Frost Line Depth in New York County, New York

  • New York state rule
  • Checked Oct 2026
  • Sources

State-set value

48in

122 cm · 4 ft

48 in (New York rule)

Set by the state: New York City Building Code 2022 §1809.3.1 (4 ft below the lowest adjacent exposed grade).

Source and how we checked

New York County does not publish its own value; the state rule applies.

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

Climate: 67 nights a year at or below 32 °F (NOAA 1991–2020, New York Cntrl Pk Twr, 0.2 mi).

Checked Oct 2026. Report a correction

How deep is the frost line in New York County?

New York City sets the frost footing depth for New York County at 48 in (122 cm, 4 ft). Footings, piers and other permanent supports must reach at least this depth (IRC R403.1.4.1).

Who sets the frost line depth in New York County?

New York writes this depth into its statewide residential code, so New York County’s building department enforces the state’s number rather than setting its own. See how New York sets frost line depth.

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

Project
House or garage footing in New York County: dig at least 48 in. grade 0 in 122436486072 12 in code minimum frost line 48 in dig 48 in

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

Minimum depths in New York County with a 48 in frost line
ProjectDepthRule
House or garage footing48 inBelow the frost line and at least 12 in deep (IRC R403.1.4)
Deck footing (attached)48 inBelow the frost line and at least 12 in deep (IRC R507.3)
Water service line54 in6 in below the frost line and at least 12 in deep (IRC P2603.5)
Fence post bottom48 inNo 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 New York County?

  1. J
  2. F
  3. M
  4. A
  5. M
  6. J
  7. J
  8. A
  9. S
  10. O
  11. N
  12. D
0°32°100° J F M A M J J A S O N D 32 °F

Average lows are at or below freezing from Jan to Feb. 67 nights a year reach 32 °F or colder; Jan is coldest, with an average low of 27.9 °F.

NOAA 1991–2020 climate normals, New York Cntrl Pk Twr station, 0.2 mi away, elevation 130 ft.

Monthly temperatures as a table
°FJanFebMarAprMayJunJulAugSepOctNovDec
Low27.929.535.845.55564.470.168.962.351.44233.8
High39.542.249.961.871.479.784.983.376.264.55444.3
66201 nightsNew York County 67

New York County has fewer freezing nights than 65 of the 67 other New York places we track. The New York median is 141. Coldest: Franklin County; mildest: Kings County.

What frost line depth do towns near New York County use?

One official code near New York County is verified.

Official frost line depths near New York County
PlaceVerified frost lineDistance
Mount Vernon 42 in 12 mi away

How likely is the soil in New York County to heave?

USDA rates the sampled soil around New York County as 2% none, 98% moderate, 1% high for frost action (main soils: Laguardia, Charlton, Chatfield).

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 New York County?

New York County at a glance

Frost line depth
48 in (New York rule)
Population (2023 est.)
1,597,451
Mean annual temperature
55.8 °F
ZIP codes (70)
10001 · 10002 · 10003 · 10004 · 10005 · 10006 · 10007 · 10009 · 10010 · 10011 · 10012 · 10013 · 10014 · 10016 · 10017 · 10018 · 10019 · 10020 · 10021 · 10022 · 10023 · 10024 · 10025 · 10026 · 10027 · 10028 · 10029 · 10030 · 10031 · 10032 · 10033 · 10034 · 10035 · 10036 · 10037 · 10038 · 10039 · 10040 · 10044 · 10065 · 10069 · 10075 · 10103 · 10110 · 10111 · 10112 · 10115 · 10119 · 10128 · 10152 · 10153 · 10154 · 10162 · 10165 · 10167 · 10168 · 10169 · 10170 · 10171 · 10172 · 10173 · 10174 · 10177 · 10199 · 10271 · 10278 · 10279 · 10280 · 10282 · 10463

Sources

  • Climate: NOAA NCEI U.S. Climate Normals 1991–2020, station USW00094728.
  • Soil: USDA NRCS Soil Survey (SSURGO) frost action ratings.
  • Code rules: International Residential Code R403.1.4, R507.3, P2603.5.

Checked Oct 2026. How we verify · Report a correction