Frost line depth in Mercer County, NJ

How deep the ground freezes in Mercer County, NJ

19 in. Dig to 19 in, just below the frost. Nearest NOAA station: Trenton State College, 4.7 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.

Code depth · Snow