Sarpy County, NE Frost Line Depth: 42 in

Verified

42in

107 cm · 3 ft 6 in

Set in the building code Sarpy County has adopted.

Source and how we checked

Document: sarpy.gov

Climate: 136 nights a year at or below 32 °F (NOAA 1991–2020, Gretna 4Ne, 5.3 mi).

Checked Oct 2026. Report a correction

Footings Deck Water line Fence post

136nights a year at or below 32 °F
100%of nearby soil rated “high” for frost action (USDA)

How deep is the frost line in Sarpy County?

Sarpy County's building authority sets the frost line depth at 42 in (107 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 Sarpy County?

Nebraska leaves the frost line depth to each city or county, and Sarpy County fills it in when it adopts the residential code. The value above comes from Sarpy County’s own document on sarpy.gov. See how Nebraska sets frost line depth.

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

House or garage footing Deck footing Water service line Fence post

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

Minimum depths in Sarpy County with a 42 in frost line
Project	Depth	Rule
House or garage footing	42 in	Below the frost line and at least 12 in deep (IRC R403.1.4)
Deck footing (attached)	42 in	Below the frost line and at least 12 in deep (IRC R507.3)
Water service line	48 in	6 in below the frost line and at least 12 in deep (IRC P2603.5)
Fence post bottom	42 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 Sarpy County?

Average lows are at or below freezing from Nov to Mar. 136 nights a year reach 32 °F or colder; Jan is coldest, with an average low of 14 °F.

NOAA 1991–2020 climate normals, Gretna 4ne station, 5.3 mi away, elevation 1,240 ft.

Monthly temperatures as a table

°F	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Low	14	17.5	28.3	38.5	50.7	61.8	65.8	63.5	54.3	41.5	28.7	18.7
High	32.4	37.4	50	62	72.4	82.7	85.9	83.9	77.3	64.4	49.2	36.5

Sarpy County has fewer freezing nights than 5 of the 7 other Nebraska places we track. The Nebraska median is 143. Coldest: Buffalo County; mildest: Douglas County.

How likely is the soil in Sarpy County to heave?

High 100%

USDA rates the sampled soil around Sarpy County as 0% moderate, 100% high for frost action (main soils: Contrary, Marshall, Ida).

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 Sarpy County?

Call 811 at least a few working days before you dig, so buried lines are marked.
Confirm the frost line depth with the Sarpy County building department.
Ask whether your project needs a permit (decks, larger sheds and footings usually do).
Dig below 42 in unless the building department tells you otherwise.
Book the footing inspection before you pour concrete.

Sarpy County at a glance

Frost line depth: 42 in
Population (2023 est.): 199,886
Mean annual temperature: 50.7 °F
ZIP codes (14): 68005 · 68028 · 68046 · 68056 · 68059 · 68069 · 68113 · 68123 · 68128 · 68133 · 68136 · 68138 · 68147 · 68157