ceiling joist and rafter framing


Electromen
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Is there a way to make the framing look like the attached drawing?  It looks similar to a truss but is stick framed with 2x6's.  The rafter sits directly on top of the ceiling joist and is cut to fit.  The overhang is 1 ft.  The rafter does not touch the wall, so there is no bird's mouth.   I want the bottom edge of the facia to be in line with the bottom edge of the ceiling joist.

post-84-0-84592400-1398453606_thumb.jpg

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Greg,

I realize that I may be sticking my neck out here, but the structural condition you've created can create enormous forces in the rafter/ceiling joist connection. Before you actually build this, I'd recommend you run it by a structural engineer.

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Greg,

I realize that I may be sticking my neck out here, but the structural condition you've created can create enormous forces in the rafter/ceiling joist connection. Before you actually build this, I'd recommend you run it by a structural engineer.

Yes, Richard, I would run the c.j. through to connect with the rafters or provide separate rafter ties. In most standard conditions 5-16d nails are usually ok unless you have something unusual going on there. I think his first post shows that.

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Yes, Richard, I would run the c.j. through to connect with the rafters or provide separate rafter ties. In most standard conditions 5-16d nails are usually ok unless you have something unusual going on there. I think his first post shows that.

 

Maybe I'm not getting something here. What is being shown is a cantilevered overhang.  The roof load is at the end of the ceiling joist creating a bending moment on the ceiling joist at the load bearing wall. It seems like this would not be a good idea for anything but very short roof spans.  Seems like a better approach would be a support structure the places the direct load of the roof onto the load bearing wall instead of using a cantilever... Am I making any sense, or just blowing into the wind?

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Maybe I'm not getting something here. What is being shown is a cantilevered overhang.  The roof load is at the end of the ceiling joist creating a bending moment on the ceiling joist at the load bearing wall. It seems like this would not be a good idea for anything but very short roof spans.  Seems like a better approach would be a support structure the places the direct load of the roof onto the load bearing wall instead of using a cantilever... Am I making any sense, or just blowing into the wind?

What you are saying makes a lot of sense.  Now I will get a bit technical.  Forgive me Bill,  I am bored,  waiting for Lynn to get home withs my Dinner Salad,  yep,  more rabbit food.

 

I am sure you know this but putting a load on a cantilever actually will help out that center span.  So,  with the load at the ends of the cantilever,  we have actually decreased the moment at the middle of the ceiling joist.  I know I know,  not worth the trouble to figure out the max's and min's  (might have to throw in a bit of calculus her).  I think he is almost creating a job built truss.  Put a vertical member between the rafter and ceiling joist directly above load bearing wall,  nail together with a ply gusset,   and we have a cantilevered truss,  who would of thunk it?

 

Hey,   when is X-7 coming out?  Oooh,  I wonder what little secrets they are working on this time.  Hey CA,  give us a taste on what might be in the offing.

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Hey,   when is X-7 coming out?  Oooh,  I wonder what little secrets they are working on this time.  Hey CA,  give us a taste on what might be in the offing.

Not before next February - but probably closer to 14 more months if history is any guide.

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I am sure you know this but putting a load on a cantilever actually will help out that center span.  So,  with the load at the ends of the cantilever,  we have actually decreased the moment at the middle of the ceiling joist.  I know I know,  not worth the trouble to figure out the max's and min's  (might have to throw in a bit of calculus her).  I think he is almost creating a job built truss.  Put a vertical member between the rafter and ceiling joist directly above load bearing wall,  nail together with a ply gusset,   and we have a cantilevered truss,  who would of thunk it?

I failed to show that detail in my OP, yes that's exactly how the stick framing is completed.  It's inspected by local authorities and approved by them.

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