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Is it possible to frame a hip roof without ceiling joists? I know you can do it with a gable having a structural ridge supported on each end, but what about a hip. With no posts under the hip or ridge would it want to kick out and the ridge go down?

It seems to me that the hips would put a lot of thrust on the corners wanting to push outwards unless you had some kind of super strong bracket to bolt the hips into or something.

I was wondering about framing a carport with a hip roof and no ceiling joists. So there is nothing except a beam all the way around on some 6x6's. Has anyone done one without ceiling joists? What do you have to do different to make it work that way?
 

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diplomat
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The sheathing & top plates hold the corners together. The thrust to worry about is at the tails of the common rafters. If you build a square hip roof, you can do it without ceiling joists.

Someone with more knowledge please correct me if I'm wrong.
 

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diplomat
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How big? You can get away with a lot if overbuilt the right way. A solid beam all the way around might be plenty to support the thrust on a smaller building. The steeper the pitch, the less the thrust.
 

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Sure, I can do that...
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Not saying it can't be done, but how long did you plan on defying gravity?

I would think that other than ceiling joists, perhaps a set of timber trusses complete with a tie beam at each hip intersection might be required.
Or maybe buttress the walls with small sheds attached to the sides. The sheds could be shear walled to hold the original building in its original shape.

Two rules about gravity that I have discovered.
1. It can't be tricked.
2. It never sleeps.
 

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I have framed a cathedral hip roof. There was no ridge because the top of the roof was flat, 6' wide. The hips and perimiter of the flat portion were framed with LVL and steel flitch plates bolted together. At the intersections the plates were all welded.
We built the steel and LVL frame on the deck then broke it down, staged and assembled in place by hand.
You will be working closely with an engineer. Hardly seems worth all the effort for a car port roof.
 

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I framed a vaulted hip kitchen bump out addition.. like 16 wide x14 deep off a two story...

My engineer spec'd a 2x12 top plate (yes..on the flat) on the perimeter walls, steel strapped at the corners. No collar ties, and the ridge was semi-bearing, as it was fixed at house wall

I used it to frame a little tray soffit and they dropped some uplights in it
 

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Is it possible to frame a hip roof without ceiling joists? I know you can do it with a gable having a structural ridge supported on each end, but what about a hip. With no posts under the hip or ridge would it want to kick out and the ridge go down?

It seems to me that the hips would put a lot of thrust on the corners wanting to push outwards unless you had some kind of super strong bracket to bolt the hips into or something.

I was wondering about framing a carport with a hip roof and no ceiling joists. So there is nothing except a beam all the way around on some 6x6's. Has anyone done one without ceiling joists? What do you have to do different to make it work that way?
I built a timber-ish roof with structural hips once. Had a fabricated metal piece at the top that all the hip members were inserted into and through bolted. Then smaller timber rafters and 2x8 T&G car decking for roof sheathing. I don't think Simpson made the peak metal. It was stainless steel and probably custom fabbed to some engineered spec.
 

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Okay, I'm going to jump in here for some input, and hope someone is still interested in this thread. We have an old concrete block "ex-"garage- exterior dimensions 12x30, with a hip roof, 6/12 slope, with 18' ridge. There are currently ceiling joists (We removed ceiling), and I would like to move them up a bit as rafter ties, and preferably omit every other one. On one end of the building, 8' of ceiling joists will stay in place, with decking on top for storage. We live in Central Oregon where we get snow, so need to consider snow load. Am I crazy? Some photos below. View attachment 506446 View attachment 506447 View attachment 506448
 
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