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Re: Standards for Plan Detail

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It would seem that any "standard" as to how much to show on structural
drawings ought to be a thoughtful performance standard rather than a
ritualistic, prescriptive standard. To me, the objective is to show the
drawings user everything structural that I want him to know that he doesn't
already know. The manner in which it is shown I want tailored to not just
provide the necessary dosage of structural information, but to suit the
user's skills and patience, to cater to his willingness and ability to
discover, read, and heed the information. It's a human understanding thing,
not just technical acumen.

The result varies according to the situation, and I don't score many perfect
bullseyes in estimating drawing users' needs. But I do hit the target.

Purposes shared by the drawings creator and all users is that their own role
in the project is easy to correctly fulfill, and that the project is a
pleasant success.

Most of us drawings preparers aren't also drawings users in the same sense
that plans checkers and contractors and inspectors are, but we should do as
much as we can to find out what others need of us and solicit their views on
how well our work has served their needs. When I was starting out in a
structural firm's office, beginners were put to work tracing sketched
sections and details, and also checking shop drawings. I was often baffled
by how shop drawing detailers could tell what was wanted. Finding out where
our drawings gave them their information was my discovery on how to present
structural info. I was placed in the user's shoes, and never lost respect
and concern for that person's needs. 

We designers are users of building code all the time, and have a continuing
experience of being on the receiving end of other peoples' dictates and
presentation style. How easy and how well we find out the info we are
supposed to heed does count for a lot.   

Wood frame construction, especially residential, doesn't generate many shop
drawings, because so little is shop-fabricated or designed by follow-on
specialists. Besides that, woodframing traditionally was left to "accepted
trade standards" (code-covered and a lot more) with only the odd beams and
special elements being specified by a design professional. California public
school designs became a total exception to that following the 1933 Long
Beach EQ. A clash between these two methods, one where the engineer is
incidental and the other where the engineer is paramount, still vexes
codewriters and engineers and litigators.

Showing Simpson hardware in detail on structural drawings was demanded by
the state public school plancheckers in the mid-1970's. I recall drafting
several such connectors on a submittal set of drawings back then, and
gratuitously detailed among them a 16d common nail as well, giving wire
gage, length, required penetration, and a note pointed to the nailhead that
said, "hit this end with hammer," and another at the point that said, "drive
this end into wood."  Our friendly Sacramento checkers enjoyed it immensely,
and sent copies around, but their Los Angeles office admonished them to not
let the design engineers treat them that way.

But I still estimated my local drawing users well enough.

Charles O. Greenlaw SE   Sacramento CA