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Raising the roof to fit insulation

When we see them here, they usually do not directly connect the rafters to the ceiling joists, when thrust occurs, the plate(s) can roll and lift.... they end up with some kind of gusset or kicker or bracket to address thrust......I would be slightly concerned about the rafter tails ability to control thrust based on the notch....but if they meet the prescriptive requirements for notching in 802.7.1, should be fine.....
 
DRP,

How wide is the soffit for the truss pictured?

How wide is the bottom cord?

pc1
 
Jeff. I would allow it as built. It is not conventional but it meets the intent imo. The roof sheathing and fascia will provide additional lateral support. I think you have a good design. Any reason you built it this way??? Did you need a new discussion for the board?
 
PC,

It's been a few years and that house was one of those "I designed it myself, you're going to love it" cut up jobs. I believe the outer web members are over the bearing points, the left overhang is 4' I believe the back, right, overhang was 2 or 3' on this truss. I believe the bottom chord is a 2x10, I've had them with 2x10 and 2x12.

Whoops, I think I'm showing a forbidden hook there. We were double checking the SYP strength.
 
DRP, That's what I thought the bearing point is back about 4ft where the web intersection is placed!

pc1
 
So what is the general opinion of this design when the ceiling joist doesn't cantilever over the top plate? I do like this variation, but we never see this around here. It seems this type of design is taking over, especially on the large homes. I've seen as many as 4 plates stacked on top of 2X6 ceiling joists with the rafter attached to those plates. I've been making the builders buy long hurricane clips that attach the rafter and the top plate of the wall like code says. They are all complaining saying nobody else enforces this and they've done it for years.

One builder said yesterday they could build a 4' kneewall on top of the ceiling joists and then attach the rafter to the top of that wall and we would be ok with that. Two plates on top of the ceiling joists is no different ( just a short kneewall). I told him I didn't like either, but I would have to get back with him on his argument.

I don't like the plates stacked and the ceiling joists/rafters not nailed together. The code is too simple for today's stick-frame methods. Someone needs to write an advanced stick-frame chapter just for these situations. These roofs are so cut-up you can't even use a rafter-tie.

I'm about 10 months on the job and am still learning. I asked a national ICC instructor about the 4 plates stacked up on the ceiling joists and he told me to "RUN!". I can't do that, so I need some help.
 
kyhowey said:
I don't like the plates stacked and the ceiling joists/rafters not nailed together. The code is too simple for today's stick-frame methods. Someone needs to write an advanced stick-frame chapter just for these situations. These roofs are so cut-up you can't even use a rafter-tie.
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You got to have a cut-off point somewhere in the codes. The codes are based on accepted engineered practice now. Once you get away from the codes as written then engineering kicks in.
 
Resurrecting another one that had some good discussion. Forget that this is a shed and that the shed will blow over before uplift is an issue on the roof. How can this be done and meet the code prescriptively?
 
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