Frost Line Depth in Surprise, AZ: Casa Grande Requires 0 in

No official local value

No official frost line depth is published for Surprise.

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: 12 nights a year at or below 32 °F (NOAA 1991–2020, Wittmann 1Se, 8.4 mi).

Checked Oct 2026. Report a correction

Footings Deck Water line Fence post

0 in1 verified code within 66 mi
12nights a year at or below 32 °F
100%of nearby soil rated “none” for frost action (USDA)

Does Surprise have an official frost line depth?

No adopted frost line depth found for Surprise 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 Surprise’s own number.

What frost line depth does Surprise 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 Surprise 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 Surprise?

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

House or garage footing Deck footing Water service line Fence post

House or garage footing in Surprise: 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 Surprise 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 Surprise?

Surprise never averages a low below freezing. 12 nights a year reach 32 °F or colder; Dec is coldest, with an average low of 39 °F.

NOAA 1991–2020 climate normals, Wittmann 1se station, 8.4 mi away, elevation 1,683 ft.

Monthly temperatures as a table

°F	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Low	39.2	41.4	45.6	50.6	59.9	69.1	76.8	76.9	69.8	57.1	45.8	39
High	65.2	68.2	74.9	82.1	91.8	101.8	104.6	103.3	97.6	86.5	74.1	64.1

Surprise has fewer freezing nights than 16 of the 35 other Arizona places we track. The Arizona median is 12. Coldest: Flagstaff; mildest: Yuma.

What frost line depth do towns near Surprise use?

One official code near Surprise is verified.

Official frost line depths near Surprise
Place	Verified frost line	Distance
Casa Grande	0 in	66 mi away

How likely is the soil in Surprise to heave?

None 100%

USDA rates the sampled soil around Surprise as 100% none for frost action (main soils: Mohall, Gilman, Tremant).

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

Surprise at a glance

Frost line depth: No official local value
County: Maricopa County
Population (2023 est.): 158,285
Mean annual temperature: 70.2 °F
ZIP codes (11): 85342 · 85355 · 85361 · 85374 · 85375 · 85378 · 85379 · 85383 · 85387 · 85388 · 85396