Frost Line Depth in Maricopa, Arizona

  • Maricopa’s adopted code
  • Checked Oct 2026
  • Sources

Verified

0in

No frost depth required

Set in the building code Maricopa has adopted.

Footings still go at least 12 in (30 cm) below undisturbed ground (IRC R403.1.4).

Source and how we checked

Document: maricopa.gov

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

Checked Oct 2026. Report a correction

How deep is the frost line in Maricopa?

Maricopa's building authority sets the frost line depth at 0 in (0 cm). Footings, piers and other permanent supports still go at least 12 in below undisturbed ground (IRC R403.1.4).

Who sets the frost line depth in Maricopa?

Arizona has no statewide residential code, so Maricopa adopts its own and fills in the frost line depth. The value above comes from Maricopa’s own document on maricopa.gov. See how Arizona sets frost line depth.

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

Project
House or garage footing in Maricopa: dig at least 12 in. grade 0 in 122436486072 12 in code minimum frost line 0 in dig 12 in

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

Minimum depths in Maricopa with a 0 in frost line
ProjectDepthRule
House or garage footing12 inBelow the frost line and at least 12 in deep (IRC R403.1.4)
Deck footing (attached)12 inBelow the frost line and at least 12 in deep (IRC R507.3)
Water service line12 in6 in below the frost line and at least 12 in deep (IRC P2603.5)
Fence post bottom12 inNo 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 Maricopa?

  1. J
  2. F
  3. M
  4. A
  5. M
  6. J
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  12. D
0°32°110° J F M A M J J A S O N D 32 °F

Maricopa never averages a low below freezing. 32 nights a year reach 32 °F or colder; Dec is coldest, with an average low of 35.3 °F.

NOAA 1991–2020 climate normals, Maricopa 4 N station, 5.3 mi away, elevation 1,160 ft.

Monthly temperatures as a table
°FJanFebMarAprMayJunJulAugSepOctNovDec
Low36.739.844.550.859.468.677.877.269.154.642.735.3
High6972.980.288.297.4107.1108.9107.3102.391.278.167.5
0202 nightsMaricopa 32

Maricopa has more freezing nights than 22 of the 35 other Arizona places we track. The Arizona median is 12. Coldest: Flagstaff; mildest: Yuma.

What frost line depth do towns near Maricopa use?

One official code near Maricopa is verified.

Official frost line depths near Maricopa
PlaceVerified frost lineDistance
Casa Grande 0 in 17 mi away

How likely is the soil in Maricopa to heave?

USDA rates the sampled soil around Maricopa as 100% none for frost action (main soils: Casa Grande, Trix, Glenbar).

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 Maricopa?

Maricopa at a glance

Frost line depth
0 in
County
Pinal County
Population (2023 est.)
71,022
Mean annual temperature
71.9 °F
ZIP codes (3)
85138 · 85139 · 85172