Pole Barn, Pole Question

[HoustonBrama]

Thanks for the answers guys. I knew there had to be a reason why not to use the nail-lam. I never thought about the treatment percentage. I'll have to do some searching when I get home. I need some 20' poles. The lumber yards around only sell 12'. They may be able to order them though. Thanks again.

 

[jdmar]

The 6 x 6 seem to be straight...seems like they use the center of the tree and not an off-center cut--I guess that allows more equal expansion/contraction with moisture changes. I just placed some 16 foot ones that were very straight. I had the same concern as you but they were perfect. I realize 20' is even harder to get straight.

Also, be careful about the type of pressure treating you get. I have been told by several local goat and sheep farmers (inlaws included) that the new ACQ has too much copper and can be dangerous or even fatal to goats/sheep. I got the older CCA for this reason. Lumber yard said the same. I do NOT know if it is true or an old wive's tail, but I figure I would stick with the CCA. They were also a fair amount cheaper!

Hope your project goes well, keep us posted.

Peter

 

[Grand_Pooba]

Some of the builder in my area have been using PT poles that only stick out of the ground about 4' and have staggers or rabbits cut into the sides. The non treated lam beams are attached to these so they don't come into contact with the ground. It also allows them to better "plumb" the lam poles as they attach them. I've seen a couple Morton buildings going up this way.

 

[ray66v]

I specified the laminated 4x6 poles for my 1.5 story barn.

Besides being dead straight, and that they will stay that way in the future. There is another advantage, they will not shrink like the solid treated ones.

 

[HoustonBrama]

Pooba, are you saying the guys are using like 6"x6" by about 8' solid posts sunk say 4' in the ground then mortise the top part to add regular 2x lumber? This is a good idea. I had not thought about that.

 

[uphill]

The "old" carpenters I worked with as a young man always used pressure treated posts when contacting the ground, then painted the post with roofing tar, and finally rapping the tar portion with roofing felt. They said it kept the roofing tar from drying out over the years. I know it works because I've removed posts that have been dressed in this manner and the tar was still gooey and could still make a mess!

 

[Grand_Pooba]

Houston,
Check out this link to the Morton building site. Morton Buildings, Inc. - Features - Timber Column. An additional advantage is you don't have to use stainless hardware all the way up the pole.

 

[Gizmo2]

I would use soild poles .60 yellow pine and these Post Protector

Laminated posts using 2x6's generally have better treatment through more of the board than do 6x6's. The 2x6 is thinner and the treatment will go completely through. But, the lamination fasteners will give out way before a 6x6 starts to have problems. I have a 32x32 pole barn I put up 22 years ago, it is as solid today as the day I put it up.

 

[HoustonBrama]

VERY good info. I'm gonna go with the 8' solid 6x6's coated with the roof tar and then start my regular 2x non treated boards up from there. I like the felt idea. That'll just be an added barrier. If it all comes falling down in ten years, y'all will be the first to know.

 

[MarkV]

The laminated post were discussed here several years ago and several engineers on the forum did not like the idea. Their problem with the system was that where you join the pressure treated with the untreated section you are creating a hinge point that regardless of how you join the two will be weaker than a solid post against wind load. Pole buildings are not sheathed with ply and tin does not offer any lateral stability to speak of so the poles are taking the majority of any side load.

Can’t say myself but I thought I would pass on what I recall from a previous discussion for consideration.

MarkV