Fall River, MA Frost Line Depth: 48 in

Verified

48in

122 cm · 4 ft

Set in the building code Fall River has adopted.

Source and how we checked

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

Climate: 123 nights a year at or below 32 °F (NOAA 1991–2020, New Bedford Municipal Airport, 7.8 mi).

Checked Oct 2026. Report a correction

Footings Deck Water line Fence post

123nights a year at or below 32 °F
96%of nearby soil rated “moderate” for frost action (USDA)

How deep is the frost line in Fall River?

Fall River's building authority sets the frost line depth at 48 in (122 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 Fall River?

Massachusetts sets frost line depth in its state code, and Fall River’s own document lists the value above. Bristol County uses the same 48 in, so the depth does not change at the city limits. See how Massachusetts sets frost line depth.

How deep do footings, decks and water lines need to be in Fall River?

House or garage footing Deck footing Water service line Fence post

House or garage footing in Fall River: dig at least 48 in (122 cm). Below the frost line and at least 12 in deep (IRC R403.1.4).

Minimum depths in Fall River with a 48 in frost line
Project	Depth	Rule
House or garage footing	48 in	Below the frost line and at least 12 in deep (IRC R403.1.4)
Deck footing (attached)	48 in	Below the frost line and at least 12 in deep (IRC R507.3)
Water service line	54 in	6 in below the frost line and at least 12 in deep (IRC P2603.5)
Fence post bottom	48 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 Fall River?

Average lows are at or below freezing from Dec to Mar. 123 nights a year reach 32 °F or colder; Jan is coldest, with an average low of 20.7 °F.

NOAA 1991–2020 climate normals, New Bedford Municipal Airport station, 7.8 mi away, elevation 80 ft.

Monthly temperatures as a table

°F	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Low	20.7	21.7	27.9	36.4	46	55	61.6	60	52.4	41.8	33.3	26
High	39.1	40.9	47.3	57.4	67.4	76.3	82.5	81.2	74	63.5	53.5	44.1

Fall River has fewer freezing nights than 25 of the 38 other Massachusetts places we track. The Massachusetts median is 130. Coldest: Berkshire County; mildest: Malden.

How likely is the soil in Fall River to heave?

Moderate 96%

USDA rates the sampled soil around Fall River as 96% moderate, 4% high for frost action (main soils: Paxton, Woodbridge, Charlton).

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 Fall River?

Call 811 at least a few working days before you dig, so buried lines are marked.
Confirm the frost line depth with the Fall River building department.
Ask whether your project needs a permit (decks, larger sheds and footings usually do).
Dig below 48 in unless the building department tells you otherwise.
Book the footing inspection before you pour concrete.

Fall River at a glance

Frost line depth: 48 in
County: Bristol County
Population (2023 est.): 93,840
Mean annual temperature: 50.4 °F
ZIP codes (7): 02717 · 02720 · 02721 · 02723 · 02724 · 02747 · 02790