As the title says have any of you done it. Most manufacturers say there product can be used for stick framing a roof. I have a project coming up this spring/summer. A 28by 44 foot ranch with two bedrooms and a bath upstairs in the attic space. The house will have two dormers one per room and a shed roof to go out to the porch. What I am thinking of doing is framing a complete floor deck on top of the first floorwhich will give me a great working space. The added height of the floor will act as an “energy heel”walls the entire footprint of the house. This way I will be able to snap out my gable walls and my rafters on the floor. I will make the heel cut 3 1/2 like it was sitting on a 2by wall. Eight foot up I would use probably more Nascor 12” I joice as collar ties on every rafter. The side walls of the rooms will be 7′ high so the I joice wont be spanning that much. What do you guys think. Have any of you used any type of I joice for roof framing. I like nascor because I can get it pretty easy here. and Being flat with 2by3’s you could use them as a collar tie also. (I have looked into the appropriate web stiffening info)
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I've done the same thing you're thinking about Kayaker. It works great.
blue
"...if you just do what you think is best testing those limits... it's pretty easy to find exactly where the line is...."
From the best of TauntonU.
Thats good to hear. With I joice or the floor deck. or both. What I joice. sorry for all of the q's
Oops, I forgot about you mentioning that you wanted to use I joist. I used regular ol' dimensional lumber and a few key microlams.
Your I joist will work perfectly though and it's a good idea when you're trying to create alternate designs off simple box structures.
blue"...if you just do what you think is best testing those limits... it's pretty easy to find exactly where the line is...."
From the best of TauntonU.
There have been a lot of threads about this - Searching should bring up plenty of them.
You cannot preserve the rule of law by surrendering to force or the threat of force [Charley Reese]
Spelt ....JOIST!
"If 'tis to be,'twil be done by me."
If you come across any of them please send them my way I searched for a while with no luck.
Are you dead set on I joists? They may be the same price as lumber but the hardware and the extra time involved in the birdmouths reinforcement would change my mind.
What pitch is the roof? I can get 22' yellow pine 2x12's here in Battle Creek they are a stock item. For a 12/12 pitch 20' will get you to the plate line.
I am not dead set on I joist but would really like to try them. The pitch is 12/12. If I was to use dinesinal lumber I would use 2 pieces of 2 by for every rafter and lap them at my room walls That are 7' high. But that would not be as eazy as framing it all with I joist and framing in my "1/2" wall latter.
Why would you splice the rafters if you used lumber? When you can buy full length rafters. Big C in Schoolcraft probably stocks them also.
It's on sale even.
http://www.taunton.com/store/pages/070781.asp
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Joe H
Good option Stilletto.
Are the yellow pine stock good stuff? I've seen a lot of yellow pine heave considerably because of knots midspan. I've also seen a lot of nice #1 yellow pine used for tread stock. I'm just curious about the quality of your rafters. I haven't seen anything like that on jobsites. We use doug fir for that.
blue"...if you just do what you think is best testing those limits... it's pretty easy to find exactly where the line is...."
From the best of TauntonU.
The yellow pine that is available at that particular yard is good, the majority of them are good and straight. If you get a few that you don't like on a load they will replace them until you are happy. We use alot of it for headers, stringers, porch and valley rafters, floor joists.
we use i joists for rafters on about two houses a year. we cut them with no birds mouth, just the plum and level cut, then pad out the middle of the joist with 1x for about 6' up the rafter from the outside wall and scab tails on with conventional lumber. it works great, although i think it's excessive in htis case, not worth the extra work,ie. hardware and labor.
I would be interested in trying an I-joist roof after they have been in the field a while longer. I have never been a big fan of them. And in fire cases they go up in flames in a hurry. We are talking total failure in no time.
Maybe I am being to skeptical about them. I have always ordered yellow pine when I was cutting a basic roof. I can readily get them up to 22' long and they have been in the field a long time.
Sistering tails and adding blocking are steps you don't have to take with 2x12's. I don't cut many roofs, so my opinion on this isn't worth alot.
My inspector is clueless and very hard to deal with so in my case I would have to sit down with him before I even tried I-joists in a roof.
Sistering tails and adding blocking are steps you don't have to take with 2x12's
We didn't sister tails, but we did add 2x4 blocking to the tails for the fascia and closed soffitt
http://pic40.picturetrail.com/VOL293/2163851/11350387/164183310.jpg
http://pic40.picturetrail.com/VOL293/2163851/11350387/164183298.jpg
http://pic40.picturetrail.com/VOL293/2163851/11350387/164184922.jpg
You have done both which do you prefer to use? Rafters or I-joists.
Are you confident in the I-joists holding up?
They each have their benefits. For longer spans, I-joists are nice. I'm talking lengths over 24' because that is what we can get easily. For a simple gable roof, with lengths lets say 28', I'd pick I-joists every time. I think they'll hold up just fine. They've been used in floors for a long time now, and used for roofs too. There are some JLC articles about using them for roofs from the early 90's.
By the way, for this roof http://pic40.picturetrail.com/VOL293/2163851/12448759/195441153.jpg stick framing materials including fascia, ply, fly rafters etc was 2k cheaper for us than trusses along (not including fascia ply flyrafters etc). We subbed this job a year and a half ago and trusses were a lot more. This roof was all 2x12 rafters, 2x8 ceiling joists, and 2x8 rafters in the garage.
Incidentally, our cost to frame the house was about 2k cheaper than the sub even factoring in that we are hourly (all the taxes and benefits) and the forklift.
In our area, it is rare that trusses are the less expensive materials. Although that I-joist roof was. But that was with a 6 3/4 x 18 and 6 3/4 x 19.5" glulams each about 32' long :-) If we could have gotten an intermediate support in there, which we will if we ever do this again, we could have saved more $
You have alot more experience with rafters than I do, so your opinion matters to me. Maybe I am just a little too skeptical with some of the newer products out there.
$2,000 cheaper is a good savings that early in the project.
If you want to use I-joists the supplier will usually engineer the whole deal for you for free.
OTOH, for the size of the building you describe, do you really need I-joists? They can get pretty pricey...
They come out to the same price as lumber but will all of the advantages,straight,straight,straight,and straight, as well as my rafters being one piece.
Kayaker,
Check out the "Advanced Framing, Techniques, Troubleshooting and Structural Design" by Hanley Wood. (JLC Books) There is a whole chapter (3-4 pages) on using wood I-beams for roof framing. Personally I have never used them but I intend to. (I am building a real energy efficient house and they are the only way I could do my roof the way I wanted) But anyway, I digress. The book addresses most of your questions I am thinkin. Good luck!
KD
I-joist suck for roof framing!! have to use to much hardware and have fun nailing on fascia!! also i haven't seen an I-joist that your were allowed to cut abirds mouth into?
I agree, I wouldn't use them for framing a roof if I could avoid it. He asked if it could be done, not if it should be done. There's a difference!
Just because it can be, doesn't mean it should. That's one of my past mottos. I still live by that credo.
blue"...if you just do what you think is best testing those limits... it's pretty easy to find exactly where the line is...."
From the best of TauntonU.
Ditto here.
Did a big one a few years ago w/ (if memory serves ) 40' span or so cathedral ceiling. The hangers had something like 30 or 40 nails per. Thank god for palm nailers.
Would be worth some additional research on the op's part though. Had a case like this before and was told that under no circumstances were ceiling joists to be attached to the sides of I joist roof rafters, as in a "collar tie/ ceiling joist. Was told at the time by I joist mf. and lumberyard sales that, although the question arose once in awhile, loading, attachment etc. were not approved for that application. ( Don't get me wrong, I think common sense would dictate that with some padding/fillers and good attachments, this would be perfectly ok).
Maybe some engineers have done the math since then, and now it's copisthetic. ;)
Bing
Thanks for all of the posts guys I will definitely check out that book. I probably could get that lumber full length, I just wonder if I would pay a premium for the length.
Yes, you pay premium for premium lengths. It's still a lot cheaper than I joists though.
blue"...if you just do what you think is best testing those limits... it's pretty easy to find exactly where the line is...."
From the best of TauntonU.
There is another option that will save a Lot of time. Attic trusses!!! Probably the same cost as I joist and a lot less time. another option.
That was going to be my next question, if you thought about attic trusses. You would have to stickframe in between them for your dormers but that is no big deal.
I think the price of trusses would be really close to the materials for stickframing your roof.
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Yeah My only thing is do I set attic trusses on 2' centers for the roof and perlin the floor, 19.2 centers and meet in the middle or 16" centers and really beef it up. I am going to go to the lumber lard monday and have a truss guy give me some info on attic trusses for my aplication and have the Nascor rep figure up my roof to with the I joist. I will be able to see the price on both and all of the special attention needed for the I joist.
We have a plan (Mascord) that we've built 3 times. Last summer was number 3 and we decided to stick frame the roof instead of trusses. There was so much room in the attic that was unusable. So we went with I-joists for the roof.
We were dealing with one company because they had LSL rafters and we wanted to try them, but not at $6/foot!! so they designed the roof for I-joists, but picked the biggest joists you can buy before switching to a commercial joist. So we switched back to the normal company we use.
We ended up using 11 7/8" I-joists, and because we had kneewalls inside, we could break up the span. The first company wanted them clearspanning. Anyway, long story short, we nearly doubled the square footage of the house, added 1 bedroom, 1 full bath, kitchenette, and so much storage its not funny. The I-joists were easy to work with. We did not cut birdsmouths, we beveled plates and glued and nailed them down on the ridge beam and the plates. I tried to avoid using I-joists hangers as much as I could because they were $50/peice.
If I remember correctly the package was about $1500-2000 more than the trusses, but for nearly 2000sqft more it was worth it (add in the floor price and the framing and it was much cheaper sq ftage than the first floor).
Here is a link the photo album of that house. The pictures of the cedar arbor are from yesterday.
http://www.picturetrail.com/gallery/view?p=999&gid=11350387&uid=2163851
That looks like sooo much fun (as long as the weather is nice) Did you consult the I joist rep with that job I noticed that you had no web stiffeners at heel area of the joist. I will look into the tji's. Framing it like you did would not really require any more work than conventional lumber. (Trade off all little detail here and there for being able to clear span the rafters it is probably the same ammount of work) I just dont have the cool chainsaw cutting tool yet........
No web stiffeners were required at the bearing points. We rarely have to put them in. We use Roseburg joists and we get it all designed. On that job we used TrusJoist for the first and second floor and were supposed to get a deal on the roof too . . . .
They wanted webstiffeners on the joists, but their rim was rated 1000-1500plf higher than the typical Roseburg rim we get. I asked the rep why. He didn't have an answer. The rep for Roseburg said that there was no need. I mean they had us put stiffeners in on a small section that only supported one wall, no second floor load. That was indicative why we switched.
Anyway, we did have to put in blocking at all bearing walls, but no stiffeners. We don't have much loading here where we are on roofs. I forget, but I think the total loads on roofs are about 45lbs/foot, 30 of which is live load.
I would set the trusses on 16" OC. Attic truss floors are usually springy at 24" OC. Then you wouldn't have to use plywood clips on the roof either.
It's a few more trusses but in the end everything will feel solid.
If you don't like the price of attic trusses you get I can call my truss designer and see what he can do for you.
"Attic truss floors are usually springy at 24" OC."
I've only done 3 buildings with attic trusses, but have never had any trouble with the floors at 2' O.c.
I wonder if it's the plywood you're using?
It could probably be shown by facts and figures that there is no distinctly native American criminal class except Congress. [Mark Twain]
I think my truss saleman is awesome, he quoted me a price for 42' scissor trusses for $100 each the other day. His prices are alot better than other companies that sell them around here.
As far as the cost of attic trusses I can't remember what they cost me a piece on the last job. But they are going to be close. With attic trusses you don't have to buy floor joists, rafters or sidewall studs and plates. Or the labor involved in stick framing it.
I use 3/4 T&G OSB on the attic truss floors glued and ring shank nailed. It just feels soft to me, maybe I am just looking too hard.
"I think the price of trusses would be really close to the materials for stickframing your roof. "
Any good truss salesman would tell you that. But I'm not a good salesman.
(-:
Preces vary a lot from one manufacturer to the next, but attic trusses are almost universally expensive. I'd venture a guess that attic trusses would be double what the lumber would be. (Maybe more)
There could be savings from not needed interior beams that would offset some of the cost. And there would certainly be less labor.
How it would end up overall is beyond me - I've never tried stick framing an attic.
Nothing is wrong with California that a rise in the ocean level wouldn't cure. [Ross MacDonald (1915-1983)]
i haven't seen an I-joist that your were allowed to cut abirds mouth into
You can cut a birds mouth into TJI's. Details are on page 7 or 8: http://www.bc.com/wood/ewp/documents/western/west%20install%20guide.pdf
Beer was created so carpenters wouldn't rule the world.
thanks guys for the info I will keep lookin
Let us know what you decide on, I'd like to see how the prices for each add up.
I've only been in on two roofs where we used I joists, both large cathedral ceilings. Like 'em or not, an I joist provides more room for insulation.
Beer was created so carpenters wouldn't rule the world.
"i haven't seen an I-joist that your were allowed to cut abirds mouth into?"
I haven't seen an I-joist manufacturer yet that would NOT allow you to cut a birdsmouth.
Last night I stayed up late playing poker with Tarot cards. I got a full house and four people died.
We have used I joists in similar situations. That is, where there is a very long rafter with either a steep pitch or supporting walls. I would never use I joists where I didn't need to because of the extra hardware and stiffeners that are a considerable extra expense but when you need a 30 ft or longer rafter, I joists fit the bill nicely.