Lyon County, NV Frost Line Depth: 18 in Below 5,000 ft, 24 in Above

Verified

18in

46 cm · 1 ft 6 in

18 in Below 5,000 ft, 24 in Above

Set in the building code Lyon County has adopted.

Source and how we checked

Document: lyon-county.org

Climate: 136 nights a year at or below 32 °F (NOAA 1991–2020, Yerington, 2.7 mi).

Checked Oct 2026. Report a correction

Footings Deck Water line Fence post

1 of 1nearby verified codes use the same depth
136nights a year at or below 32 °F
41%of nearby soil rated “high” for frost action (USDA)

How deep is the frost line in Lyon County?

Lyon County's building authority sets the frost line depth at 18 in (46 cm) below 5,000 ft elevation and 24 in (61 cm) at or above it. Footings, piers and other permanent supports must reach at least this depth (IRC R403.1.4.1).

Who sets the frost line depth in Lyon County?

Nevada leaves the frost line depth to each city or county, and Lyon County fills it in when it adopts the residential code. The value above comes from Lyon County’s own document on lyon-county.org. See how Nevada sets frost line depth.

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

House or garage footing Deck footing Water service line Fence post

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

Minimum depths in Lyon County with a 18 in frost line
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 Lyon County?

Average lows are at or below freezing from Nov to Mar. 136 nights a year reach 32 °F or colder; Dec is coldest, with an average low of 21.8 °F.

NOAA 1991–2020 climate normals, Yerington station, 2.7 mi away, elevation 4,380 ft.

Monthly temperatures as a table

°F	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Low	22.7	25.7	31.8	36.8	44.6	52	58.6	56.5	48.9	38	27.6	21.8
High	45.8	51.1	59.3	65.4	74.6	85	93.4	91.9	83.5	69.6	55	44.2

Lyon County has fewer freezing nights than 3 of the 6 other Nevada places we track. The Nevada median is 136. Coldest: Douglas County; mildest: Henderson.

What frost line depth do towns near Lyon County use?

One official code near Lyon County is verified.

Official frost line depths near Lyon County
Place	Verified frost line	Distance
Douglas County	18 in	24 mi away

How likely is the soil in Lyon County to heave?

Low 25%Moderate 33%High 41%

USDA rates the sampled soil around Lyon County as 25% low, 33% moderate, 41% high for frost action (main soils: Dithod, Theon, Appian).

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 Lyon County?

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

Lyon County at a glance

Frost line depth: 18 in Below 5,000 ft, 24 in Above
Population (2023 est.): 62,583
Mean annual temperature: 53.5 °F
ZIP codes (9): 89403 · 89406 · 89408 · 89428 · 89429 · 89430 · 89444 · 89447 · 89706