Frost Line Depth in Johnson City, TN: Tennessee Codes Range 5

No official local value

No official frost line depth is published for Johnson City.

No verified code nearby; verified Tennessee codes range 5–13 in.

Source and how we checked

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

Climate: 94 nights a year at or below 32 °F (NOAA 1991–2020, Elizabethton, 7.4 mi).

Checked Oct 2026. Report a correction

Footings Deck Water line Fence post

5–13 inrange of verified Tennessee codes
94nights a year at or below 32 °F
100%of nearby soil rated “none” for frost action (USDA)

Does Johnson City have an official frost line depth?

No adopted frost line depth found for Johnson City in its official documents (checked Oct 2026). No verified code lies near Johnson City; the Tennessee codes we verified range from 5 to 13 in. Ask the building department for Johnson City’s own number before you dig.

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

Call 811 at least a few working days before you dig, so buried lines are marked.
Confirm the frost line depth with the Johnson City building department.
Ask whether your project needs a permit (decks, larger sheds and footings usually do).
Dig below 13 in (the deepest verified state value) unless the building department tells you otherwise.
Book the footing inspection before you pour concrete.

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

Drawn with the deepest Tennessee official value (13 in). Confirm Johnson City’s own depth before you dig.

House or garage footing Deck footing Water service line Fence post

House or garage footing in Johnson City: dig at least 13 in (33 cm). Below the frost line and at least 12 in deep (IRC R403.1.4).

Using the nearby official value of 13 in until Johnson City confirms its own
Project	Depth	Rule
House or garage footing	13 in	Below the frost line and at least 12 in deep (IRC R403.1.4)
Deck footing (attached)	13 in	Below the frost line and at least 12 in deep (IRC R507.3)
Water service line	19 in	6 in below the frost line and at least 12 in deep (IRC P2603.5)
Fence post bottom	13 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 Johnson City?

Average lows are at or below freezing from Dec to Feb. 94 nights a year reach 32 °F or colder; Jan is coldest, with an average low of 25.5 °F.

NOAA 1991–2020 climate normals, Elizabethton station, 7.4 mi away, elevation 1,487 ft.

Monthly temperatures as a table

°F	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Low	25.5	28.1	34.2	41.9	51.8	59.6	63.5	62.3	55.6	44	33.3	28.8
High	46.2	50.4	58.9	69	76.6	82.9	85.5	85	80.1	70	58.5	49.5

Johnson City has more freezing nights than 46 of the 59 other Tennessee places we track. The Tennessee median is 84. Coldest: Greene County; mildest: Memphis.

How likely is the soil in Johnson City to heave?

None 100%

USDA rates the sampled soil around Johnson City as 100% none for frost action (main soils: Dewey, Urban land, Udorthents).

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

Johnson City at a glance

Frost line depth: No official local value
County: Washington County
Population (2023 est.): 73,337
Mean annual temperature: 55.9 °F
ZIP codes (7): 37601 · 37604 · 37614 · 37615 · 37659 · 37686 · 37694