	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Low	20.9	22.1	30.9	36.7	44.3	51.9	59	56.9	48.7	38.4	28.5	21
High	36.3	40.6	52.1	60.8	70.5	80	90.7	88.6	78.4	63.2	47.3	36.1

Pocatello has fewer freezing nights than 6 of the 13 other Idaho places we track. The Idaho median is 132. Coldest: Madison County; mildest: Canyon County.

What frost line depth do towns near Pocatello use?

One official code near Pocatello is verified.

Official frost line depths near Pocatello
Place	Verified frost line	Distance
Bingham County	30 in	24 mi away

How likely is the soil in Pocatello to heave?

Low 32%Moderate 53%High 16%

USDA rates the sampled soil around Pocatello as 32% low, 53% moderate, 16% high for frost action (main soils: Pocatello, Broncho, Broxon).

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

How do you confirm the frost line before you dig in Pocatello?

Call 811 at least a few working days before you dig, so buried lines are marked.
Confirm the frost line depth with the Pocatello building department.
Ask whether your project needs a permit (decks, larger sheds and footings usually do).
Dig below 36 in unless the building department tells you otherwise.
Book the footing inspection before you pour concrete.

Pocatello at a glance

Frost line depth: 36 in
County: Bannock County
Population (2023 est.): 58,064
Mean annual temperature: 50.1 °F
ZIP codes (4): 83201 · 83202 · 83204 · 83209