pole barn designing 40x64ish

[motownbrowne]

I bought a few pole barn posts last year. They are foundation grade treated 2x6s laminated together for 5, 6, and 7 feet (each board), then they are each notched into a regular 2x6. I found them at a surplus building supply store for $18 each. They're 18' long.

I've never seen them at a Menard's or anything, but someone makes them and maybe they can be found new at a reasonable price. The treating is rated to go in the ground, they are stronger than a 6x6, and have more surface area to absorb the treating.

 

[LD1]

So if I follow you correctly Eddie:

You are saying that you would be okay with 3 treated 2x6's that are full height....or....a solid post. BUT do NOT like the way Morton and others do it with the 5-6-7 or 4-6-8 for treated part in the ground and then the rest of the height out of non treated 2x6's?? Cause just to be clear, its not a bunch of short pieces. Rather each "ply" is only 2 boars with staggering connections between the 3 plys.

 

[LD1]

Also, an update on post spacing and trusses. I had time to put pencil to paper and figure the combos. Looks like if I build, it will be 8' trusses and 2x4's on end, but rather than being on top of the truss, I'll use hangers and place them flush. I have done a lot of reading on this and believe it is the better and stronger way to build vs using a single 60d nail and.putting them on top. And in all honesty, the 60d nails probably cost as much as thenhangers each.

The breakdown is as follows:

1. 4' trusses, posts, and flat purlins with a triple 2x12 over the 12' doors...$4630 material

2. 5' oc trusses and 10' posts only saves 2 posts. Same flat purlins and triple 2x12 over doors....$4440 material

3. 8' oc posts and trusses. 2x4's in hangers for purlins, and same door headers. Added webbing underntruss to get 4' spacing for liner panels. $3200 material. A pretty good savings.

4. 10' oc posts and trusses. I priced this with 2x6 purlins on edge for the 10' span and in hangers as well. I didn't get a quote on 10' trusses, but guessing $180 since 8' is $161. That puts material @, $3907. More than 8' spacing cause of the 2x6's for purlins.

 

[rswyan]

... Which goes a long way toward figuring out how to attach 8' on edge purlins and addind nailers underneath for liner panels.

When Cleary built ours, the crew nailed the purlins on edge with big, honkin' ribbed nails that may have been designed specifically for that purpose ...

I think I ran into the little info/poop sheet for the nails when I was over in the barn looking for something recently.

 

[EddieWalker]

Let me back up a little bit. I'm just agreeing with you that three laminated 2x6's are stronger then a solid 6x6's on the basis that both are more then strong enough to do the job and it doesn't matter which one is actually stronger.

Secondly, I would never use three 2x6's instead of a 6x6 for anything. It's too small of an amount to matter to me and my name when building something. I've never met a client who complained about using the best materials I know of.

My opinion of those mass barn building companies is something very similar to those people that build mobile homes. They have spent a lot of time and effort figuring out how to do it cheaper and faster while giving you a good looking product. I love how efficient and well thought out a brand new mobile home is. I have a huge respect to what they can do for such a low amount of money. And of course, I absolutely hate working on them and finding out where they cut their corners to get it done faster and get by with a lesser material.

I don't think it's so bad that anybody who has one built for them is getting ripped off. I just don't think they are much of a standard to compare to. The bar isn't very high there.

Pole barns are the simplest of buildings to build and engineer. If you follow the basic principles, it will last a hundred years easily. Every time you try something new or unique, you take a chance with the life span of that building.

If you use treated 6x6's you know that they will be sound and strong 50 and probably 100 years from now if they stay dry. Can you say that the glue holding the 2x6's will last that long? What if you don't even use glue, how long will the nails hold the boards together? Have you ever seen a deck built with nails?

I'm not trying to be rude here. I'm sharing what I know and what I feel is the best approach to building. I'll never see the building or have anything to do with it, so it makes no difference what you do.

Eddie

 

[countrybumpkin]

I too am fixing to build or have built a new pole barn style shop and cold storage area. I am moving out of a 30 x 45, and am looking at something along the lines of a 42 x 81 16 foot Walls. I'm then going to put three over head doors in one gable end, then a wall at 30 foot in for a 30 deep, 42 wide shop fully insulated. Be a bit smaller than I have now but I will have the remaining 50 x 42 for parking my motor home and race trailers, tractor, ect. I'm going to get a bid from the guy that built my last one sometime next week on framing the whole building and installing the roof. My last one he built using 6x6 post and trusses on 9 foot centers. I'm really curios as to what he is going to hit me at cost wise.

 

[LD1]

I do sincerely appreciate your input Eddie. Cost is not the only factor at play here. Yes I know both are overkill but again, I am going 14' walls also. Just all of the reading I have done indicates the way Morton and others do the laminated posts is stronger, and better treatment of below grade boards. Being cheaper is just a nice bonus. I am not at all against using 6x6's if they are the better way to go. But up til now, I haven't heard anyone else say they are better. Everything is indicating that the laminated ones are best.

Country bumpkin...looking forward to seeing what your builder comes up with as well.

 

[LD1]

Another question for the group...

Door headers, since they are on the load bearing eave ends.....And more design changes on the fly. But since I am not starting this til spring, it is subject to change again, but would like to get everything planned and drawn out now.

Since I am going 8' OC posts and trusses, that really dont work well for a 12' door opening. So I am considering going 40x72, and a 16' door opening, by just omitting 1 post. But that puts a truss right in the middle of that 16' span, So I need a substantial header.

I have heard several mentions of a pair of 2x12's with plywood in between, or steel in between. But had another thought and it might be stronger than the plywood...And I dont really want that wide of a beam cause I dont want to rule out having an outside wall that is flush like I mentioned.

So here is what I have in mind. Notch the post outside to accept 1 2x12, thus remaining flush. Attach another 2x12 inside the post, but not notched. Rather bolted, as well as a 2 or 3' board running vertical down the post and bolted as well. Then a 2x8 on the top and bottom of them. Basically making a "box" beam.

Also, since I am only going 12' high with the door, and the walls are 14' high, if that isnt sufficient enough, wouldnt adding another 2x12 UNDER the first be stronger than side by side. IE: 2x24 vs 4x12 nominal dimensions?

 

[EddieWalker]

The plywood is what gives the header it's strength. Glue adds to that strength even more. For a 16 foot span, you need two 2x12's and half inch plywood glued to both boards as a bare minimum. I would go with three 2x12's and plywood between each board. this gives you the same width as the 6x6 and the maximum strength.

Glue Lam beams have come down in price and would be even stronger and easier. Cost should be around $150, give or take.

Be sure the beam is resting on solid wood. Either add two jack studs to either side or put it on top of your posts.

Do not do the box idea.

Eddie

 

[LD1]

Do not do the box idea.

Eddie

Any more details on that? Just curious?

I have seen a lot of amish built homes up my way and it seems they always box headers. Windows, doors, garages, etc.

Just thinking along the lines of steel and I-beams and just beas in general. The strength comes from the fibers farthest away from the center, And the more you have the better. Thus my thinking for the 2x8 on top and bottom. Again, thinking steel, a simple 2x4 box tubing is alot stronger than two pieces of flat steel of the same thickness.

And since height is not an issue, why go massively wider when I can add depth? Adding another 2x12 UNDER the first one instead of BESIDE it?

I hope I dont come across as questioning your judgment like you dont know what you are doing. That isnt my intent. I am not a building expert. I am seeking knowledge FROM the experts like yourself. but like anything, I also like reasons, proof, and facts in lieu of "thats just the way we do it", or "dont do that" or "do this". IF a few 2x12s with plywood is what it takes, I'll do it. Just exploring alternatives and looking to gain knowledge.

 

[KennyG]

I would side with Eddie on the built up 2x12s and plywood. Make it the same thickness as the posts. I'm skeptical of wood box beams. Metal box beams work because they are one continuous material. Built up laminated timbers beams work because, even if they aren't glued (which they should be) they all act in the same loading. A wood box beam has different forces acting on the mating pieces and that would worry me. I'm not saying it's not a way to build a strong beam, I'm just saying that if I tried to structurally analyze it I would have to worry a lot about load transfer between the members.

The idea of stacking 2x12s has some merit,but I don't think you need it. 3 2x12s with plywood should be plenty to span 16 feet. If you did stack them, I would want continuous plywood sheets tying them together.

If the Amish are using boxed headers (I haven't seen this) I would guess it's to save material. Headers in house construction are often way over designed.

Anyway, these are thoughts off the top of my head without any detailed evaluation, but when we see "everyone always does it this way" there is often a reason.

 

[bigtiller]

How about making the laminated 2x6 posts on each side if the door a little bigger. 3 Laminated 2x8's would give you room for the forth 2x12 in the header you are talking about ?

 

[LD1]

The idea of stacking 2x12s has some merit,but I don't think you need it. 3 2x12s with plywood should be plenty to span 16 feet. If you did stack them, I would want continuous plywood sheets tying them together.

The idea behind stacking them was to avoid going with a a beam as wide as the posts. I dont want that. The top of the posts are going to be notched for the trusses. Dont want this setting on the beam, only 1 or maybe 2 plys can be notched in and leave room for that.

And since height is of no object here, Adding depth SHOULD do lots more good than width. 2 2x12's in this way I would think would be lots stronger than even 3 side by side + plywood.

As with steel, the most efficient use of material to gain strength is depth. The only time it would make sense to use a shallower but far heavier beam is if space is an issue.

How about making the laminated 2x6 posts on each side if the door a little bigger. 3 Laminated 2x8's would give you room for the forth 2x12 in the header you are talking about ?

Trying to find solutions to build a strong beam and save money. Certainly not wanting to go with a 4th 2x12. Those arent cheap.

 

[KennyG]

I'm having a little trouble envisioning your posts notched for trusses and how that impacts the beam. Will this 16 ft beam be outside the posts, like a wall girt? If so, it would be supported by 2x scabs on the posts. You could laminate inside the posts and would not need additional end support inside the posts. If you want to do the stacked 2x12s I think that should work but I would still put a wide (22-1/2"?) plywood lamination on the inside surface. The other thing to consider is how you will attach the truss at the center of this 16 foot span. With a beam only about 2" wide, the truss will want to twist the beam at this point. Are you going to have an inside girt at the top of the wall to also anchor the truss to? The stacked 2x12s should have plenty of vertical capacity, but there are also horizontal and torsional forces and 16 feet is a considerable span.

 

[LD1]

Here is the box idea I was proposing.

 

[TomSeller]

After five pole barns I can tell you to build bigger than you want..

Any chance of you posting pictures of them? It would be very much appreciated. Or if you did on a previous thread, any reference?

 

[franklin2]

I find all this different design ideas interesting. But do you really have the freedom to make it any way you would like? I built a very small 25x30 garage/shop, and I had to submit plans to the county and they had to be approved. They usually go straight down the middle with conventional building practices. Something like a steel beam spanning a large opening they would shy away from and say "it has to be engineered".

I had a line on a bunch of those tall steel rack legs they use in manufacturing warehouses. They are super strong and very tall also, and I thought I could dig a footer and let it sit above grade, and then take these rack legs and bolt them together all the way around to make the walls. Then put a wooden header around the top, sit the trusses on that, purlins on the sides, metal siding, etc. No way would they approve something weird like that where I live.

Like the laminated post debate. If they had never seen it before over here, it would probably be a resounding NO!

I figured Ohio might be the same way, buy maybe not?

 

[EddieWalker]

I do a lot of remodels and get to see how homes have evolved in building technique over the years. Some things surprise me and I wonder why they did it that way. While I've never seen a hollow box for a header to the scale you are describing, I have seen plenty of headers with lumber at the top and bottoms of them without plywood in between that left a half in void in the middle of the two vertical boards.

In my opinion, and what I know about building, plywood was very expensive and not readily available back then. To get the width of the header the same as the thickness of the studs, they just used a stud at the top and bottom of the header boards to keep them aligned. If the boards are of the proper size, this should work. In most cases it has, but one of the reasons I get hired to fix these things is that it doesn't always work.

Lumber over a span will sag over time. Bigger lumber sags less and it takes longer to happen. You size the lumber according to the span and when there is an additional load on the span, you double or triple up those boards. To make it even stronger, you add plywood between your boards. Plywood or OSB has tremendous sheer strength and it will not sag over time when on it's edge. This is why OSB is being used for I joist. The top and bottoms boards are just there to keep the OSB straight, but don't add much in the way of strength. All that strength in the Plywood or OSB is added to the strength of the lumber used in the header when they are all tightly fastened together.

Glue is stronger then the wood it attaches to. There was a great study that somebody linked to on hear awhile ago that showed that even the cheapest white elmers glue was stronger then all the woods they used in their test. For the cost of glue, it makes no sense not to use it. Especially for something that you are spending a lot of money to build and plan on having the rest of your life.

You can easily install your header on the top of your posts and still have plenty of room for your trusses. Tying them together on the top of the post will give you the maximum amount of strength possible. Then you just frame down from the header for the door opening to the door with cripple studs. Headers can be at any height in the wall.

Eddie

 

[chevy]

2 years ago, we had a 42' X 60' X 14' tall Lester pole barn built by a local builder.
The posts & trusses are spaced 10' on center, It has 2 - 10' X 10' & 2 - 9' X 9' overhead doors.
The posts are full length laminated 2 x 6s.
I built a 19' X 42' loft on one end. The lower ceiling height is 7', the upper ceiling height is 6' 2".
I also added a floor in the truss spaces above the loft floor for storage of light weight objects.
I have not had time to do any interior wiring yet, other then installing the main panels.
The only lights I have at this time are on 2 garage door openers.

 

[ultrarunner]

Nice building and very practical with the loft...