Hello. Do you guys ever use a strongback for ceiling joists and have it also double as rafter tie when joists are running perpendiculer to the common rafters and no midspan support underneath the joists?
Thanks
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Maybe you need to define "strongback"
The way I understand it, this would not be possible.
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Hello Piffin. By strongback I mean laying a 2x4 flat on the tops of the joists and nailing the 2x4 to the joists, then using a 2x6 or 2x8 vertical and nailing it to the 2x4 and joists then nailing the vertical 2x into the rafters.
I drew up a crude sketch and attached it.
that is how I would define it.The purpose there is to support the roof by transferring some load to the ceiling joists/rafter ties. That means those need support under them to carry that load to foundation, but if I understand you right ther are two problems here. One is that you have open space with no load bearing walls bloew.
The other is that with the transverse layout, all this would load onto one single ceiling joist, so it would really sag.So far this is a theoretical discussion.
What is your actuall situation and goal?
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Thanks Piffin. It is for a 2 car garage that will be added to my house. Garage is 26'9" span by 23'4" deep. Hip roof over the top (4/12) with the ridge and joists running parallel to the depth.
OK,
Thanks rez
I usually see the strongback under the rafters with the leg extending down to the joists over a wall.With hip roof and running the strongback perpendicular as drawn, maybe it will help. Depends on loads etc.
but a hip roof ought to be able to self support without that.
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This is normal Hip Roof framing. You double your last ceiling joists closest to the rafters and them add outriggers the same size as your ceiling joist nailed to the top plate and along side the rafters with joist hangers into the double.Joe Carola
Joe excuse my ignorance but if I don't use any rafter ties and the ridge does not have any purlins going to any walls to bare some of the roof load won't my walls start to bulge out over time?
My joists are not running parallel to the common rafters.
Is this for the garage we were talking about and the ceiling joists are running the 23' way?
http://forums.taunton.com/tp-breaktime/messages?msg=102000.16Joe Carola
Yes Sir Joe. I'm a visual person so I have been trying to picture what you suggested on framing it. Sorry if I keep asking the same question over and over but I want to make sure I do it right the first time.
I was reading over the post where you mentioned how to frame it using strongbacks and got to thinking if they could be used as rafter ties also.
Does a hip roof by design not push out the walls as much as other roof designs?
Once you get done doubling up the last ceiling joists and nailing in your outriggers and 2-3 rows of strongback, your walls will go nowhere.
Your strongback is holding your double ceiling joists in place and your outriggers are holding your walls in place.
Joe Carola
Joe the light bulb just went off!!!! I gotcha now. Since all top plates will be the same height do you still recommend me using 2x12's to span the 23'?
Thanks again Joe.
Since all top plates will be the same height do you still recommend me using 2x12's to span the 23'?
I've built many 24' garages with 2x8's for the ceiling when it's just used for storage. Is this just for storage? I also work off of Architectural drawings every job and these are always designed and specked as far as what size joists to use.
I use Doug fir fro all the framing. I don't know what kind of lumber you use but, I would try to use at least 2x10-2x12's for that span with multiple strong backs.
You're going to open up the existing wall and sit the ceiling joists on top of the wall? Even if the plates weren't the same height, you bolt a ledger to the existing house and hang the new ceiling joist off that.Joe Carola
Joe it will be for storage only. I spoke to my architect and asked her why there were no specs. on the size of joist,rafters,beams,etc. and she told me my builder would figure that out.
In order to use 2x12's for joists would'nt I need to use 2x12's for rafters also?
If using 2x6 rafters how does one get 2x12's to fit at the ends of the roof when there is a 4/12 pitch?
As far as there other end of the joists, yes I will be opening up the house in order to sit them on the wall.
I spoke to my architect and asked her why there were no specs. on the size of joist,rafters,beams,etc. and she told me my builder would figure that out.
You can't be serious!!!!!!!!Joe Carola
Yes i'm serious. If you look at the attachments I posted in the other post about my garage you will see exactly what she gave me. I scanned a portion and posted it if you want to take a look.
Why do you think i'm here asking about what size of this and that to use.
"I spoke to my architect and asked her why there were no specs. on the size of joist,rafters,beams,etc. and she told me my builder would figure that out."???!!!???!!!That one left my mouth hanging open
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Yes Piffin, that is what she told me. How detailed are "normal" plans?My plans only show elevations and dimensions. There are no specs. in it at all.
each location has the members speced with a note, like "2x6 ceiling joists" or "2x10 floor joists" or "2x8 rafters" or "3/4" deck sheathing" Sometimes something like siding will be drawn one way but with a note saying TBD( to be determined)
Windows should have the RO on plan and a schedule noting exactly which window goes where
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
Piffin here is what my plans look like.
Click here to pursue access to the Woodshed Tavern
Bump.
Wheres the elevation? I've built hundreds of houses with plans like that. To get permits, there has to be a "typical" wall section view. Nine times out of ten, the section view doesn't match the "real" wall section that we will build. The elevation view tells us what the exterior finish is going to look like and we build to that. The truss company designs their trusses to fit to the elevation. In the end, things look like the elevation view and the dimensions of the floor plan guide everything. You're house designer forgot to add the one note that leads us down the path I described. She should have put a note on the plan that said "Engineered trusses or equivalent". That pretty much covers the "details" on most simple homes. Bob's next test date: 12/10/07
Hello Jim. I think you answered my question. Since I live outside the city limits I don't need permits to build or codes to follow so that may explain why she did not put full details into the plans.I did not scan the elevation part.I guess she did forget to put in that note.
Trusses are the answer for you problems
Glad you use 2X8s or more. The strongback here I've heard called stiffener, but that might be something different.I have a "Goodman" home in Plano,TX. Supposedly was a quality builder.Front of home showed a very noticeable sag. When my home was re roofed, I had a contractor build a triple 12" beam across our 22' living room. This is a 22x16 room with 2x6 joists on 16" centers. Home has hip roof with 2x6 that range from a few on 24" centers to more like an average of 28. Rafters that really had no support. He really did a great job and jacked everything up. When I was up fixing a can light that kept overheating, I found another disturbing item. Seems 2 can light lined up directly with the horizontal 2x part of the strongback nailed to the rafters. Apparently no problemo for the electrician, as that was simply cut out in 2 places.Pete, rebuilding one day at a time.Did I mention there is a sag in the ceiling.Having to install a beam in the kitchen now. As the 2x6 rafters on anywhere from 26 to 30" centers caused the 2x4 purling on that side (which was spliced) to give up.
Gotcha, sounds like the same guys that did my house.What pitch is your hip roof?
View Image
Edited 4/4/2008 10:29 pm ET by rez
How long does it take you to open that attachment?
"One for tomorrow. One just for today." Morrison
never did. I went by his text answer. ppt is a DIY cad file I think
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
"ppt is a DIY cad file I think"Even worse. It is a Microsoft power point file..
.
A-holes. Hey every group has to have one. And I have been elected to be the one. I should make that my tagline.
Is this for a hip roof, or a gable roof with the ceiling joist running perpendicular to the rafters?
Joe Carola
Hello Joe, it is for my Hip roof with the joists running parallel to the ridge.
Is there a way to capture that image to be reposted in a jpeg?
"One for tomorrow. One just for today." Morrison
Here is a BMP.
View Image
Edited 4/4/2008 10:30 pm ET by rez
JPG's usually smaller files than bitmaps...
I see it's been done already, but thought I'd answer, for future reference.It's a powerpoint file.Open it with powerpoint viewer. You can get the viewer free at Microsoft's wensite. I don't bother.Anyway, open it with that, and then do a screen capture. I think you kow how to paste that and make it a jpg in your graphics program.
Life doesn't often leave a very easy trail to follow.
Those PPT programs now get opened in my new FREE!!!! "OPEN OFFICE" program. NO MORE MICROCRAPOLA! I love, Love, LOVE Open Office! Did I mention it's free? Bob's next test date: 12/10/07
I see. Use powerpoint viewer instead of just clicking on the attachment and then clicking 'open' in the File Downlaod window that appears.
Edited 4/4/2008 10:27 pm ET by rez
Is this for a hip roof?
Yes, I've done that dozens of times.
Bob's next test date: 12/10/07
Hello Jim. You mean the strongback/rafter tie?
Thanks
Yes. Typically, when I install any conventional ceiling system, I always add some form of strong back. If the ceiling system ties in with a roof in any manner, I typically tie the strongback into the rafters too. This just seems to be common sense to me and creates a slightly more homogenous frame. Bob's next test date: 12/10/07
Strongback and rafter tie
These are two different things and cannot be used interchangeably
meaning you delete the rafter ties because you have a stongback
laying on top of the ceiling joists.