Frost Line Depth in Glynn County, Georgia

  • Georgia range from verified codes
  • Checked Oct 2026

No official local value

No official frost line depth is published for Glynn County.

No verified code nearby; verified Georgia codes range 5–12 in.

Source and how we checked

We searched this place’s own code and website and found no published frost line depth.

Climate: 9 nights a year at or below 32 °F (NOAA 1991–2020, Brunswick, 3.1 mi).

Checked Oct 2026. Report a correction

Does Glynn County have an official frost line depth?

No adopted frost line depth found for Glynn County in its official documents (checked Oct 2026). No verified code lies near Glynn County; the Georgia codes we verified range from 5 to 12 in. Ask the building department for Glynn County’s own number before you dig.

What frost line depth does Glynn County use for footings under Table R301.2(1)?

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

Drawn with the deepest Georgia official value (12 in). Confirm Glynn County’s own depth before you dig.

Project
House or garage footing in Glynn County: dig at least 12 in. grade 0 in 122436486072 12 in code minimum nearby codes 12 in, confirm locally dig 12 in

House or garage footing in Glynn 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 12 in until Glynn County confirms its own
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 line18 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 Glynn County?

  1. J
  2. F
  3. M
  4. A
  5. M
  6. J
  7. J
  8. A
  9. S
  10. O
  11. N
  12. D
0°32°100° J F M A M J J A S O N D 32 °F

Glynn County never averages a low below freezing. 9 nights a year reach 32 °F or colder; Jan is coldest, with an average low of 44 °F.

NOAA 1991–2020 climate normals, Brunswick station, 3.1 mi away, elevation 13 ft.

Monthly temperatures as a table
°FJanFebMarAprMayJunJulAugSepOctNovDec
Low444752.659.267.172.975.375.17263.152.946.9
High6164.370.176.38387.590.388.884.377.569.263.3
993 nightsGlynn County 9

Glynn County has fewer freezing nights than 74 of the 74 other Georgia places we track. The Georgia median is 51. Coldest: Habersham County; mildest: Glynn County.

How likely is the soil in Glynn County to heave?

USDA rates the sampled soil around Glynn County as 100% none for frost action (main soils: Mandarin, Leon, Rutlege).

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

Glynn County at a glance

Frost line depth
No official local value
Population (2023 est.)
86,172
Mean annual temperature
68.5 °F
ZIP codes (9)
31520 · 31522 · 31523 · 31524 · 31525 · 31527 · 31543 · 31561 · 31566

Sources

  • Climate: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00091340.
  • Soil: USDA NRCS Soil Survey (SSURGO) frost action ratings.
  • Code rules: International Residential Code R403.1.4, R507.3, P2603.5.

Checked Oct 2026. How we verify · Report a correction