Frost line depth in Porter County, IN

How deep the ground freezes in Porter County, IN

29 in. Dig to 30 in, just below the frost. Nearest NOAA station: Valparaiso Wtr Wks, 1.7 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.