Frost Line Depth in Nassau County, New York
- 1 verified code nearby
- Checked Oct 2026
No official local value
No official frost line depth is published for Nassau 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: 83 nights a year at or below 32 °F (NOAA 1991–2020, Mineola, 1.5 mi).
Checked Oct 2026. Report a correction
Does Nassau County have an official frost line depth?
No adopted frost line depth found for Nassau 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 Nassau County’s own number.
What frost line depth does Nassau 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 Nassau County?
Drawn with the deepest nearby official value (42 in). Confirm Nassau County’s own depth before you dig.
House or garage footing in Nassau County: dig at least 42 in (107 cm). Below the frost line and at least 12 in deep (IRC R403.1.4).
| Project | Depth | Rule |
|---|---|---|
| House or garage footing | 42 in | Below the frost line and at least 12 in deep (IRC R403.1.4) |
| Deck footing (attached) | 42 in | Below the frost line and at least 12 in deep (IRC R507.3) |
| Water service line | 48 in | 6 in below the frost line and at least 12 in deep (IRC P2603.5) |
| Fence post bottom | 42 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 Nassau County?
- J
- F
- M
- A
- M
- J
- J
- A
- S
- O
- N
- D
Average lows are at or below freezing from Jan to Feb. 83 nights a year reach 32 °F or colder; Jan is coldest, with an average low of 27.2 °F.
NOAA 1991–2020 climate normals, Mineola station, 1.5 mi away, elevation 96 ft.
Monthly temperatures as a table
| °F | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Low | 27.2 | 28.2 | 34.5 | 43.3 | 52.2 | 61.5 | 67.7 | 66.1 | 59.8 | 49.2 | 39.8 | 32.6 |
| High | 41.6 | 44.1 | 51.1 | 62.1 | 71.9 | 80.9 | 86.5 | 84.5 | 77.5 | 66.7 | 55.9 | 46.5 |
Nassau County has fewer freezing nights than 61 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 Nassau County use?
One official code near Nassau County is verified.
| Place | Verified frost line | Distance |
|---|---|---|
| Mount Vernon | 42 in | 18 mi away |
How likely is the soil in Nassau County to heave?
USDA rates the sampled soil around Nassau County as 100% moderate for frost action (main soils: Hempstead, Riverhead).
USDA NRCS soil survey, 9 sample points within 2 mi. Higher frost action means more risk of heave; see frost heave.
Nassau County at a glance
- Frost line depth
- No official local value
- Population (2023 est.)
- 1,381,715
- Mean annual temperature
- 55.5 °F
- ZIP codes (70)
- 11001 · 11003 · 11010 · 11020 · 11021 · 11023 · 11024 · 11030 · 11040 · 11042 · 11050 · 11096 · 11501 · 11507 · 11509 · 11510 · 11514 · 11516 · 11518 · 11520 · 11530 · 11542 · 11545 · 11547 · 11548 · 11549 · 11550 · 11552 · 11553 · 11554 · 11556 · 11557 · 11558 · 11559 · 11560 · 11561 · 11563 · 11565 · 11566 · 11568 · 11569 · 11570 · 11572 · 11575 · 11576 · 11577 · 11579 · 11580 · 11581 · 11590 · 11596 · 11598 · 11709 · 11710 · 11714 · 11732 · 11735 · 11753 · 11756 · 11758 · 11762 · 11765 · 11771 · 11783 · 11791 · 11793 · 11797 · 11801 · 11803 · 11804