Frostline.info

Frost line depth in Sullivan County, New York

Frost reaches about 37 inches in typical soil across Sullivan County, from 33″ in the mildest ZIP code to 39″ in the coldest. Codes in this climate commonly set footing depth at 30 to 48 inches.

Deep frost
Estimated frost depth
37″
typical silt/loam soil
Typical code footing depth
30–48″
rule of thumb for this climate
Design freezing index
1,390
°F-days, 100-year winter
ZIP codes covered
45
#31 of 62 counties in NY (1 = deepest)
37″ 0″12″24″36″48″60″ ground frozen
Est. frost (typical soil) Typical code footing depth Clay–sand range

Frost depth by soil type

Soil typeEst. frost depth
Sand / gravel (drains well)46″
Silt / loam (typical yard soil)37″
Clay (holds water)32″

County average. Methodology.

Verify before you dig. These are climate-based estimates. The legally required frost depth is the figure your building department publishes in its IRC Table R301.2 (climatic and geographic design criteria). Call the Sullivan County building or permitting office in New York and call 811 before digging.

Frost depth by ZIP code in Sullivan County

ZIPCityEst. frostCode range
12701Monticello36″30–48″
12719Barryville34″30–42″
12720Bethel37″30–48″
12721Bloomingburg34″30–42″
12723Callicoon38″30–48″
12726Cochecton38″30–48″
12727Cochecton37″30–48″
12732Eldred34″30–42″
12733Fallsburg37″30–48″
12734Ferndale38″30–48″
12736Fremont Center39″30–48″
12737Glen Spey33″30–42″
12738Glen Wild36″30–48″
12740Grahamsville36″30–48″
12741Hankins38″30–48″
12742Harris38″30–48″
12743Highland Lake34″30–42″
12745Hortonville38″30–48″
12747Hurleyville38″30–48″
12748Jeffersonville38″30–48″
12750Kenoza Lake38″30–48″
12751Kiamesha Lake37″30–48″
12752Lake Huntington37″30–48″
12754Liberty38″30–48″
12758Livingston Manor38″30–48″
12759Loch Sheldrake38″30–48″
12762Mongaup Valley38″30–48″
12763Mountain Dale36″30–48″
12764Narrowsburg37″30–48″
12765Neversink37″30–48″
12766North Branch38″30–48″
12768Parksville38″30–48″
12770Pond Eddy33″30–42″
12775Rock Hill35″30–42″
12776Roscoe38″30–48″
12777Forestburgh34″30–42″
12779South Fallsburg37″30–48″
12783Swan Lake38″30–48″
12786White Lake37″30–48″
12787White Sulphur Springs38″30–48″
12788Woodbourne37″30–48″
12789Woodridge37″30–48″
12790Wurtsboro34″30–42″
12791Youngsville38″30–48″
12792Yulan34″30–42″

What this means for your project in Sullivan County

Deck footings & piers

Footings must bear below the frost line and at least 12″ below undisturbed ground. For planning in this area, budget for holes around 48″ deep until your permit office confirms the exact figure.

Fence posts

Set posts at least one-third of their above-ground height. Where frost heave is a problem, carry concrete footings below the frost line (about 37″ here in typical soil) and bell or taper the bottom.

Water & irrigation lines

Bury supply lines below the frost depth. Your water utility or plumbing code sets the minimum cover; in a climate this cold, 4 feet or more is common for service lines.

Slabs & frost-protected foundations

Frost-protected shallow foundations (IRC R403.3) use the 100-year air freezing index — 1,390 °F-days here — to size perimeter insulation, letting footings sit shallower than the frost line.

Weather stations used

NOAA weather stationDistance100-yr AFI
Liberty, NY7 mi1,515
Port Jervis, NY23 mi990
Mohonk Lake, NY33 mi1,109
Pleasant Mount 1 W, PA34 mi1,674

Nearby counties

Common questions

What is the frost line depth in Sullivan County?

About 37 inches in typical soil, based on NOAA's 100-year air freezing index. Across the county's ZIP codes the estimate runs from 33 to 39 inches.

How deep should footings be in Sullivan County, New York?

Codes in climates like this commonly require 30 to 48 inches. The Sullivan County building department publishes the required frost depth in its adopted code (IRC Table R301.2).

Does frost depth vary within Sullivan County?

Yes. Estimates differ by 6 inches between the coldest and mildest ZIP codes, mostly from latitude and elevation. Check your own ZIP below.