i will soon be doing my first house on my own and am trying to decide what to use for rafters on a gable roof that is 12′ from plate to ridge and 42′ across.no attic,finished living space vaulted to the collar ties.oh yeah,12/12 pitch.about 24′ rafters.thanks.
RTC
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Do you have a set of plans to tell you what to use or can you design it yourself from where your from?
Also, with a 12' rise to the ridge (with no HAP cut or ridge thickness added) and a 12/12 pitch that means you would have a run of 12' and the rafter length of almost 17' with no overhang. Why 24' rafters? Are you planning on having a big overhang?
sorry i screwed up and so did the architecht.the ridge height is 12' and the run is about 20'.the plans call for 2by6 but i was hoping to go a little thicker(or a lot).
RTC
"sorry i screwed up and so did the architecht.the ridge height is 12' and the run is about 20'.the plans call for 2by6 but i was hoping to go a little thicker(or a lot)".20' span with 24' 2x6 rafters with vaulted ceiling to collar ties. I wouldn't call this guy an Architect. Ask him what he really thinks that he should use. You can use 2x12's for @ 24' but you nave alot more going on there than you think. Does he have a structural ridge in there and where does he have the collar ties and what size are those. The list goes on.Joe Carola
the ridge is spec'd at a 2by8.and the collar ties 2by4.there are 3 small dormers one on one side and two on the front.
"the ridge is spec'd at a 2by8.and the collar ties 2by4.there are 3 small dormers one on one side and two on the front."Now I know your really pulling my leg.Joe Carola
Maybe the attic is filled with helium??
He says he's doing his first house on his own which makes me think that he's a framer building a house for someone with a set of plans that are bullsh!t or he has no set of plans and he's winging it.He has a 40' x 42' building with a 20'rafter run with a 12' ridge height which gives you about a 7/12 pitch with 24' 2x6 rafters that are vaulted as he says to 2x4 collar ties (I call them clipped ceilings) at no height with two dormers one one side and one on the other.His posts make no sense. He's not the one to design this house and neither is no one here. This is why this thread to me is a joke.Joe Carola
i was looking for some advice or at least some backup on what i thought was some bad engineering.yes this is my first house to build on my own.no that does not make me incompetent.i work in all aspects of carpentry and homebuilding. i would rather not call myself a framer because of what most of them look like down here.if it was my roof i would use 2by12 for everything for strength and insulation.no the thread is not a joke.yes i do have plans and yes they were approved by Raymond Stone,State of Texas professional engineer.ya'll have some crappy advice for seasoned veterans of this industry.i'm just learning and would like to absorb all the knowledge possible.
Edited 7/31/2005 1:35 pm ET by rtc
What advice do you want to here. You know you have a set of plans that are that wont work. Everything I mentioned above you have to think about. All you keep asking is about the size of the rafters which is the least of your problems. It a 20' run with a vaulted ceiling to collar ties. You have to have collar ties that are bigger then 2x4's and they have to be at a specific height to work where you don't need a structural ridge.You have two dormers on one side and one dormer on the other side adding more weight to the rafters. You are trying to redesign just the rafters and nothing else and think that's all you need to do. It's not your fault the Architect screwed up and luckily you noticed the size of the rafters but that's all you noticed. So I think your in over your head and I would touch the job KNOWING IT'S WRONG.I would ask the Architect to check over the plans again. They make mistakes and I've caught them before over the years make some pretty bad ones, so I call them up and question them and if they fix it fine if they don't I wont do the job.So you can come on here and you'll get people to respond to you and design your whole house for you but it doesn't mean squat. Your going too change the whole plan on your own. What will you say to the inspector with all your changes?I'm not busting your balls for asking a good question but it's not up to you to redesign a mistake from the architect that he should correct before you even start the job.When I was younger I would see some plans that I new the roof lines wouldn't work and I would actually say to myself this can't be I'm only 22 years old the architect has to be right and I'm wrong but I wasn't wrong and called theses guys up and I was right just like you are but do yourself a favor and call this Architect up and straighten this out.Joe Carola
thank you very much Joe that's exactly what i needed to hear.i have seen many problems with these plans and we're nowhere close to starting.it's just hard to believe that so much could be wrong when it has an official state stamp by a reputable engineer.but it's definently wrong.thanks.
RTC
RTC,
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I have seen very few residential plans In S. Texas drawn by Professional Engineers. Most are drawn by “Residential Home Designers”. Most have a standard disclaimer noted on the plan that the builder and his subs are responsible for all structural aspects of the home, and that they are not responsible for dimensional errors as well. “All dimensions are to be verified on the job and correction made as necessary…….” Etc.
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Maybe it’s different in your location.
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Responsibility for specifying structural framing components is typically passed off to the lumberyard providing the lumber. You should get a detailed take-off from your lumber company. (I insist that all floor systems be engineered.) They may or may not have a structural engineer spec the materials but they will use either current software or span charts to spec the Floor, Beams, Joist, and Rafters to code. If you build enough homes they do not specifically charge for this service. For one timers or first time bids the average material take-off cost about 5 too 7 cents/ft. I’m not in the lumber sales business and I charge 10 cents. If I win the Framing bid I credit the charge back to the customer. I am known to do more accurate take-offs than most lumber companies. I can call the lumberyard for help specing materials/loads if I need it too.
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Call your lumberyard and ask them what they can do for you. If you need a structural engineer to do your take-off find a lumberyard with one on staff.
Good luck, Mr Jalp
Reputable engineer???? If these plans are what he basses hius reputation on, his rep is for crappy work, putting stuff on houses that wouldn't work on a doghouse
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No way an archy designed that. With those specs, it will be sagging and falling down before winter.
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RTC
you may want to look at trussing this house ... I think it would work better if you want to vault that big of space
Tom
Right off the bat, rafters for a 12/12 pitch on a building 42’-0” wide are 32’-0” long and the ridge is 22’-0” high.
Try cracking open your State Building Code—everything you need is in there, and what the building inspector is going to be looking for. There are span tables for the loads in your area, required height/location for collar ties, insulation depth and ridge requirements. You should be familiar with the code anyway—don’t you have a building license?
My advice is to stay away from trying to redesign the house yourself; why are you “trying to decide” what to use when the structural system is already designed and apparently conforms to code?
Rex,In post #3 he says that he has a 20' run with a 12' rise so that gives him a 7/12 pitch with almost 24' rafters with no overhang.Joe Carola
Edited 8/1/2005 12:08 am ET by Framer