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Re: Member sizes for joists

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There are no "standard" sizes for the individual pieces of hot- or cold-
rolled steel that make up a steel joist.  

The SJI specifications are a performance spec, rather than a
prescriptive spec, leaving each manufacturer a fair amount of latitude
in their design.  Different truss geometry, including such variables as
warren vs. modified warren, panel size, number of panels, bearing
details, and even the use of unequal panels, plus other items such as
chord splicing, rod bending, web crimping and joint welding techniques,
can result in trusses with different material having the same strength,
or vice versa. 

Despite the other response, chord sizes vary from 2-L1x1x0.109 up to
2-L4x4x0.375, and occasionally larger.  Webs range from 0.500 round bar
to 1.125, and 1-L1x1x0.109 to 2-L3x3x.0375 or more.  And that doesn't
even begin to cover the range of cold rolled sizes, some of which are
proprietary.

If your client is trying to estimate the final weight of a bunch of
joists, I suggest you use the approximate weights published by the SJI. 
If, however, they are planning to fabricate joists themselves, I suggest
they learn how to design them first, and then answer the question
themselves.  Your question implies a customer that is in the process of
getting in way over their heads, without proper help or education.  Good
luck.

Phil Hodge
phil(--nospam--at)joistdesign.com