Frost line depth in Carter County, MT

How deep the ground freezes in Carter County, MT

47 in. Dig to 48 in, just below the frost. Nearest NOAA station: Ridgeway 1 S, 3.4 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