Frostline.info

Frost line depth in Wayne County, Michigan

Frost reaches about 35 inches in typical soil across Wayne County, from 33″ in the mildest ZIP code to 37″ in the coldest. Codes in this climate commonly set footing depth at 30 to 42 inches.

Deep frost
Estimated frost depth
35″
typical silt/loam soil
Typical code footing depth
30–42″
rule of thumb for this climate
Design freezing index
1,242
°F-days, 100-year winter
ZIP codes covered
69
#82 of 83 counties in MI (1 = deepest)
35″ 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)44″
Silt / loam (typical yard soil)35″
Clay (holds water)30″

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 Wayne County building or permitting office in Michigan and call 811 before digging.

Frost depth by ZIP code in Wayne County

ZIPCityEst. frostCode range
48101Allen Park35″30–48″
48111Belleville36″30–48″
48120Dearborn34″30–42″
48122Melvindale35″30–42″
48124Dearborn35″30–48″
48125Dearborn Heights35″30–48″
48126Dearborn34″30–42″
48127Dearborn Heights35″30–42″
48128Dearborn34″30–42″
48134Flat Rock36″30–48″
48135Garden City36″30–48″
48138Grosse Ile36″30–48″
48141Inkster36″30–48″
48146Lincoln Park35″30–42″
48150Livonia35″30–48″
48152Livonia37″30–48″
48154Livonia36″30–48″
48164New Boston37″30–48″
48168Northville36″30–48″
48170Plymouth36″30–48″
48173Rockwood36″30–48″
48174Romulus36″30–48″
48180Taylor36″30–48″
48183Trenton36″30–48″
48184Wayne36″30–48″
48185Westland36″30–48″
48186Westland36″30–48″
48187Canton35″30–48″
48188Canton36″30–48″
48192Wyandotte35″30–42″
48193Riverview36″30–48″
48195Southgate35″30–48″
48201Detroit33″30–42″
48202Detroit33″30–42″
48203Highland Park34″30–42″
48204Detroit34″30–42″
48205Detroit33″30–42″
48206Detroit34″30–42″
48207Detroit33″30–42″
48208Detroit34″30–42″
48209Detroit34″30–42″
48210Detroit34″30–42″
48211Detroit33″30–42″
48212Hamtramck33″30–42″
48213Detroit33″30–42″
48214Detroit33″30–42″
48215Detroit33″30–42″
48216Detroit33″30–42″
48217Detroit35″30–42″
48218River Rouge34″30–42″
48219Detroit35″30–42″
48221Detroit34″30–42″
48223Detroit35″30–42″
48224Detroit33″30–42″
48225Harper Woods33″30–42″
48226Detroit33″30–42″
48227Detroit34″30–42″
48228Detroit34″30–42″
48229Ecorse35″30–42″
48230Grosse Pointe33″30–42″
48233Detroit35″30–42″
48234Detroit33″30–42″
48235Detroit34″30–42″
48236Grosse Pointe33″30–42″
48238Detroit34″30–42″
48239Redford35″30–42″
48240Redford35″30–42″
48242Detroit36″30–48″
48243Detroit33″30–42″

What this means for your project in Wayne 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 42″ 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 35″ 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 — 1,242 °F-days here — to size perimeter insulation, letting footings sit shallower than the frost line.

Weather stations used

NOAA weather stationDistance100-yr AFI
Grosse Pointe Farms, MI16 mi1,116
Ypsilanti East Mich U, MI22 mi1,250
Pontiac State Hospital, MI23 mi1,350
Willis 5 Ssw, MI26 mi1,543

Nearby counties

Common questions

What is the frost line depth in Wayne County?

About 35 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 37 inches.

How deep should footings be in Wayne County, Michigan?

Codes in climates like this commonly require 30 to 42 inches. The Wayne County building department publishes the required frost depth in its adopted code (IRC Table R301.2).

Does frost depth vary within Wayne County?

Very little. Estimates across the county stay within 4 inches. Soil type matters more than location here.