Z-purlin
Z-purlin
(OP)
A client is considering replacing the HVAC on his metal building roof framed with Z purlins similar to the attached sketch.
I would sure appreciate some advice for this, specifically:
A) direction to literature for typical section properties
B) insight as to typical steel grade(s)
c) typical reinforcement details
I would sure appreciate some advice for this, specifically:
A) direction to literature for typical section properties
B) insight as to typical steel grade(s)
c) typical reinforcement details






RE: Z-purlin
AISI has design standards for "Z" members. They fairly complicated and require iteration to come to a solution.
Jim,
RE: Z-purlin
I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.
RE: Z-purlin
RE: Z-purlin
One other thing to note. He has told me before that you need to be careful about LTB with these purlins. He also stated that many building manufacturers never properly accounted for LTB for quite some time (I'm not sure if this has something to do with standing seam roofing or not). This has led to a few problems. One easy way he has corrected the problem when required is by installing 4"-6" steel stud as bridging in-between the existing purlins. Quick easy detail to correct a problem.
RE: Z-purlin
I'll likely have some follow up queries after I've had a chance to digest this excellent information.