Frost line depth in Isabella County, MI

How deep the ground freezes in Isabella County, MI

35 in. Dig to 36 in, just below the frost. Nearest NOAA station: Central Michigan Univ, 5.4 mi.

Your building department sets the legal frost line depth (IRC Table R301.2(1)); footings must go below it (R403.1.4.1). Call them before you dig.

Code depth · Snow