Frost Line Depth in Dorchester County, South Carolina
- South Carolina range from verified codes
- Checked Oct 2026
No official local value
No official frost line depth is published for Dorchester County.
No verified code nearby; verified South Carolina codes range 0–12 in.
Source and how we checked
We searched this place’s own code and website and found no published frost line depth.
Climate: 45 nights a year at or below 32 °F (NOAA 1991–2020, Summerville 4W, 10.5 mi).
Checked Oct 2026. Report a correction
Does Dorchester County have an official frost line depth?
No adopted frost line depth found for Dorchester County in its official documents (checked Oct 2026). No verified code lies near Dorchester County; the South Carolina codes we verified range from 0 to 12 in. Ask the building department for Dorchester County’s own number before you dig.
What frost line depth does Dorchester County use for footings under Table R301.2(1)?
How deep do footings, decks and water lines need to be in Dorchester County?
Drawn with the deepest South Carolina official value (12 in). Confirm Dorchester County’s own depth before you dig.
House or garage footing in Dorchester County: 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 Dorchester County?
- J
- F
- M
- A
- M
- J
- J
- A
- S
- O
- N
- D
Dorchester County never averages a low below freezing. 45 nights a year reach 32 °F or colder; Jan is coldest, with an average low of 34.5 °F.
NOAA 1991–2020 climate normals, Summerville 4w station, 10.5 mi away, elevation 65 ft.
Monthly temperatures as a table
| °F | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Low | 34.5 | 37 | 42.2 | 49.5 | 59.1 | 67.2 | 70.9 | 70.4 | 64.8 | 53 | 42.2 | 37.4 |
| High | 58.2 | 61.9 | 68.5 | 75.6 | 82.3 | 87.2 | 90.1 | 89.7 | 84.7 | 76.6 | 67.7 | 61.3 |
Dorchester County has fewer freezing nights than 9 of the 13 other South Carolina places we track. The South Carolina median is 53. Coldest: Laurens County; mildest: Beaufort County.
How likely is the soil in Dorchester County to heave?
USDA rates the sampled soil around Dorchester County as 100% none, 0% low for frost action (main soils: Jedburg, Osier, Ogeechee).
USDA NRCS soil survey, 9 sample points within 2 mi. Higher frost action means more risk of heave; see frost heave.
Dorchester County at a glance
- Frost line depth
- No official local value
- Population (2023 est.)
- 169,833
- Mean annual temperature
- 63.8 °F
- ZIP codes (15)
- 29018 · 29414 · 29418 · 29420 · 29426 · 29432 · 29437 · 29448 · 29456 · 29470 · 29471 · 29472 · 29477 · 29483 · 29485