PSA: A landscaper in line at the hardware store changed my mind about post hole depth

I was getting concrete last week and heard a guy ahead of me tell the clerk, 'I tell my fence guys to go 36 inches for a 6-foot post, no matter what the soil looks like.' I always went with 30 inches in our clay-heavy ground, thinking it was enough. After that, I looked it up and found a study from a state university saying frost heave can still pull up posts set at 30 inches in my area. Now I add that extra half-foot of depth on every job. Has anyone else had to adjust their standard depth after learning something new?

3 comments

3 Comments

elizabeth_chen811mo ago

That extra half-foot is a game changer in clay. Always better to overdo it than watch a whole line of posts tilt over the winter.

rowangonzalez1mo ago

Actually need a full foot in clay, not just a half. Frost heave will still get you.

lily892d ago

Feel your pain on the clay soil. I had to redo a whole section of my own fence after a bad winter taught me the same lesson. That extra digging is a pain but it saves so much trouble later.