Pole Barn Design-Over Building?

[bitternut]

I suggest that if you want a decent barn that you do not use rough cut hemlock for the framework construction. There are a couple reasons why I say this. First and foremost is that I am familiar with the Amish in your area and as far as I know their hemlock is not graded. In other words it may have different moisture content, large knots, and quite often shake. This results in low strength lumber with varying sizes. Rough cut hemlock certainly should not be used for trusses. I had the local Amish build my barn with such lumber and I have regretted it ever since. I was not unhappy with their work, just the results you get with rough cut hemlock. Also do not use any posts that are less than .60 treated, be they solid posts or laminated. That rough cut hemlock can vary in size a considerable amount from one board to another. I used solid 6 x 6 .60 treated posts with hemlock 2 x's for the framework. The outside is board and batten 1 x 10 white pine with a gambrel roof.

If you want a good building do your self a favor and go take a look at a couple of those barns with a "M" on the front of them. Take a digital camera with you. Kenny has also given you some good advise. Good luck in your project.

 

[Scotty370]

Bitternut-Points well taken! The Sawer that I've dealt with before turns out accurately sized boards, but your right about moisture content. It's all green wood and fresh cut. No drying, stickering, etc. Your taking it off the the 'blade'!! Yes, I'm familiar with Morten buildings! KennyD's got me turned around, to the manufactured trusses, and fully PT'ed subsurface wood products. I've Got an RFP out to a local lumberyard to get me a price on 30' "W" (fink) trusses w/4/12 pitch. Should get that tommorrow. Bottom line is that I want to design a plan that, will work, is what I want, and do it in the most cost effective manner. As Ken suggested, I may just go to the Amish, in the end, and say: "Quote me this building". But at least I've got plans to show them, or anyone! Scotty "Still Drawing" 370!!!

 

[kennyd]

Bitternut-Points well taken! The Sawer that I've dealt with before turns out accurately sized boards, but your right about moisture content. It's all green wood and fresh cut. No drying, stickering, etc. Your taking it off the the 'blade'!! Yes, I'm familiar with Morten buildings! KennyD's got me turned around, to the manufactured trusses, and fully PT'ed subsurface wood products. I've Got an RFP out to a local lumberyard to get me a price on 30' "W" (fink) trusses w/4/12 pitch. Should get that tommorrow. Bottom line is that I want to design a plan that, will work, is what I want, and do it in the most cost effective manner. As Ken suggested, I may just got to the Amish, in the end, and say: "Quote me this building". But at least I've got plans to show them, or anyone! Scotty "Still Drawing" 370!!!

You have a good handle on it now... I would be vary cautious about green lumber also...air dried a few years OK, Kiln dried even more OK but green-not for me.

I did the same as you-then got the price I told you before and was slapped in the face with the realization that I could not do it myself cheaper than they could, I hope you are as lucky.

 

[buckeyefarmer]

Check out these web pages to get an idea of the design.

Kit Includes :: APM Pole Building & Garage KIts

These guys will do the design for you if you buy their material (kit barn). These guys may not be in your area, but other lumber yards also do this.

 

[Scotty370]

Thanks Buck! More good info!!! Bookedmarked for sure! ~Scotty

 

[dcyrilc]

So the pulins on the roof don't sag, they are just 2x4's laying down. the 2x12 beams hold up the trusses between the post's.

I've also seen and wondered about that. Now I understand. Standard around here is trusses either side of all center posts at 12ft OC for post spacing, but we always have 2x6 perlins on edge also. 2x4's flat would make a huge difference to the structural strength of the roof.

 

[schmism]

id check with your local lumber yard on what AG trusses they have on file that they can order.

i can tell you that standard AG trusses will come in 4,6,8,10' OC. standard AG loading should be something like 20-5-1, although local snow loads will vary the top chord live load. Top chord perlin spaceing is normally 2' OC but can be varied if factored into the truss design. but over 4' OC is uncommon due to support issues with the tin.

the nice thing about ordering a pole barn package from a truss company is they can plate treated material on the bottom 5' of the posts and then transition to standard material to save cost. sidewall height and OC post spaceing will play a role on size of posts (3ply 2x6, 4ply 2x6, 3ply 2x8 etc)

 

[rambler]

There is a little engineering to building a good shed. Height of the walls is important, I didn't notice you ever mentioning that..... No one can really tell you what size poles to create without knowing how tall the sidewalls are - wind load gets worse on taller buildings.

Don't use green wood, or untreated wood, in the ground. That was aready covered, but reading this thread, I just had to say it also! 9 times out of 10, that would be a foolish mistake that would wreck your day within 10 years.

Often the best bang for the buck is to have a truss only on top of each set of poles. Then that top board around the walls doesn't have to be so big as it doesn't hold any weight. The trusses need to be bigger, but you only need 1/2 as many. Put the purlins on edge & possibly closer together - but it still pencils out cheaper this way than trying to do 6 foot poles & 3 foot trusses (or 8 & 4) - every other truss will want to sag, so you need a terrible strong doubled top girt.

If you engineer it all out proper, the best bang for the buck is a bigger truss, less of them, and perlins on edge to hold the tin.

If you just are guessing and overbuilding here & there and underbuilding there & here to hope it all holds together, well then who knows what is cheaper or too cheap?

I do hope the package deal comes out cheaper for you - it should. But the planning & figuring is sure fun, so no harm in that.

--->Paul

 

[Scotty370]

Latest progress:

 

[GE222]

Have you considered a floating slab with the building bolted on top?

No chance of wood touching the ground and rotting away. It is also easier to have the top of the floor higher than the surrounding grade for drainage away from the building.

My building is 42' x 48' on a floating slab in southern Wisconsin. The posts and trusses are 8' on center. It is a Lester building.

I agree with the other comments. It isn't worth the effort to build your own trusses, not to mention trying to keep them all consistent.

I didn't notice on your design, but for ease of access and ventilation having an overhead door at both ends is really great. Also having 2' eves as well.