With houses growing in size, if you built story and half houses with 9/12 pitch or greater, it seems to me you need 22, 24, 26 foot rafters. How easy is it to source such 2×10’s or 2×12’s? Are they typcially 2x12s? Are they straight?
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Between twenty feet and sixty feet, I call them TJIs and they are straighrter than you can imagine
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If you use TJI and you want open rafter tails? ? ? ? ? ? Pain in the AZ ????
Piff,
What has been your experience using I-joists for rafters? I tried to use them for the last house we framed, but they told us they couldn't. I'm going to try a different company next time as I think it can be done. We ended up using trusses and it was miserable.
I don't have trusses available for most jobs because of the ferry between here and there. I hate to use I-joists for complicated jobs because of the extra dildos you have to use to deal with things, but for a large straight plane, they are ideal, which is what I heaar being asked in this thread.
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
I've seen my share of 26' and I've even seen some 28' dimensional pieces.
In fact, on the north east side (of Detroit) it's quite common for the builders to still stick frame. They are sending packages of 2x6 24' and 26's every day! They beef them up with "snow braces". I think the entire idea is absurd, and I won't deal with builders that won't supply trusses. Those particular group of builders think they are saving money because they can get the roof package for 500 or 1000 dollars less than trusses and they won't pay the carpenters more than the cheapest sq ft price that they can obtain....which is way cheaper than i could work WITH trusses!
Stupid carpenters....]
blue
Warning! Be cautious when taking any framing advice from me. Although I have a lifetime of framing experience, all of it is considered bottom of the barrel by Gabe. I am not to be counted amongst the worst of the worst. If you want real framing information...don't listen to me..just ask Gabe!
I don't know about using 2x6s but some times I don't think you can use trusses. If you really want a story and a half with the slanted ceilings and some areas open to the downstairs, you can't use trusses.
Jack, anything you can do with stick frames, the truss guys can do with trusses.
Sometimes the prices don't make it feasible though.
You might be thinking of a different design than I'm thinking though.
blueWarning! Be cautious when taking any framing advice from me. Although I have a lifetime of framing experience, all of it is considered bottom of the barrel by Gabe. I am not to be counted amongst the worst of the worst. If you want real framing information...don't listen to me..just ask Gabe!
"If you really want a story and a half with the slanted ceilings and some areas open to the downstairs, you can't use trusses."
I do trusses on houses like that about once a week.
They're definitely a challenge, though. And sometimes I'd like to tell the framers to stick it. (Double meaning intended)
(-:
I was going 70 miles an hour and got stopped by a cop who said, "Do you know the speed limit is 55 miles per hour?" "Yes, officer, but I wasn't going to be out that long..."
And sometimes I'd like to tell the framers to stick it. (Double meaning intended)
(-:
How often do they get your meaning? :-) That's pretty funny, I wonder if my boss has been using the same double meaning all this time and we've never "appreciated" the joke. ehehehehe
Boss,
I don't understand. How do you truss a cathedral ceiling if you don't have the room for a scissor truss? You want the 9 in 12 or 12 in 12 pitch to show inside?
I am thinking of cases where you have open lofts. Scissors would just be too low. And again I like the high pitch inside . I think a 4 in 12 pitched interior looks stupid. Less is even worse.
I think Boss does a three pitch difference if you want a 9/12 pitch inside the outside pitch will be 12/12 or if you want a 12/12 inside the outside will be 15/12. I'm pretty sure he wrote that somewhere maybe I'm wrong he'll let you know.Joe Carola
Edited 12/11/2004 3:18 pm ET by Framer
Or he might use a truss with paralell top and bottom chords. That would be sweet for added insulation depth.
I don't think I understand. Maybe you meen something like this. Do they even make something like this?Joe Carola
Framer, neat idea. Maybe they do build them. I have never seen one. But then again, why not just STICK IT.
Trusses like you drew are possible in short spans - Maybe up to 24' or so, depending on the depth, pitches, and loading. But you pretty quickly get into problems with horizontal deflection as the spans get longer.
Practice safe eating - always use condiments.
What about using floor trusses for rafter?
With a seat cut on the bottom(sitting on top of deck w/appropriate sized plate)
Using those trimmable floor trusses w/plywood on the last foot of each end
Couldn't you cut them like a rafter? I'd like to use the 9-1/2" size.
Would it be cost effective?(material costs, my labor is free)
I'm thinking on this for my 1 1/2 story 12/12 pitch house I'd like to build
one day. The span will be 28' w/ 2 narrow(4') dog houses(dormers)
on front.
For a floor I have another question regarding floor trusses,
I've never used floor trusses before, so don't know much about them.
With that same 28', would it be better to use 28' trusses which it will have
a center support wall (at 14') or to use 2-14' to span the 28'?
I like the idea about floor trusses for the open web to run mechanicals
Butch, I've framed roofs that used open web trusses that looked like floor trusses. Boss said that they can make them up to about 24'. In those settings, you need a load carrying beam instead of a non loadbearing ridge.
I suppose all these factors add up and make them cost prohibitive.
blueWarning! Be cautious when taking any framing advice from me. Although I have a lifetime of framing experience, all of it is considered bottom of the barrel by Gabe. I am not to be counted amongst the worst of the worst. If you want real framing information...don't listen to me..just ask Gabe!
Blue thanks for the reply
I don't have my rafter book in front of me but with a 28' deep building
I should only need approx.21' floor trusses, correct?
Why would I need a ridge beam? Wouldn't they self support at the peak
like a regluar rafter?
Butch, thats good question. I don't have any engineering background and can only relate what I've done, which has been approved by engineers.
Boss, or other knowledgeable sources will have to explain the loading properties of trusses...but your supposition seems to be correct...I've just never seen it done.
blue
blueWarning! Be cautious when taking any framing advice from me. Although I have a lifetime of framing experience, all of it is considered bottom of the barrel by Gabe. I am not to be counted amongst the worst of the worst. If you want real framing information...don't listen to me..just ask Gabe!
"What about using floor trusses for rafter?"
I've only done it a couple of times. They're a lot more expensive per foot than I-joists, so they aren't used too often.
As has been pointed out, you have to have a ridge beam. It may be possible to get engineering to do short spans without a ridge beam. But I think you'd have a hard time getting it by an engineer.
"With that same 28', would it be better to use 28' trusses which it will have
a center support wall (at 14') or to use 2-14' to span the 28'?"
I'd use a single 28' truss designed for center bearing. That way your truss is continuous, and it makes your plywood go down easier.
In the house I live in, I used 28' clear span trusses 24" deep on half the basement. That way ALL the mechanicals are in the floor system - HVAC and all. And there are no posts in the basement on that side.
Shotgun wedding: A case of wife or death.
Boss, thanks for your reply
Maybe you can explain it to me, Why would you need a structural ridge
with floor trusses as rafters, like I suggested to blue, wouldn't
they be bearing against each other, just like regular rafters with a
non structrual ridge
Also thanks for the info on "my" floor trusses
Now what depth would you use, I would be concerned about the height
so was thinking maybe a 9-1/2" deep truss maybe 19.02" oc
with only 13'-4" clear span. What kinda of floor would I achieve
(dead/live load)
"Why would you need a structural ridge with floor trusses as rafters..."
Without a ridge beam, the whole floor truss is in compression. And you'd have horizontal reactions to deal with at the walls.
If you have the ridge beam the truss would act more like a normal truss.
Marriage is the mourning after the knot before.
And you'd have horizontal reactions to deal with at the walls
Even when trusses would be on top of the deck(decking),
With a rafter plate equal to the width of the seat cut sitting on deck?
I don't really follow your question. With a ridge board, you get a horizontal reaction REGARDLESS of the framing type. With a ridge beam, there's no horizontal deflection.
I intend to live forever.
So far, so good.
Well, I wasn't thinking of that, Joe, but that certainly is a great example of why I love the give and take of this forum so much, one thought leading to another.
Anyway, what I meant was a flat truss that would be 1/2 of what you drew there. You'd use it like a rafter in a stick framed roof. I can see several advantages over dimensional lumber, especially for real long spans.
If I can butt in for a second.... Jim, did you happen to get my reply email regarding the shed roof?
We use finger-jointed rafters,pretty decent stuff. Ever see TJI joists,finger-jointed.
I didn't do it....the buck does NOT stop here.
I think the ingerjoints in an I-joist rafter is different. The stresses are pretty well controled in a tension and compression nature by the web. I would suspect that the fingerjoints do well there. But I would be very frightened of a finger jointed 1x10. Maybe and probably wrong, but a preference.
When you look at the ads for building supplies and they advertise I-joist for floors, are they the same beast for a rafter? Or are there rafter I-joist and floor I-joists?
"When you look at the ads for building supplies and they advertise I-joist for floors, are they the same beast for a rafter?"
Yup - Same thing.
Each manufacturer puts out a book with recomendations showing how to use their product and it's design limitations. I haven't seen one yet that says it's only for floor use or only for rafter use.
Don't argue with your wife, just dicker
Boss, are the flanges typically larger for rafters?
"...are the flanges typically larger for rafters?"
Nope.
They use the same I-joists for both floor joists AND rafters.
Anglo-Saxon civilization has taught the individual to protect his own rights; American civilization will teach him to respect the rights of others [William Jennings Bryan]
Couldn't you do a scissor truss with different inside and outside pitches and then add a triangular piece (basically half of an upside down scissor truss) to the bottom chord to increase the inside pitch to match the outside? The outside wall would end up taller than the inside wall but it would make a nice clear span cathedral, with an insulation cavity, that matched the outside pitch.
Let me know if that description needs a sketch for clarity.
Golden, they could do those. The added "wedge" is considered a build down and it doesn't have any structural value. They add those types of build downs all the time.
The only reason that someone might want that would be to keep the triangular shaped window parallel with the interior and exterior.
blueWarning! Be cautious when taking any framing advice from me. Although I have a lifetime of framing experience, all of it is considered bottom of the barrel by Gabe. I am not to be counted amongst the worst of the worst. If you want real framing information...don't listen to me..just ask Gabe!
I got no clue what you're getting at. You've confused me more than DW typically does.(-:
Teach a man to fish and you feed him for a lifetime. Unless he doesn't like sushi - then you also have to teach him to cook.
Boss, he's trying to get the bottom chord parallel with the top chord.
blueWarning! Be cautious when taking any framing advice from me. Although I have a lifetime of framing experience, all of it is considered bottom of the barrel by Gabe. I am not to be counted amongst the worst of the worst. If you want real framing information...don't listen to me..just ask Gabe!
See if this helps
Well, I guess you could do that. But it would really cut your wall height down on the inside. And you wouldn't gain any ceiling height.
I've worn G-strings since I left school. And I've never looked back. [Denise Van Outen]
Just exploring ways to get where you guys were trying to go without a structural ridge. I figured the scissor truss and build downs could actually be built as a single truss that would triangulate the loads to free span the width of a room.
The depth of the truss is exagerated in my drawing. I'll bet it could be made a lot narrower, with additional cross bracing, to achieve the effect of I-joists or floor trusses with no need for additional ridge support.
The middle chord, which would be the bottom chord if it was left as a scissor truss, would be the tensioned chord instead of the bottom chord of the build downs. It would transfer the load just like a scissor truss even though the actual top and bottom chords would be parallel to each other.
How much higher the exterior wall vs. interior wall would have to be would depend on the span. If the difference could be kept around 24" it probably wouldn't be a big deal.
"If the difference could be kept around 24" it probably wouldn't be a big deal."
No way would a scissor truss work that was so shallow. Unless maybe you only had about a 15' span or so.
You get too much tension in the bottom chord to have any hope of being able to plate the thing. And as the span got larger, the horizontal deflection would quickly get too high.
You make my life Reflugent.
You make me talk gooder too.
Well, a structural ridge would probably be more affordable anyway.
99% of the trusses we design are steel. Whole different ballgame there...
I did, Deisel, just trying to find time to reply adequately. You had some good questions and I wanted to send some photos to help answer them.
Busy, busy, busy. Hopefully I'll have some time tomorrow while my Seahawks are getting bludgeoned (yet again). Frikkin' Seahawks, man. But hey! How 'bout those Sonics?
Take your time Jim, just wanted to make sure it found it's way home. I was expecting a bit more out of yer Seahawks myself this year.....
Jim,
I know what you mean about the Hawks. I watched the monday night game was was cheering when Alexander ran that TD in the 4th quarter and thought that the Hawks had wrapped this one up. WRONG! Criminy
Sonics though are unbelievable. I keep trying to sit down and wacth them, but miss them. I don't even know who is on the team anymore :-)
Yeah, man, those Sonics are a scrappy bunch this year. We don't get cable but I follow them pretty closely in the paper and on the radio. Just a bunch of blue collar, get after it, love the game bunch of guys (plus Ray Allen).
You get that blade?
I did get that blade. I thought I'd emailed you when I got it, but it must not have gone through. I wanted to thank you for sending that and I haven't forgotten about calling you when we gang cut.
Yeah man, I want to see that, for sure. Port Orchard area? Port Townsend?
Port Orchard.
With the weather the way it is, I'm on different jobs different days, but towards spring or when we get nicer weather, I'll give you a holler (or should I say "hollah"sp?)
Sure you can build a 9/12 - 12/12 scissor (some day I will see if I can spell that). But, duh, that means the outside look is a 12 in 12 pitch. And the entire house would be 12 in 12. So I can see how you can say "you can do anything with trusses" but that does not mean you will like ever archetectual element. (Maybe I will see if I can spell arche . . . too).
"Sure you can build a 9/12 - 12/12 scissor (some day I will see if I can spell that). But, duh, that means the outside look is a 12 in 12 pitch. And the entire house would be 12 in 12. So I can see how you can say "you can do anything with trusses"I never use trusses but that's one thing I don't like about them either in the situation as you said above.Maybe they do make a truss like I drew and if they don't maybe they should try because I think that it's crazy if you want a 9/12 pitch cathedral ceiling that you have to have a 12/12 pitch outside. I personally think that they can't build a truss for any roof that you can stick frame.Has anyone ever seen Octagon shaped trusses or trusses with bastard hips and valleys with cathedral ceilings. When it comes to having rafters with different pitches that call for cathedral ceilings I think it's a problem for trusses. If there's flat ceiling they can adjust the H.A.P. cuts or HEEL cuts with the trusses.Joe Carola
I guess what I was referring to was the open lofts and sloped ceilings on 2nd floors. We do lots of variations on stuff like that. There certainly are things you can do with stick framing that you can't do with trusses. But we sure do some bizarre things with trusses...
We always think every other man's job is easier than our own. The better he does it, the easier it looks.
Blue,
Around here, the builders pay an extra amount per sq/ft of home to stick frame. I'm hourly so I get paid the same either way and I don't recall what the avg price extra it is to stick. I think now it's close to $2 here. Avg per foot framing for subs is around $5 or $6 a foot with stick framing extra.
By the way, wherever possible, we stick frame everything. We use trusses maybe once a year. For us, we can stick frame about as fast as set trusses and we use the extra space as a selling point.
Tim, if I could get $1 per foot to cut a roof I'd be ecstatic. Actually it only takes about a day to cut a roof, and we mess around that much on the truss packaging. The erection process is much faster with trusses though.
blueWarning! Be cautious when taking any framing advice from me. Although I have a lifetime of framing experience, all of it is considered bottom of the barrel by Gabe. I am not to be counted amongst the worst of the worst. If you want real framing information...don't listen to me..just ask Gabe!
I did a whole stick frame roof with i-joists, It isn't hard just time consumming putting in all the fillers ect. I cut a cant strip to set on top of the glu-lam ridge so i didn't have to birds mouth the i-joist at the top and offset the rafters on each side of the ridge and lapped the joist and nailed the piss out of them. when i got to the top with the decking i took my chainsaw and cut off the extra rafter sticking past the lap. I do this with dimmensional lumber also. It saves a lot of time just having to cut the rafter seat and let the top run wild.
cant stripe? Do you mean a triangluar piece to set on top of the glulam to fill the gap between the beam and the angling up portion of the I-joist?
Yes, I would cut a 2x at the rake angle to set on top so the I-joist or dimensional have a nice solid seat to set on. You rip your 2x on edge with a table saw and i put a sub fence on to get that sharp edge. Just lower your glulam a bit and your all set.
Did I hear chainsaw? Does it have an extended table and guard?
Call the Canadiens!
blue
PS I'd do the same with my makita sidewinder....no chainsaws for this crew!
Warning! Be cautious when taking any framing advice from me. Although I have a lifetime of framing experience, all of it is considered bottom of the barrel by Gabe. I am not to be counted amongst the worst of the worst. If you want real framing information...don't listen to me..just ask Gabe!
Blue,
Here is the chainsaw and Headcutter attachment that I use to gang cut rafters. Big Foot tools (http://www.bigfoottools.com) makes it in a 75 and 45° model. It works really really well, although I think that I may modify it a little. http://forums.jlconline.com/photos/albums/userpics/10074/Lot-3-Gang-New-Stihl.jpg
Here is a pic of some of the tools we use to cut rafters. http://forums.jlconline.com/photos/albums/userpics/10074/Picture-017.jpg
You don't need no stinking jig, Freehand.
Tim, I'm not the guy complaining about unsafe practices.....Gabe and others are.
I'm just wondering why they don't crawl out of the woodwork when you are using a chainsaw without a guard.
blueWarning! Be cautious when taking any framing advice from me. Although I have a lifetime of framing experience, all of it is considered bottom of the barrel by Gabe. I am not to be counted amongst the worst of the worst. If you want real framing information...don't listen to me..just ask Gabe!
If you remember i've done a lot of log homes and am very proficent with a chain saw, It just gos faster, no cords and such.
Diamond...and I'm very proficient with my Makita.
To each his own and I say go for it!
blueWarning! Be cautious when taking any framing advice from me. Although I have a lifetime of framing experience, all of it is considered bottom of the barrel by Gabe. I am not to be counted amongst the worst of the worst. If you want real framing information...don't listen to me..just ask Gabe!
I'm in MA and I see 24', 26', and 28' hemfir in 2x6 through 2x12 regularly.
We just finished a house where we used 34' finger jointed 2"x6" rafters.
The longest solid board that we can get is a 22' SYP 2"x6" of 24' SYP 2"x12"
1. Figerjointed rafters? Gee, fingerjointed trim molding is crap, a rafter?
2. Relative to a standard 16 foot 2x12 what will a 24 foot run you?
Finger jointed rafters, hips, and studs.
They used to be real good, but lately I've noticed the quality going down. We have had to start ordering a couple extra because one or to will break. But for the most part they are light, straight and stong. However, I am concerned that we will miss a weak joint until we start decking the roof.
P.S. we don't use the studs very often because they have a tendancy to bow more than a reagular stud. However, they are cheap in price.
Piffin is right about the tji's and stick framinig is always the way to go. I was convinced by others to use trusses on my last house to save time with November coming fast. My goal was to get the framing closed in by the middle of November.
The roof trusses were delivered the day after the first snow storm (only 6") but enough to cause the delivery to be left at the beginning of the 600' driveway. The Wood Structures driver was new and worried about getting in and not being able to get out. My trusses (44' bottom chord) ended up getting frozen into the lawn and I lost almost 4 weeks. This would have been no problem with tgi's or hem-fir. And there is no advantage after. Good luck
Charlie...you were the victim of your own inexperience. We use trusses on 99% of the houses we build and we are very keen on keeping them from freezing in the mud...and when they do, we know how to unfreeze them. (Now that you mention it...I better go check on our pile...it rained for a week and now everything is frozen).
As soon as that pile was dropped 600' away, I'd have hooked my chains up and started dragging them up to the house. I've never met a pile of trusses that I couldn't move with my pickup. Of course, if the pile is large, I might have to take it in stages.
blueWarning! Be cautious when taking any framing advice from me. Although I have a lifetime of framing experience, all of it is considered bottom of the barrel by Gabe. I am not to be counted amongst the worst of the worst. If you want real framing information...don't listen to me..just ask Gabe!
drag your trusses? Gee, are the guset plates worht Crap after that?
"drag your trusses? Gee, are the guset plates worht Crap after that?"
At the first truss plant I worked in, we stacked the trusses on the floor then drug them ut with a forklift.
How much damage it does to the bottom trusse depends on how many trusses there are in the pile, how far you drag them, etc.
It's probably not the best idea in the world, but...
It's often a good idea to let the other fellow believe he is running things whether he is or not. [William Feather]
Well, draging them on a plant floor (assume flat concrete) vs up a 600 foot gravel drive . . .
Just think of it as course grit sand paper. "Rustic" is in you know. You could probably just leave them exposed and everyone would coment on their remarkable character.
Never had any problems....and usually I'm dragging on concrete.
I suppose if I drug them from Michigan here, to Florida...the gussets might be a little scraped up....but hey...I'd be in Florida!
blueWarning! Be cautious when taking any framing advice from me. Although I have a lifetime of framing experience, all of it is considered bottom of the barrel by Gabe. I am not to be counted amongst the worst of the worst. If you want real framing information...don't listen to me..just ask Gabe!
Charlie,
My building project is likely still a way off, but I am looking at stick framing. However, for a bonus room over a 26 - 28 or so wide garage, I was thinking trusses. No good way to stick it without posts and beams in the garage. NO?