roof rafters - no ceiling
roof rafters - no ceiling
(OP)
I'm working on a framing plan for a customer - the house has a very large 12/12 pitch roof and much of the 2nd floor is located inside of it. The living room of the house, on the plans, shows a vault from the exterior walls going flat at the same height as the 2nd floor ceiling. The longest rafter span (to a king rafter) is ~21'. There is also no way to support the ridge as it is over the living room.
End result is I can't use an i-joist rafter because there is no where to support a structural ridge, conventional framing doesn't even come close to working b/c the lack of ceiling makes the rafters way out of span. I thought about designing the top plate as a beam but can't get it connected at the ends.
Any ideas?
End result is I can't use an i-joist rafter because there is no where to support a structural ridge, conventional framing doesn't even come close to working b/c the lack of ceiling makes the rafters way out of span. I thought about designing the top plate as a beam but can't get it connected at the ends.
Any ideas?






RE: roof rafters - no ceiling
RE: roof rafters - no ceiling
RE: roof rafters - no ceiling
Mike McCann
MMC Engineering
RE: roof rafters - no ceiling
I don't think that the 2nd floor extends over the living room.
RE: roof rafters - no ceiling
The OP said:
"the house has a very large 12/12 pitch roof and much of the 2nd floor is located inside of it. The living room of the house, on the plans, shows a vault from the exterior walls going flat at the same height as the 2nd floor ceiling."
I still see a collar tie situation here, even with a flat vaulted ceiling in the living room, the ceiling of which is the second floor.
Mike McCann
MMC Engineering
RE: roof rafters - no ceiling
Mike McCann
MMC Engineering
RE: roof rafters - no ceiling
The collar tie is the ceiling joist for the 2nd floor, the floor joist will be lower and never come in contact with the rafter.
Scissor trusses aren't an option...customer does not want to use them as they'd have to be 2 pieces + lots of overframing as well.
RE: roof rafters - no ceiling
RE: roof rafters - no ceiling
I have done this several times in cottage style houses that I have framed.
I'm still not clear as to what you are describing.
I also cannot think of why you cannot use a ridge beam. I have installed ridge beams (LVL 3 or 4 plies, or glulams) that spanned 48'-50' supported by wall framing in the gable ends of the house.
RE: roof rafters - no ceiling
BA
RE: roof rafters - no ceiling
Solution might be to run a horizontal beam along the wall to carry the horizontal loads out to the sidewalls.
Timing has a lot to do with the outcome of a rain dance.
RE: roof rafters - no ceiling
There is no such thing as a "roof rafter" - that's saying the same thing twice, double dipping, repetition for emphnasis, bad termonology, etc. It's a term devised and misused by Architects, and, consequently, misused even by some of us structurally. Don't do it. It also implies that there is such a ridiculous thing as a "floor rafter".
A "rafter" is the proper terminology, and refers to sloping members framing between ridge beams, hips, valley members, and wall top plates.
A "roof joist" would refer to a flat or tapered member framing between the same.
Educate these Architects! Don't let them mislead you! This is a conspiracy!
Mike McCann
MMC Engineering
RE: roof rafters - no ceiling
BA
RE: roof rafters - no ceiling
Of course there is such a thing as a 'roof rafter'. You might not like it, it may be bad terminology, the 'roof' word may be redundant, but that doesn't mean that it doesn't exist.
RE: roof rafters - no ceiling
BA
RE: roof rafters - no ceiling
The term may be accepted by some, but that does not mean that it is not a morph of the original accepted nomenclature. Reinventing the rule to your own scruples does not change the rule.
Look at the Architectural Graphics Standards, or the Douglas Fir Use Book.
Mike McCann
MMC Engineering
RE: roof rafters - no ceiling
So, what other kind of rafter is there? The use of "roof rafter implies that there is.
It was tough enough when I came to the States and had to convert from "siding rails" to "girts", I hope they are not now called "wall girts".
Michael.
Timing has a lot to do with the outcome of a rain dance.
RE: roof rafters - no ceiling
http://www.buildeazy.com/glossary/
Mike McCann
MMC Engineering
RE: roof rafters - no ceiling
Seeing the term "There is no such thing as a...." tends to fire me up. :)
BTW Michael, I'm sure you meant 'side rails', siding is a US term.
RE: roof rafters - no ceiling
I've never seen someone get so pissy about a little misnomer.
Do you also get pissed when someone says "footer" instead of "footing"?
RE: roof rafters - no ceiling
My point was not made in anger. If you construed that, you're wrong. I am a stickler though on using proper English as well as proper technical terminology for what I perceive is my profession. It was merely meant to educate. Take it as you will. No worries, and no offense intended.
Mike McCann
MMC Engineering
RE: roof rafters - no ceiling
Apsix, I must have been stuck in Mid-Atlantic, I intended to write, "Sheeting Rails".
I thought we were just passing time, waiting for a sketch of the problem, especially with all of this ambiguous terminology floating around.
Michael.
Timing has a lot to do with the outcome of a rain dance.
RE: roof rafters - no ceiling
Personally I would not call a roof joist on a flat roof a rafter. I would call it a joist, but if it can be called a rafter, then maybe floor joists can be called floor rafters.
Just kidding! I really don't find the term "roof rafter" to be all than offensive.
BA
RE: roof rafters - no ceiling
I wound up not doing anything. The contractor is in an area where engineers aren't required & he "can make it work." Just thought an engineer could help him. I'm interested to see if I hear back from him.
Thanks for all the replies.
RE: roof rafters - no ceiling
BA
RE: roof rafters - no ceiling
And, post a sketch.