Frostline.info

Frost line depth in Jackson County, Missouri

Frost reaches about 30 inches in typical soil across Jackson County. Codes in this climate commonly set footing depth at 24 to 36 inches.

Moderate frost
Estimated frost depth
30″
typical silt/loam soil
Typical code footing depth
24–36″
rule of thumb for this climate
Design freezing index
918
°F-days, 100-year winter
ZIP codes covered
54
#51 of 115 counties in MO (1 = deepest)
30″ 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)38″
Silt / loam (typical yard soil)30″
Clay (holds water)26″

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 Jackson County building or permitting office in Missouri and call 811 before digging.

Frost depth by ZIP code in Jackson County

ZIPCityEst. frostCode range
64014Blue Springs30″24–42″
64015Blue Springs30″24–36″
64016Buckner31″30–42″
64029Grain Valley31″24–42″
64030Grandview29″24–36″
64034Greenwood30″24–36″
64050Independence30″24–42″
64052Independence30″24–36″
64053Independence30″24–42″
64054Independence30″24–42″
64055Independence30″24–36″
64056Independence31″24–42″
64057Independence30″24–36″
64058Independence31″24–42″
64063Lees Summit30″24–36″
64064Lees Summit30″24–36″
64070Lone Jack31″24–42″
64075Oak Grove31″24–42″
64081Lees Summit30″24–36″
64082Lees Summit30″24–36″
64086Lees Summit30″24–36″
64088Sibley31″30–42″
64101Kansas City30″24–36″
64102Kansas City30″24–36″
64105Kansas City30″24–36″
64106Kansas City30″24–36″
64108Kansas City30″24–36″
64109Kansas City30″24–36″
64110Kansas City29″24–36″
64111Kansas City30″24–36″
64112Kansas City29″24–36″
64113Kansas City29″24–36″
64114Kansas City29″24–36″
64120Kansas City30″24–42″
64123Kansas City30″24–42″
64124Kansas City30″24–42″
64125Kansas City30″24–42″
64126Kansas City30″24–36″
64127Kansas City30″24–36″
64128Kansas City30″24–36″
64129Kansas City29″24–36″
64130Kansas City29″24–36″
64131Kansas City29″24–36″
64132Kansas City29″24–36″
64133Kansas City29″24–36″
64134Kansas City29″24–36″
64136Kansas City30″24–36″
64137Kansas City29″24–36″
64138Kansas City29″24–36″
64139Kansas City30″24–36″
64145Kansas City29″24–36″
64146Kansas City29″24–36″
64147Kansas City29″24–36″
64149Kansas City29″24–36″

What this means for your project in Jackson 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 36″ 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 30″ 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 — 918 °F-days here — to size perimeter insulation, letting footings sit shallower than the frost line.

Weather stations used

NOAA weather stationDistance100-yr AFI
Olathe 3 E, KS19 mi824
Harrisonville, MO26 mi927
Leavenworth 3 S, KS29 mi1,015
Lexington, MO33 mi1,040

Nearby counties

Common questions

What is the frost line depth in Jackson County?

About 30 inches in typical soil, based on NOAA's 100-year air freezing index. Across the county's ZIP codes the estimate runs from 29 to 31 inches.

How deep should footings be in Jackson County, Missouri?

Codes in climates like this commonly require 24 to 36 inches. The Jackson County building department publishes the required frost depth in its adopted code (IRC Table R301.2).

Does frost depth vary within Jackson County?

Very little. Estimates across the county stay within 2 inches. Soil type matters more than location here.