small pole bldg advice needed

Don't like wood _in_ concrete here as it rots the wood off, unless you just mean a doughnut at the bottom.

4x4 - which is really 3.5 x 3.5 of poor ringed wood these days - is not near strong enough for a 12 foot sidewall.

--->Paul

FWIW, my 36 X 36' pole barn was built with 8X8's, sunk into 4' deep holes about 3 ft. in diameter with concrete. Metal siding. Eaves are 10', I wish they were 12. Contractor left it with dirt floor. I shopped around for a concrete contractor and bids from about a dozen contractors ranged from $2,600 to $5,700. Selected the second lowest contractor based on reputation & they did a great job. Location is western Oregon, so we weren't building for a hurricane.

First, 4x4s are too light for a building of that size, particularly with 12' sidewalls. Your posts not only have to handle wind load (shear), they also carry the entire weight of the building (compression). 6x6s might be overkill, but 4x6s will be about twice as stiff as 4x4s. 4x6s only about 50% more than 4x4s, so they're a lot easier to handle.

I like the idea of making your own laminated posts. The big advantage of laminated posts is that they are straighter than solid posts. Even on my 10' sidewalls, several of the posts were so crooked and twisted that I had to notch them so my girts would be reasonably straight.

As others have said, your posts need go below the frost line. Also, they need to be on (not IN) a concrete pad. The pads need to be at least six inches thick and a foot in diameter, more if they're in soft ground. When you backfill the holes, start with a few inches of gravel to ensure drainage around the post.

Call in all your favors, get some buddies to help you with the posts, trusses and concrete. Of course you'll have to return the favor for all of their buildings, but that's how it goes.

Good luck,

Bill

Check out lesterbuildings.com, I believe this is how they make their posts. You may have to poke around on the site, but I believe they show a photo of how the posts are made.

From my perspective, as a non-engineer, I'd say have been using 2x4's to build homes at 24" spacing for ions, and those homes stand for ions. I'd like to be able to say "yes" to your question, but an engineer I am not. I have 2x8 rat board around my base that formed the concrete. And I have 2x4's spaced every 2' up, starting from the ground, working towards the top. And of course by the time you mount your trusses across the top, will strengthen even more.

Can tell you this for sure. Is a fella a few miles down the road whom put one up as you described, using 4x4s at 8' spacing, but about 10' on the wall heighth, and came out just fine. His looks just fine, and works just fine. Make extra sure you're square. Use treated lumber into the ground. And if you think or figure need 8' wide doors, go at least 10', if need 10' wide, go at least 12' - cause it's a pain in the butt when the tractor axle squeaks through by a few inches (and the duals aint even on yet), then you gotta take some down, widen the door opening, then make a wider door from what you took down. Who was the idiot that overlooked that - ME, MYSELF, and I, both doors.

Don't forget to check with your code guy first. But I don't see a problem. Good luck.

Mark