Frost line depth in Douglas County, IL

How deep the ground freezes in Douglas County, IL

27 in. Dig to 28 in, just below the frost. Nearest NOAA station: Tuscola, 4.1 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