Frost line depth in Winnebago County, IL

How deep the ground freezes in Winnebago County, IL

36 in. Dig to 36 in, just below the frost. Nearest NOAA station: Rockford Gtr Rockford Ap, 10.6 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