Truss camber
Truss camber
(OP)
We have a 123 ft. long by 10 ft. deep steel truss. The customer drawing specifies the required camber at each of the panel points. How does one go about fabricating the truss with the camber in place? Step by step instructions would be great.
Thanks.
Thanks.





RE: Truss camber
Simply snap a straight line at the bottom chord and measure up at the panel points. Build the truss following these new points.
RE: Truss camber
RE: Truss camber
RE: Truss camber
I note that you are a new member, but you are getting off on the wrong foot by commenting on an old thread that "Actually this isn't true." The thread is about a long span steel truss, thus your post makes no sense.
RE: Truss camber
RE: Truss camber
RE: Truss camber
RE: Truss camber
(Floor trusses,Wall panels, Roof trusses etc...) for the last 12 years. Familiar with Many truss tables and multiple software programs.
RE: Truss camber
The reason for camber is deflection and wood creep. Creep will happen over ten plus years. Now you can build the trusses flat and have a sight downward bow in the ceiling from day one and let it creep down. You can use camber for a flat ceiling from day one and then let it creep. Or you can use camber for a upward ceiling from day one so that it will be a flat ceiling in ten years.
As for software programs, when camber was wanted but could not be inputted into the program, typically the manufacturer cut the webs a 1/8" to 1/4" short to camber pitched trusses. Flat trusses were just "bent" in the jig for camber.
Garth Dreger PE
AZ Phoenix area
RE: Truss camber
and The IRC 2009. In those you will also find that Truss designers and Manufactures are not responsible for a whole array of things that the Engineer of record is. Now if you think that trusses "Creep" at 10 years you are a Magician!
I suppose you recommend nailing the bottom chord of the trusses to all interior walls also?? Then you will wonder why their are excessive drywall cracks and in some instances walls literally seperating from the subfloor.
I suggest visiting a truss line and look at the Steel table in which they are built, notice it is straight. Now try to "bend" the trusses. I can design the trusses you mentioned with Minimal LL and TL deflection and NO bracing, but you won't like the Price.........So end of discussion for me, some people just like to argue a point in which they don't have hands on experience with.
RE: Truss camber
1) Design wood trusses (off and on) since 1984 and sealing them since 1992.
2) I understand the CYA that the WTCA, TPI, etc. states about the responsibility for wood trusses.
3) If you read my note I said "...camber is a judgment call (based on what their clients want)..." The clients being the framers who have to deal with the callbacks on their jobs.
4) I have also gone out to jobs (not many, but a few) ten years down the road and have seen the creep in the ceiling.
Garth Dreger PE
AZ Phoenix area
RE: Truss camber
RE: Truss camber
Garth Dreger PE
AZ Phoenix area
RE: Truss camber
Not your fault, and no apology necessary. Your comments were entirely appropriate.