Frost Line Depth in Pinal County, AZ: Casa Grande Requires 0 in

No official local value

No official frost line depth is published for Pinal County.

Nearby official codes require 0 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: 10 nights a year at or below 32 °F (NOAA 1991–2020, Florence, 8.2 mi).

Checked Oct 2026. Report a correction

Footings Deck Water line Fence post

0 in1 verified code within 23 mi
10nights a year at or below 32 °F
100%of nearby soil rated “none” for frost action (USDA)

Does Pinal County have an official frost line depth?

No adopted frost line depth found for Pinal County in its official documents (checked Oct 2026). The nearest official values, from codes we verified, are 0 in. Use the deepest of them until the building department confirms Pinal County’s own number.

What frost line depth does Pinal County use for footings under Table R301.2(1)? Is it 0 in, like Casa Grande?

Call 811 at least a few working days before you dig, so buried lines are marked.
Confirm the frost line depth with the Pinal County building department.
Ask whether your project needs a permit (decks, larger sheds and footings usually do).
Dig below 0 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 Pinal County?

Drawn with the deepest nearby official value (0 in). Confirm Pinal County’s own depth before you dig.

House or garage footing Deck footing Water service line Fence post

House or garage footing in Pinal County: dig at least 12 in (30 cm). Below the frost line and at least 12 in deep (IRC R403.1.4).

Using the nearby official value of 0 in until Pinal County confirms its own
Project	Depth	Rule
House or garage footing	12 in	Below the frost line and at least 12 in deep (IRC R403.1.4)
Deck footing (attached)	12 in	Below the frost line and at least 12 in deep (IRC R507.3)
Water service line	12 in	6 in below the frost line and at least 12 in deep (IRC P2603.5)
Fence post bottom	12 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 Pinal County?

Pinal County never averages a low below freezing. 10 nights a year reach 32 °F or colder; Dec is coldest, with an average low of 41.3 °F.

NOAA 1991–2020 climate normals, Florence station, 8.2 mi away, elevation 1,400 ft.

Monthly temperatures as a table

°F	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Low	42.2	43.9	49.1	53.3	60.9	70.4	78.3	77.7	71.8	59.6	48.2	41.3
High	67.7	70.8	78.5	85.9	94.1	103	104.9	103.2	99.1	89	77.2	66.8

Pinal County has fewer freezing nights than 20 of the 35 other Arizona places we track. The Arizona median is 12. Coldest: Flagstaff; mildest: Yuma.

What frost line depth do towns near Pinal County use?

One official code near Pinal County is verified.

Official frost line depths near Pinal County
Place	Verified frost line	Distance
Casa Grande	0 in	23 mi away

How likely is the soil in Pinal County to heave?

None 100%

USDA rates the sampled soil around Pinal County as 100% none for frost action (main soils: Mohall, Contine, Dateland).

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

Pinal County at a glance

Frost line depth: No official local value
Population (2023 est.): 484,239
Mean annual temperature: 72.4 °F
ZIP codes (35): 85118 · 85119 · 85120 · 85121 · 85122 · 85123 · 85128 · 85131 · 85132 · 85137 · 85138 · 85139 · 85140 · 85141 · 85142 · 85143 · 85145 · 85147 · 85172 · 85173 · 85191 · 85192 · 85193 · 85194 · 85212 · 85248 · 85339 · 85539 · 85618 · 85623 · 85631 · 85634 · 85653 · 85658 · 85739