Frost Line Depth in Franklin County, Tennessee
- 3 verified codes nearby
- Checked Oct 2026
No official local value
No official frost line depth is published for Franklin County.
Nearby official codes require 10–12 in (3 verified codes).
Source and how we checked
We searched this place’s own code and website and found no published frost line depth.
Climate: 71 nights a year at or below 32 °F (NOAA 1991–2020, Winchester 5Se, 3.8 mi).
Checked Oct 2026. Report a correction
Does Franklin County have an official frost line depth?
No adopted frost line depth found for Franklin County in its official documents (checked Oct 2026). The nearest official values, from codes we verified, are 10 to 12 in. Use the deepest of them until the building department confirms Franklin County’s own number.
What frost line depth does Franklin County use for footings under Table R301.2(1)? Is it 12 in, like Murfreesboro?
How deep do footings, decks and water lines need to be in Franklin County?
Drawn with the deepest nearby official value (12 in). Confirm Franklin County’s own depth before you dig.
House or garage footing in Franklin 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 Franklin County?
- J
- F
- M
- A
- M
- J
- J
- A
- S
- O
- N
- D
Average lows are at or below freezing from Jan. 71 nights a year reach 32 °F or colder; Jan is coldest, with an average low of 30.2 °F.
NOAA 1991–2020 climate normals, Winchester 5se station, 3.8 mi away, elevation 941 ft.
Monthly temperatures as a table
| °F | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Low | 30.2 | 33.1 | 39.7 | 47.4 | 56.1 | 64.1 | 67.9 | 66.4 | 60 | 48.5 | 38 | 33.1 |
| High | 48.9 | 53.1 | 61.4 | 70.8 | 78.1 | 84.6 | 87.3 | 87.1 | 82 | 72 | 60.5 | 51.8 |
Franklin County has fewer freezing nights than 46 of the 59 other Tennessee places we track. The Tennessee median is 84. Coldest: Greene County; mildest: Memphis.
What frost line depth do towns near Franklin County use?
3 official codes near Franklin County are verified; each links to its document.
| Place | Verified frost line | Distance |
|---|---|---|
| Murfreesboro | 12 in | 52 mi away |
| Maury County | 10 in | 64 mi away |
| Bradley County | 12 in | 70 mi away |
How likely is the soil in Franklin County to heave?
USDA rates the sampled soil around Franklin County as 100% none for frost action (main soils: Cumberland, Etowah, Whitwell).
USDA NRCS soil survey, 9 sample points within 2 mi. Higher frost action means more risk of heave; see frost heave.
Franklin County at a glance
- Frost line depth
- No official local value
- Population (2023 est.)
- 44,654
- Mean annual temperature
- 59.2 °F
- ZIP codes (16)
- 37306 · 37318 · 37324 · 37328 · 37330 · 37335 · 37345 · 37352 · 37356 · 37366 · 37375 · 37376 · 37380 · 37383 · 37388 · 37398