Frost line depth in Missoula County, MT

How deep the ground freezes in Missoula County, MT

31 in. Dig to 31 in, just below the frost. Nearest NOAA station: Missoula 2 Ne, 9.6 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