Need help with pole barn footer

[76cruiser]

All,

I am working with a contractor and trying to decide how to embed the posts in my soon to be built barn. I asked him if I should use the precast footers (concrete cookies). He said if I supply them he will put them in. He also said just add quickrete.. but it is my call.

The precast footers have proven the be difficult to find. I found one supplier 2.5 hours away but they are only 14" diameter by 4" thick. My hole will be 18" by 4' deep.

Any advice from the group my soil is pretty good 3000 psi or better? I have heard some say that quickrete causes the posts to degrade faster. I also considered doing them both (precast footer AND quickrete). I know a poured footer would be nice, but cost prohibitive in my case. I will be using rebar in the posts for uplift protection.

Any advice would be welcomed!

 

[kbs2244]

IMHO the advice of an experienced local guy that knows local soil an wind conditions should be followed.
He has a reputation to protect and is unlikely to give bad advice.

But if you want to do some second guessing...

http://www.countryplans.com/foundation/index.html

http://www.pole-barn.info/pole-building-construction.html

http://www.easybuildings.com/

https://www.permacolumn.com/home

 

[cyamaha2007]

I dig my holes, clean them out. Tamp the bottom. Pour 6in of mixed quickcrete in the hole. Drop some wire mesh or rebar in the wet concrete. Lightly vibrate the concrete(use a palm sander attached to a piece of black iron pipe). Let the concrete set for 8hrs. Now drop post in hole. Brace post in plumb. Slowly add 4in of chat(very fine sharp gravel). Now tamp the chat until compacted. Continue adding 4in of chat and tamping until the hole is full. If the chat isnt packing tight add a little water. Whatever you do dont imbed the post in concrete. It will drastically shorten the life of your building. You can look at my build below for some pics of the process.

 

[REPO]

Everything I have ever been told is that concrete and wood don't mix. If you put a concrete little pad (foot) at the bottom it's basically going to be a sponge and will hold water. Our local builders suggest (and use) 3/4" washed crush both at the bottom of the hole and around the posts. This lets the water run away from the posts and lets them breath. But remember, it has to be washed as any dirt or sand in it will defeat the purpose.

 

[Big Bad Dad]

On mine, I augered 24" round holes to below the frost line. (18" here) The code requires 8" thick concrete. I put a very heavy coating of black roofing tar / foundation coating on the bottom of the posts to up above the planned finish floor level. Then I backfilled around the posts with a mix of crushed stone (57's) and the some of the original red clay dirt to allow for some drainage. I ran some 3/8 by 6" lag bolts into the posts to help set the floor rebar on. Poured the concrete floor around the posts. That way, my posts were protected from ground moisture, and I felt the weight of the concrete floor tied to the posts with the lag bolts would help hold everything together in the event of high winds. Been good for 12 years so far.....