Square or Round poles for pole barn

[MG44]

You will be much happier with square posts. Good choice.

 

[Mike in Ohio]

Were told you 8x8 by an engineer or code inspector or by a bunch of cranky guys on the internet?

I am in Ohio. When I originally built mine 12 feet tall I used 6x6 in the corners and on each side of the 16' door (bearing wall). 4x6s for the rest of the posts. I am on clay soil. Posts are about 30" deep with 10-12 inches of concrete under them to be below the frost line.

Not saying your code doesn't require 8x8 it just seems a bit much.

The round posts will be more work but oftentimes we do it yourselfers do have to trade our labor for money savings when the budget is tight.

Have fun with your build and don't get too wound up by some of the guys here almost all of them mean well, but humor and sarcasm sometimes loose something in the typing!

Who told you ?
I am in central N.Y. and built a 14' high 30" X 56" on clay soil from a kit with plans with 6" x 6" solid posts . no problems

8"x8". Probly more for wind loads in Florida.

Whether or not he needs 8x8 posts I don't know. It could be a possibility due to Florida getting hurricanes, like parts of Cali needing certain building specs due to earthquakes.

I hadn't thought of hurricane wind loads, but wouldn't you address that with the cross bracing and maybe some diagonal bracing? I am by no means an engineer so I am not setting up as an expert.

As a mildly amusing aside, when I built mine I used 2x4 girts with 7/16 osb then vinyl siding. I had a heck of a time convincing my dad ( a retired accountant and auditor) that yes 6 or 8 nails is all you need to hold the osb on to the 2x4s, but the nailing plan is because that osb is also what keeps the whole building from moving with the wind. Finally nailed 4 scrap 2x4s together into a square using 1 nail at each corner and then racked it out of square. Then I nailed a scrap piece of osb on the square and showed him the difference in strength.

 

[Sureshot]

A friend built a machine shed with round and put all the taper to the inside. All the bottoms and tops are aligned and vertical. If any poles had a bow he turned them to be "flat to the outside. It looks good on the outside but you would never want to try to finish it inside, well I wouldn't anyway.

Even going with solid 6x6 I would do my corners and beside the overhead doors with laminated posts. Corners could be done if you get some nice straight ones but............

 

[Lippyp]

I have a book on pole buildings and they were saying that using uncut timber (just good round poles) is way stronger than a squared off timber as the tree has all the structural fibres needed to resist the wind forces in the outer layers of wood just below the bark. Cut that off to square it up and you lose some of the inherent strength. As to the taper it depends how tall at the eaves you are going, over 8' the poles I'm looking to use don't taper that much, certainly not enough that a few minutes with a chainsaw and chisel to notch it slightly lower down won't cure.