Post Ankers

[idaho04]

I want to build several 12'x16' bays (loafing sheds, 4 post flat slant roof open front) for equipment storage behing my shop. The theory was: make holes, install PT posts (4x6?), and pour cement.

Now, the cement delivery is expensive (20 holes) or lot of work (sand, mixing). I was thinking if there are some pre made cement footing/foundation cones to burry in the ground with attach hardware for the posts. Any ideas as of availability and experiece with such things?

[jimbrown]

Well here is what I do and it seems to work well for me.
I dig the hole, put about two inches of gravel in the bottom, set in the post. Fill in around the post with dry ready mix or dry post mix. I tamp the dry mix a couple of times while I am filling the the hole. It is much easier to work with the dry mix and the mositure in the ground will set it up in a couple of weeks. I suppose you could wet it after they were in but I don't. I have a 4 stall mare motel with breeze way that I did that way about three years ago and it has stood up to our high winds and dust devils with no sign of coming down. Not counting the horses leaning on it also.

[Bird]

Jim, I've also done almost the opposite; i.e., I've set the post in the hole, dumped in a bucket of water, then dumped in a bag of sakcrete, mixed it a bit simply by working a rod up and down around the post, and quit there.

[Pat]

Bird, Not everyone has dirt as dry as yours. I prewet my holes if there isn't much soil moisture so it won't take so long for the cement to react but not if the dirt is very damp (too lazy to tote water very far if not really needed.) I have seen guys building miles of fence and using sack-crete for the many stretch fixtures and corners and the only water was in the cooler on the back of the truck for drinking. It used to bother me that I wasn't correctly mixing the concrete for posts and fixtures but I got over it.

Pat

[MadMike]

Does the concrete have to completely fill the hole or does it just need a footing below the frost line? If so how deep of a footing does it need.

[Pat]

Mike, Frost line depth varies. Whatever is CODE in your area is probably safe.

Concrete in the bottom of the hole is often enough. I often use 3 ft deep 12 inch diameter holes for 2 3/4 or 2 7/8 pipe when a 9 inch auger would be ample to satisfy a lot of folks. The concrete shrinks when it cures so it grabs the pipe pretty well. If you tamp the dirt (say, 4 inches at a time) when you backfill then the larger diameter (12 inch) "washer" of concrete will resist tilting or coming up better than a smaller hole with more height of concrete.

Pat