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?
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).
| 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 New York County?
- J
- F
- M
- A
- M
- J
- J
- A
- S
- O
- N
- D
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
| °F | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Low | 27.9 | 29.5 | 35.8 | 45.5 | 55 | 64.4 | 70.1 | 68.9 | 62.3 | 51.4 | 42 | 33.8 |
| High | 39.5 | 42.2 | 49.9 | 61.8 | 71.4 | 79.7 | 84.9 | 83.3 | 76.2 | 64.5 | 54 | 44.3 |
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.
| Place | Verified frost line | Distance |
|---|---|---|
| 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