Am I the only one who sets posts in concrete the wrong way

I keep seeing guys dump dry mix in the hole and add water after, but that leaves air pockets and the post rots faster after like 2 years. I started mixing it in a wheelbarrow first and tamping it down every 6 inches, has anyone else had theirs shift later doing it the dry way?

3 comments

3 Comments

craig.tessa1mo ago

My uncle put up a mailbox post back in '97 using that dry mix method and it's still standing straight, no rot, so I think a lot depends on your soil type and drainage honestly. If you're in heavy clay like I am, the dry mix actually creates a little barrier that sheds water away from the wood, but in sandy soil it just crumbles apart. I always do the pre-mix and tamp thing myself (feels more solid), but the rotting issue might be more about whether you used pressure-treated wood or not. The air pockets thing is real, but I've seen rot happen just as fast in perfectly mixed concrete if the post wasn't set on a gravel base.

cameroncarr1mo ago

Read somewhere that the dry mix method works because it lets the concrete cure slowly by pulling moisture from the ground, which actually makes it stronger in the long run. @craig.tessa, your uncle's setup makes sense if the clay holds that moisture just right, but I've heard stories of people in sandier areas having the whole thing crumble after a couple hard freezes. Always figured a little gravel base underneath is the real secret regardless of how you mix it.

barbara841mo ago

Yeah that gravel base thing is something I wish more people talked about. My dad lost a fence post in two years because he skipped that step, and the concrete just heaved right up on him during the first frost. It's frustrating when you follow one piece of advice and miss the little detail that actually saves the whole project.