Building A frames for barn roofs

An interesting book, if you can find it online, is the Midwest Plan Service's "Designs for Glued Trusses." Here's an example truss that shows what you want to do is possible.

Looking at a 24' truss with a 5/12 slope and 4' truss spacing, low dead load, lowest snow load they have:

2 web (3 vertical 2x4's and diaganal 2x4's from the top center down to the bottom of the outer 2x4's)

top cord doug-fir: 2x4 Hemlock:2x6
bottom cord: 2x4
end of truss gussets: 3/8" plywood, 4"x10:
top center gusset: 3/8" plywood, 10x12"
bottom of first vertical 2x4 gusset: 8"x8"
Crane load with hemlock: 1459lbs

Even with medium dead load, high snow load, and hemlock, its still only
2x6, 2x6 cords
2x4 bracing
3/8" plywood 4x18, 10x12, 8x8 gussets

This is glue and nail construction. Much better than the bolts.

As others have said, the 2x6 is stronger on edge than the 4x4. Calculated value is 165% stronger.

I'm not sure of what you are designing. It sounds like 10' side walls, then the A-frame on top of that. Are you putting hay on the bottom of the A-frame? Making it a second floor? If so, then thats a different matter, and the floor has to be designed for the weight.

Michael

Big A. Nope, no second floor. WE have no slow load, but perhaps a heavy roof wqould be a good thing. Keep it on the roof when Mother Nature sings the Okla Anthem. OOOOOOOOOOOOOOOOOOOOOklahoma, when the wind come blowing down the plains. LOL. I suppose its also WINDY IN KANS. We never noticed the wind when I was home in NE Kans. Course, had hielacious hills to curb it abit, being 2 miles from the MO River.

I like that Greenhouse design very well! My question is what would be "appropriate" roofing materials? We will sheath the structure with plywood and shingles? Or how about a Tin Roof?

and I guess I would pour a floating slab as the floor. I also see windows as being a challenge.

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Well I can`t win the bet for stackin back from a fork, but maybe the hay convayor. Our barn holds 8000 bales, and it has been full more than it had been empty. We had a very good system for filling the barn, we have a 60 foot hay convayor running the full lengh of our barn, and another running up to it outside. We have a kickoff on the upper convayor so we can dump them off anyplace in the mow. We can fill the mow clear to the ridge less where the convayor sits. It is a realy cool setup and works well. Thanks Marc.

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SV What u describe is a pretty old setup also. Dont know if they still make it or not. But they were mounted at the top on the hay rail. i dont know how u moved the kicker forward or backward tho. never actually seen one. I would think that one bale, dropping from a high distance, would bounce quiet a bit. Also, if your mind was in Ark, u might get hit by another following bale, and the raised dust would be continious. With grandpas barn, The dust did raise, but it settled quickly, and the barn would be quite clear of it before another load came up, it was NOT a really fast system. But it was easy to do. Most of the barns I worked in were round 40 X 40, 40 X 50,. I had an aunt who inhearted a farm from a doctor who she had taken care off. Her hay barn was round 60 X 100, 1 story. She also had the old style barn that was 2 story, that had the horse and cow stalls. It was around 32 X 36. We never put hay in it, Id never been in the loft. If I had, I forgot it. I think they kept straw in there, as I never saw inny in the hay barn.

Just thinkin about it. About a mile from the Mo River, by St Joe, outside Elwood Kans. I remember a big, high sided barn that had 2 hay tracks comeing out the same side. And, Im sure Ive seen a barn that had a hay track come out both ends of a barn

We were thinking metal, but you could use regular asphalt shingles too. Just make sure you have some sort of over hang from the high part of the roof to the second part. And seal it really well there too so the wind can't blow rain up in there.
As far as the windows go, you can build the walls to any height you need. We built ours at 5'. So you could easily put a window in their. Also, windows can go on the ends very easily. If you wanted to get really fancy, you could build dormers even.

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Well Bill, you can get thumped in the back of the head if ya ain`t payin attention with our set up. The dust ain`t bad, and I move the kickoff manualy. I only move it once or twice as if it`s off you fill the back, then I fill the middle, and lastly the front. I was 15 years old when dad put the setup in the barn, sure beat the elevator. Thanks Marc

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The only thing I have ever heard about using plywood gussets that was weak were the nails and Dave's suggestion takes care of that. Pricey to use SS but if you think there will be condensation then the little added cost might be worth it. Air nails are coated though. Nails have a little more flex than screws and work better in framing structural pieces. On a glued joint I'm not sure I'd worry about using screws though.

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High winds means good wind bracing. 45deg braces at each post up to the bottom cord of the truss. Each corner gets 2 braces, one for each wall, from the top of the corner down to the next post bottom. The roof gets a diaganel in each corner as well. This book from Menadrs is fairly decent in showing how to build a post frame building.

The 165% I mentioned was supposed to be 165% of the 4x4's strength (65% stronger), not 165% or 2.65 times stronger.

I really like the polyurethane glues for water proof construction. If the joints are tight, I like the spread-ability of the woodworking glue like Gorilla Glue. You get almost 100% coverage of the glue joint. For less well fitting parts I use the PL Urethane construction adhesive. The glue is VERY strong, waterproof, and allows a reasonable amount of time to get everything set up before it hardens.

I think you mentioned a horizontal tie at every other truss. I would suggest using the 2x6's and go with a 4' spacing. Put a tie on the base of every truss. It makes for a stronger building. If you want a larger opening (6', if I read correctly) you could upsize the wood, and just have a 6' spacing. 2x4's on edge for purlings (roof pieces) are fine, and you cover it with metal.

The above is for an A frame with the horizontal member at the base of the A. Are you talking about a truss in the shape of "A"? The horizontal member a few feet down from the peak, and that's where you would mount your rack? If so, then it brings up a few more points like whats the span rating of the horizontal member, how long is it, etc.? What kind of pitch were yo thinking of for the roof?

Michael

Bostich has Nails for hurricane and earthquake prone areas. They call them Hurriquake Nails. They have galvanized. I've used them, once they are in they don't come out! See the link below.

http://www.bostitch.com/xhtml/intera...uake_show.html

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. Art, Ive gotta go across at the bottom makeing the A instead of the reversed V around every 10ft, to give the hay enough space to dump through them from the hay trolley. The guy at Lowes today suggest a doz nailes scattered at each joint, and useing Liquid Nails for the seal.

many roof plans,
http://www.ag.ndsu.nodak.edu/abeng/c...ctionplans.htm

many many plans
http://www.ag.ndsu.nodak.edu/abeng/plans/