Locust for main poles for barn?

[MILL BRANCH FARMS]

would i be crazy to use locust for the main poles in a pole barn? 13' with 3' buried? would i be better off pouring concrete piers above grade and set poles on that? or just go with store bought treated 6"x6"?

[beenthere]

What are your cost comparisons?
What are your lifetime expectations?

How much overhang (or how dry do you think you can keep the poles if they are in the ground) ?

Don't think you are crazy.  ;)

[Satamax]

They could last 50 years, or they could last 10. Depending on what bugs are in the ground, bacterias, fungus etc. And also the drainage  and acidity of the ground. Go for concrete piers. They don't take much to do. Put a U shaped piece of rebar in them, curve up. Do a mortice at the end of each post, put a bolt through all that. And put a bit of tar shingle or felt at the end of the post, to protect it from the lime and other components of the concrete. That for sure can last for 50 years. May be a hundred or more.

When you're talking about locust, we agree, on "robinia pseudoaccacia" ?

[Jay C. White Cloud]

I work in old barns all the time, mind you the wood is above grade (most of the time,) but there are techniques that can give you extended life to a wood species that is already rot resistant, like the Robinia genus.  If you take a small butane torch and scorch the portion of the wood to go into the ground, you will have extended the life span considerably.  Now you don't burn it but you do put a good char into it, which is pure carbon and that repels most organisms.

Add some bored/drilled in preservatives, oil with borates added painted on, keep your drip line of the roof at least a few feet away and back fill with big stone at the base (one under the post,) and packed 3/4 gravel around post (not dirt, clay or any soil-only stone); this will get you probably to the 100 year mark or longer.  There is evidence that some of these techniques have lasted 500 years or more.

http://www.logprorestoration.com/treatments.php

Regards,  jay

P.S.  You aren't crazy one bit...been done for thousands of years, most of us just forgot how to do it, that's all... ;) :D

[routestep]

Locust is a strong wood, but around here I've only seen a few that would make a long pole. Most have a bend or a twist in them.

[Jay C. White Cloud]

Bends and twist are o.k, often the wood is stronger for it.  You just need the joints to line up and there are layout methods for that, even on bent and bowed stuff.  No worries.

[MILL BRANCH FARMS]

The trees are free and close by. Jay: could I cut 'em, debark 'em, char 'em then bury 'em? or should I dry them first?

[Satamax]

Hey guys, i think the most rot resistant wood would be black locult dipped into home heating fuel oil for a while, then burned on the exterior, and painted with tar. If you can make that rot, you're skilled! ;D

[jueston]

The trees are free and close by. Jay: could I cut 'em, debark 'em, char 'em then bury 'em? or should I dry them first?

there is no way to effectively dry a whole tree or a timber of that size, so you can put it up an hour after you cut it if you can move it and debark it that fast.

[Jay C. White Cloud]

Hello, Satamax,

Tar can actually trap moisture inside wood, (kind'a like a plastic bag raped around the base.)  The surface wood won't rot because of the tar, but the inner wood does.

Of all the new methods out the water activated capsules I referenced earlier do the best job.  You combine the capsules with the traditional methods I described, and you could build a house, if you can get your building department to buy it, some do, some don't.

Hi M.B.F. (a.k.a. digger?),

No need to dry them at all brother. (those capsules are water activated.)  We work in green wood almost exclusively from furniture, floors to timber frames.  As long as you follow those steps I gave you, you should be golden ;D and shin'n bright.  Could almost guarantee you and I and our kid's won't be worry'n about rot in those post. Solid too, I've seen category 4 hurricanes strike the tip of Florida and flatten ever stick built house around with there fancy metal ties and gizmos, and what is standing strong in the back yard?  There pool cabana built "Chickee," style by the local  Choctaw and Seminole who have used these methods for centuries.

If you need help with layout of joints or anything, give a shout.  Center line layout will give you a strait line and a reference point for your work, and where to measure. Good luck, and show us pictures of your work.

Regards,  jay

[Jim1611]

I used black locust for fence post and have had some in the ground for 20 years and they show no sign of rotting. One thing that will make them rot quicker is to set them on concrete. If you tamp around them with gravel they'll last longer than in concrete. The concrete tends to keep water trapped between it and the post, gravel will let it get away. Although I would pour a concrete pad at the bottom of the hole for the post to sit on or lay a big flat rock at the bottom. One thing is for sure, your black locust poles will outlast the treated kind you can buy.

[tyb525]

Yes setting them in concrete is a sure fire way to get them to rot. Everything suggested about gravel and charring is good advice.

[LaserZX]

would i be crazy to use locust for the main poles in a pole barn? 13' with 3' buried? would i be better off pouring concrete piers above grade and set poles on that? or just go with store bought treated 6"x6"?

You are much better to dig below the frost line and pour a concrete post in the ground    It is best to use a cardboard cylinder  My best guess would be min
18" plus height above the ground level you chose. Approximate 2'   You will have a better foundation and piece of mind.   Redoing things cost so much more and time consuming.      I can see pole barn repair business booming in 20 years or so   Pouring a concrete post in place with premix will be very strong.  Consider 2500 psi 

[MILL BRANCH FARMS]

If I use concrete piers wouldn't I be able to use poplar or pine for poles since it would be above ground?

[Jay C. White Cloud]

Hi MBF,

Yes you could.  When I have facilitated similar architecture for clients, I ask them to consider all the variables as they apply to their needs.  Often what appears to be a good idea, as a whole, may not be.  You have to ask yourself what you want out of the buildings performance.

You know a hole has to be dug for either post type, whether wood in the ground or on concrete, and I would still recommend back filling the same way as I described before with the rocks and 3/4" gravel.  Soil often contains clay, some are even bentonite clay, which is where heaving comes from more so than frost ever could, so a gravel back fill is best. 

Compare your needs and the costs.

Purchase the best post moment connections you can afford, this is the week spot.

Regards,  jay

[Jim_Rogers]

Another method of making a foundation for a pole barn would be the "short pole" system.

There is a story I wrote about it here:

https://forestryforum.com/board/index.php/topic,20380.0.html

With a drawing.

Jim Rogers

[petefrom bearswamp]

I built a sugaring house in 1974 with 6x6 square sawed Black locust poles.
Was a bugger to drive nails into and I no longer live at this location, but I drive by often and the building is still there.
Backfilled the holes with the dirt from them.
pete

[Jim1611]

If you were to use the short post system and make the post that go into the ground out of hedge (Osage Orange) they'd last a lifetime, even in concrete. I know of some hedge post sat in concrete that are well over 50 years old and they show no sign of rotting. I also took a fence out on some property I bought and the hedge post were over 75 years old and I used them again.

[rooster 58]

    When my father and I started building pole buildings in the mid 70's, we were using poles treated with creosote. After 2-3 yrs., the newer CCA treated posts replaced the creosote poles.

     Our standard procedure was to dig the hole to 36" or so, then pour a 4" "footer" in the hole. If we were in a hurry we would use 1/2 of a 4x8 solid block in the bottom. But after we poured a concrete bottom, we would come back the next day and set the posts, then pour concrete around the posts up close to the top of the hole. We double checked the alignment of the post to make sure it was set accurately, then filled the rest of the hole with dirt to hold the post in place until the concrete dried. This made a very sturdy foundation to work on, without having to worry about ladders or anything pushing the post all over, and made it alot safer; especially on taller buildings.

     To this day, I'm not aware of any of our buildings failing to post rot. They all stand straight, square, level, and plumb

[Jay C. White Cloud]

I can speak to Rooster 58's observation.  Once the building is complete, it preforms very much like a traditional barn setting on a dry laid foundation.  Put simply, it is just setting there by it's own weight.  At least once a year, on average, we will find a barn that has a "pole barn" ell attached to a side or end.  These are often from the 70's or 80's and have Creosote or PT posts set into concrete, (some are just in packed stone.) 

We can just push them over as most have either completely rotted at the concrete to wood interface or they snap easily at the junctions do to degradation.  They seem to decompose as quick or quicker than if back filled with dirt.  On the rare occasion that we find a pole building that someone made the effort to pack stone around and under the base.  They are as solid and look as new as the day they when in.  Moisture rots wood, it is simple as that and concrete encapsulated wood rots the fastest, I see it all the time.  Not as often but we even find it in the interior post if there is a lot of ground moisture or water spray down used inside a barn.

[rooster 58]

     Jay, you probably have a valid point as I have not really had the perchance to go back and look at or excavate any I have not seen any sign of sinking posts due to rot. It doesn't take much settling to show up in an eave or ridge line.

[Jay C. White Cloud]

Hi Rooster58,

After I made my post I wanted to edit it to say I wasn't being critical of what you did, so many do it that way.  I have been able to take some of these pole buildings and flip them over like a big card board box, they are so well built, just like the traditional barns they had been attached to.  So I'm sure your barns had been well built. 

It even goes to a point I have been trying to make to PE for years, that just setting a building on the ground is often enough.  You don't need to tie them down and worry so much about it.

I wish I had pictures but we are going back to 1969 or so.  In the pan handle of Florida to Louisiana,  I've seen beautiful traditionally built houses that just sat on a rock or Cypress stump.  They had huge porches that ran all the way around them, Grammy called them "hurricane," porches, because you could go out in a storm and walk all the way around the house without getting in the wet of the storm.  If the wind was bad enough, up in the attic was old shrimp nets that would go over the roof in bad hurricanes and get tied down to "dead man" anchors buried around the house about every spot there was a porch post.  These anchors could be anything from a ceder stump to an old ship engine block/anchor with a length of chain attached.  These old buildings, in the heart of hurricane country, just sat on their foundations, and had for a couple hundred years.  All the modern stuff gets blown to "kingdom come," but not these old Cajun houses. Not until some "wise a_ _," comes along and decides, "that won't work, I can build it better than that,..."  seldom do I see real or actual improvement over traditional building methods, often the case is opposite.

I was corresponding with a historical restoration gentleman a few years back, that also had a solid Engineering back ground.  He observed that if you got a wind high enough to tip most old building over or rip off there roofs,  that the storm was going to cause damage no matter what you did to prevent it.  Short of living in a steel and concrete bunker or under ground, when Mother Nature gets her self all worked up about something, you ain't stopping her from terry things apart, and most modern fixes are aesthetically unpleasing, not that much more functional (often less so,) than what I forbears did to deal with a problem, and really just somebodies way to try to reinvent the wheel and make a few dollars in the process.

[rooster 58]

    Thanks Jay. The one thing that pole buildings can be vulnerable to is wind, aqt least pertaining to shear forces. The weakest part of the post and the place it is most likely to fail is at the ground, or; where it is fastened to a pier. This does not usually occur unless the building is left open, either by design or by mechanical doors left open; which can permit a strong wind to enter, creating uplift on a roof system and destroy sidewalls particularly.

   I once saw a machinery shed, approximately 40x80x14 that was devastated by such a wind or probably more likely a microburst. The building had three sides, with the open side facing a long gentle down slope. The farmer said it was a tornado, but I'm betting it was a microburst. The roof/ truss system was largely in one piece, but laying about 150 feet behind the "closed" sidewall. That sidewall was pushed over backwards and laying on the ground. The posts had failed at ground level. The two endwalls were upright but leaning back probably 20* from plumb

[S.Hyland]

I agree that if you can create good drainage, the posts will last. I'm guessing that local soil conditions play a large part in the success of that approach. For example, in my area it's nothing but clay. There is practically no percolation. In that case I would guess the only way make wood work in the ground truly long term would be some sort of footer drain. Which would defeat the simplicity aspect...

[Jay C. White Cloud]

Hi S.Hyland,

You have brought up an important point that should be part of this thread post, clay soils.  You always here or read about being below your regions "frost line," and many years ago I questioned several "old timers," about just that.  They all said it was not there main concern, soil type was. If a soil is well drained you don't get frost heave at all.  I really began to understand this when I noted that "rock cairn," markers sat directly on the ground and would have tumbled over if the ground heaved to much.  Then as I began looking at vintage footers of buildings I worked on, I noted that if the ground was gravel or sand based, plinth footers would just be set directly on mineral soil not anywhere near being below "frost line," but if the soil had a heavy clay content, the footers would go deep and/or be fill with stone and/or gravel.  When I started to read about clays, I learned that some types like bentonite expand way worse than frost or ice, just by being wet.  If you freeze soil containing this clay it is disastrous for a foundation, even some below frost line if the bentonite content is too high.  So I've stopped worrying about frost and look at my soil types and good drainage.  "Gravel trench" and "gravel pad" foundations can't be beat.

Regards,  jay