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Scissor truss intersection

Scissor truss intersection

Scissor truss intersection

(OP)
I'm in the process of designing my own barn with scissor trusses. The barn has a floorplan like a + sign, which means two wings with a 90 degrees intersection in the center. Both barn wings should be done with scissor trusses and are 36' respective 40' wide. Here my questions now: Can scissor trusses intersect in a way, that the ceiling goes up in the center to the top ridge ? Can there be a cupola in the center ?

RE: Scissor truss intersection

Yes.

RE: Scissor truss intersection

The trusses at the inside square should be girder trusses supporting stick framing of the center section.

Mike McCann, PE, SE (WA)


RE: Scissor truss intersection

(OP)
Thanks Mike for the helpful answer.

RE: Scissor truss intersection

you have to look at the 'cross' part a little more carefully and maybe have a bulkhead or something for the girder truss... they cannot be 'scissor truss shaped' and the depth of the heels will be different for each truss in this area.

Dik

RE: Scissor truss intersection

I've designed trusses in situations like that. If you have some depth to work with and a creative truss designer it can be done. But don't expect it to be cheap.

RE: Scissor truss intersection

As a former truss designer, I couldn't resist taking a swing at this. Please see the attached sketch and note the following:

1) You'll need a heel depth and roof / ceiling pitches that make the central girder possible. Talk to a truss fabricator.
2) This solution assumes that you don't mind having some trusses below your cupola.
3) I expect that this would be a very economical solution relative to hand framing. Of course, I have an obvious bias.

KootK

The greatest trick that bond stress ever pulled was convincing the world it didn't exist.

RE: Scissor truss intersection

(OP)
Thank you all guys.
RontheRedneck: I think we have some depth to work with. KootK did not already take the challenge.
KootK: Thanks for your draft and the time you invested into this. However,
why the trusses have to be under the cupol ? The square cupola structure could sit like a keystone on top of the trusses in my opinion. Any reason why this would not work ?
Regards and thsnks for all your help.

RE: Scissor truss intersection

I'm not sure what you're proposing DB. I proposed trusses beneath the cupola; you're suggesting a cupola above the trusses. Are we not talking about the same thing? It might be your turn to draw a sketch.

The greatest trick that bond stress ever pulled was convincing the world it didn't exist.

RE: Scissor truss intersection

(OP)
Hi Kootk,
I'm just travelling and can't scan anything, but what I imagine is 4 pieces of your part "C" (right bottom of your drawing), instead of one part "B" and 2 parts "C" connected to it in the center. Can't 4 "C"s be connected to the corners of a square cupola Cuboid in the center? Such a cuboid would also provide the depth to work with for the parts you marked "D".
Regards,
DB

RE: Scissor truss intersection

I was afraid that was where you were going DB. In short: no, you can't do what you're proposing.

Maybe with a cupola framed in steel with some big money connections you could swing it. I don't see you ponying up that kind of dough for a barn though.

The greatest trick that bond stress ever pulled was convincing the world it didn't exist.

RE: Scissor truss intersection

If I were designing it I wouldn't run diagonal girders like KootK did. I'd use scissor girders on the left and right sides. The trusses running left to right would have steps built into the top and bottom chords in order to form the slopes.

KootK, I'm not saying your way of doing it is wrong. It's just not the way I would do it.

RE: Scissor truss intersection

No sweat Ron. Diversity of opinion is the name of the game here. If your scheme is workable, it's probably much better suited to the OP's cupola plans.

The greatest trick that bond stress ever pulled was convincing the world it didn't exist.

RE: Scissor truss intersection

(OP)
Thanks for all your contributions.
Has anybody an idea which engineer or truss company in Florida (Sarasota/Bradenton area) could do this ?

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