Frost Line Depth in Westchester County, New York

  • 1 verified code nearby
  • Checked Oct 2026

No official local value

No official frost line depth is published for Westchester County.

Nearby official codes require 42 in (1 verified code).

Source and how we checked

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

Climate: 105 nights a year at or below 32 °F (NOAA 1991–2020, Westchester Co Airport, 6.3 mi).

Checked Oct 2026. Report a correction

Does Westchester County have an official frost line depth?

No adopted frost line depth found for Westchester County in its official documents (checked Oct 2026). The nearest official values, from codes we verified, are 42 in. Use the deepest of them until the building department confirms Westchester County’s own number.

What frost line depth does Westchester County use for footings under Table R301.2(1)? Is it 42 in, like Mount Vernon?

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

Drawn with the deepest nearby official value (42 in). Confirm Westchester County’s own depth before you dig.

Project
House or garage footing in Westchester County: dig at least 42 in. grade 0 in 122436486072 12 in code minimum nearby codes 42 in, confirm locally dig 42 in

House or garage footing in Westchester County: dig at least 42 in (107 cm). Below the frost line and at least 12 in deep (IRC R403.1.4).

Using the nearby official value of 42 in until Westchester County confirms its own
ProjectDepthRule
House or garage footing42 inBelow the frost line and at least 12 in deep (IRC R403.1.4)
Deck footing (attached)42 inBelow the frost line and at least 12 in deep (IRC R507.3)
Water service line48 in6 in below the frost line and at least 12 in deep (IRC P2603.5)
Fence post bottom42 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 Westchester County?

  1. J
  2. F
  3. M
  4. A
  5. M
  6. J
  7. J
  8. A
  9. S
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  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 Dec to Mar. 105 nights a year reach 32 °F or colder; Jan is coldest, with an average low of 22.4 °F.

NOAA 1991–2020 climate normals, Westchester Co Airport station, 6.3 mi away, elevation 379 ft.

Monthly temperatures as a table
°FJanFebMarAprMayJunJulAugSepOctNovDec
Low22.423.730.540.149.859.164.963.656.745.536.228
High37.340.147.659.269.27883.281.274.26352.242.3
66201 nightsWestchester County 105

Westchester County has fewer freezing nights than 57 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 Westchester County use?

One official code near Westchester County is verified.

Official frost line depths near Westchester County
PlaceVerified frost lineDistance
Mount Vernon 42 in 17 mi away

How likely is the soil in Westchester County to heave?

USDA rates the sampled soil around Westchester County as 5% none, 69% moderate, 26% high for frost action (main soils: Charlton, Chatfield, Leicester).

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

Westchester County at a glance

Frost line depth
No official local value
Population (2023 est.)
990,817
Mean annual temperature
52 °F
ZIP codes (78)
10470 · 10501 · 10502 · 10503 · 10504 · 10505 · 10506 · 10507 · 10509 · 10510 · 10511 · 10514 · 10517 · 10518 · 10519 · 10520 · 10522 · 10523 · 10526 · 10527 · 10528 · 10530 · 10532 · 10533 · 10535 · 10536 · 10537 · 10538 · 10540 · 10541 · 10543 · 10545 · 10546 · 10547 · 10548 · 10549 · 10550 · 10552 · 10553 · 10560 · 10562 · 10566 · 10567 · 10570 · 10573 · 10576 · 10577 · 10578 · 10580 · 10583 · 10588 · 10589 · 10590 · 10591 · 10594 · 10595 · 10596 · 10597 · 10598 · 10601 · 10603 · 10604 · 10605 · 10606 · 10607 · 10701 · 10703 · 10704 · 10705 · 10706 · 10707 · 10708 · 10709 · 10710 · 10801 · 10803 · 10804 · 10805

Sources

  • Climate: NOAA NCEI U.S. Climate Normals 1991–2020, station USW00094745.
  • 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