Frost Line Depth in Dunwoody, Georgia
- Dunwoody’s adopted code
- Checked Oct 2026
- Sources
Verified
12in
30 cm · 1 ft
Set in the building code Dunwoody has adopted.
Source and how we checked
Document: library.municode.com
Climate: 49 nights a year at or below 32 °F (NOAA 1991–2020, Atlanta Peachtree Airport, 4.6 mi).
Checked Oct 2026. Report a correction
How deep is the frost line in Dunwoody?
Dunwoody's building authority sets the frost line depth at 12 in (30 cm). Footings, piers and other permanent supports must reach at least this depth (IRC R403.1.4.1).
Who sets the frost line depth in Dunwoody?
Georgia leaves the frost line depth to each city or county, and Dunwoody fills it in when it adopts the residential code. The value above comes from Dunwoody’s own document on library.municode.com. See how Georgia sets frost line depth.
How deep do footings, decks and water lines need to be in Dunwoody?
House or garage footing in Dunwoody: dig at least 12 in (30 cm). Below the frost line and at least 12 in deep (IRC R403.1.4).
| 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 | 18 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 Dunwoody?
- J
- F
- M
- A
- M
- J
- J
- A
- S
- O
- N
- D
Dunwoody never averages a low below freezing. 49 nights a year reach 32 °F or colder; Jan is coldest, with an average low of 32.7 °F.
NOAA 1991–2020 climate normals, Atlanta Peachtree Airport station, 4.6 mi away, elevation 1,002 ft.
Monthly temperatures as a table
| °F | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Low | 32.7 | 35.9 | 42.2 | 49.2 | 58.5 | 66.3 | 69.9 | 69.1 | 62.8 | 50.9 | 40.6 | 35.5 |
| High | 51.9 | 56.4 | 64.4 | 72.7 | 80.3 | 86.2 | 89.4 | 88.2 | 82.9 | 72.8 | 62.5 | 54.4 |
Dunwoody has fewer freezing nights than 38 of the 74 other Georgia places we track. The Georgia median is 51. Coldest: Habersham County; mildest: Glynn County.
What frost line depth do towns near Dunwoody use?
3 official codes near Dunwoody are verified; each links to its document.
| Place | Verified frost line | Distance |
|---|---|---|
| Brookhaven | 12 in | 6 mi away |
| Stonecrest | 12 in | 20 mi away |
| Fayette County | 5 in | 38 mi away |
How likely is the soil in Dunwoody to heave?
USDA rates the sampled soil around Dunwoody as 100% none for frost action (main soils: Madison, Rion, Appling).
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 Dunwoody?
Dunwoody at a glance
- Frost line depth
- 12 in
- County
- DeKalb County
- Population (2023 est.)
- 51,713
- Mean annual temperature
- 61.5 °F
- ZIP codes (6)
- 30319 · 30338 · 30341 · 30346 · 30350 · 30360