Worcester County, MD Frost Line Depth: 18 in

Verified

18in

46 cm · 1 ft 6 in

Set in the building code Worcester County has adopted.

Source and how we checked

Document: labor.maryland.gov

Climate: 88 nights a year at or below 32 °F (NOAA 1991–2020, Snow Hill 4 N, 3.7 mi).

Checked Oct 2026. Report a correction

Footings Deck Water line Fence post

0 of 1nearby verified codes use the same depth
88nights a year at or below 32 °F
77%of nearby soil rated “high” for frost action (USDA)

How deep is the frost line in Worcester County?

Worcester County's building authority sets the frost line depth at 18 in (46 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 Worcester County?

Maryland leaves the frost line depth to each city or county, and Worcester County fills it in when it adopts the residential code. The value above comes from Worcester County’s own document on labor.maryland.gov. See how Maryland sets frost line depth.

How deep do footings, decks and water lines need to be in Worcester County?

House or garage footing Deck footing Water service line Fence post

House or garage footing in Worcester County: dig at least 18 in (46 cm). Below the frost line and at least 12 in deep (IRC R403.1.4).

Minimum depths in Worcester County with a 18 in frost line
Project	Depth	Rule
House or garage footing	18 in	Below the frost line and at least 12 in deep (IRC R403.1.4)
Deck footing (attached)	18 in	Below the frost line and at least 12 in deep (IRC R507.3)
Water service line	24 in	6 in below the frost line and at least 12 in deep (IRC P2603.5)
Fence post bottom	18 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 Worcester County?

Average lows are at or below freezing from Jan to Feb. 88 nights a year reach 32 °F or colder; Jan is coldest, with an average low of 30.2 °F.

NOAA 1991–2020 climate normals, Snow Hill 4 N station, 3.7 mi away, elevation 30 ft.

Monthly temperatures as a table

°F	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Low	30.2	31.1	37	46.2	55.7	65	69.5	67.1	61.4	49.8	40.4	34.1
High	48.7	51.3	58.3	69.3	77.8	85.4	89.3	87.4	82.2	72.4	61.3	52.4

Worcester County has fewer freezing nights than 5 of the 6 other Maryland places we track. The Maryland median is 98. Coldest: Bowie; mildest: Gaithersburg.

What frost line depth do towns near Worcester County use?

One official code near Worcester County is verified.

Official frost line depths near Worcester County
Place	Verified frost line	Distance
Calvert County	24 in	69 mi away

How likely is the soil in Worcester County to heave?

Low 12%High 77%

USDA rates the sampled soil around Worcester County as 12% low, 11% moderate, 77% high for frost action (main soils: Othello, Matapeake, Hambrook).

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 Worcester County?

Call 811 at least a few working days before you dig, so buried lines are marked.
Confirm the frost line depth with the Worcester County building department.
Ask whether your project needs a permit (decks, larger sheds and footings usually do).
Dig below 18 in unless the building department tells you otherwise.
Book the footing inspection before you pour concrete.

Worcester County at a glance

Frost line depth: 18 in
Population (2023 est.): 54,171
Mean annual temperature: 59.3 °F
ZIP codes (12): 21804 · 21811 · 21813 · 21822 · 21829 · 21841 · 21842 · 21851 · 21862 · 21863 · 21864 · 21872