Frost line depth in Philadelphia County, PA

How deep the ground freezes in Philadelphia County, PA

15 in. Dig to 16 in, just below the frost. Nearest NOAA station: Phila Franklin Inst, 4.1 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