22084mp4

: The hole should typically be three times the width of the post (e.g., a 12-inch diameter hole for a 4x4 post) to allow for sufficient concrete or gravel packing.

: In colder climates, posts must be set below the frost line —often 36 to 48 inches deep—to prevent "frost heaving," where the ground pushes the post out as it freezes and thaws. 22084mp4

If you are instead asking about the technical specifications for a "deep post" (as in a structural fence post): : The hole should typically be three times

: Most builders recommend burying one-third of the total post length in the ground. For a standard 6-foot fence, the post should be at least 2 feet deep. 22084mp4