Frost line depth in Coos County, NH

How deep the ground freezes in Coos County, NH

54 in. Dig to 54 in, just below the frost. Nearest NOAA station: Berlin Muni Ap, 7.6 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