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RE: Lag screws in withdrawal from end gr

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I was a member of the (then) Hazardous Building Committee under Dave
Brieholtz PE. One of our chores was to proof read the final draft of the
City of Los Angeles RGA Provisions (Unreinforced Masonry Retrofit Code).
Half of the difficulty in the final stages was to determine which word was
appropriate and which would cause the least confusion. These included words
of intent such as *will* and *shall*. I don't think any of us actually
figured out what was appropriate since each had a connotation that created
potential confusion. Our opinion was that if it does not say *Will*, *Shall*
or *Must* then the subject is open to some interpretation and the engineers
judgement comes into play. The words *Should* and *May* are such words that
allows interpretation - *if the engineer can prove an acceptable

For this reason alone, I gave the members of code creation committees the
greatest kudos for their efforts. If I recall, this was the last meeting I
attended before leaving for the desert. I doubt that I would have continued
on the committee through this phase of code developement since I found it
most frustrating.

As an engineer, I soon learned that virtually nothing is carved in stone.
The code is a guidance for professionals that outlines an acceptable
standard. As we have debated, it is also a minimum standard intended for
non-professional to follow (Conventional Framing). It has been my experience
that alternative methods are allowed if the engineer can justify his work.
One example: I was providing the City of La Quinta plan check services for
the famous La Quinta Hotel - an eighty year old (or older) adobe structure.
The engineer who designed the retrofit did not work from the typical code -
a working stress methodology. Instead, he used an ultimate strength method
that I was not familiar. The engineers credentials and reputation with
unreinforced masonry and Adobe was unquestionable. Although I needed time to
compare the results, it turned out to be comparable, albeit slightly less
restrictive, than convential code. The local building official was willing
to accept the engineers work considering the historic value of the structure
and the need to make the work invisible to the public. I suggested some
minor changes regarding secondary suppports that included some decrative
corbles and heavy timber in order to maintain the aesthetics of the building
and the work was permited.

The point is that we need to be creative and our creativity includes our
engineering judgement. Engineers are not simply math crunching scientists -
we are part of a very creative field. Therefore, we need to be willing to
step out on a ledge at times in order to solve a problem. Codes are not
meant to create one solution to a problem. They are simply guidlines to
follow. Most structures lie somewhere in the grey area's. This is where
creativity and judgment go hand in hand. Even a creative solutions can have
conservative results. This is what our clients expect of us and probably
annoys the hell of of most plan check engineers:>)

Dennis Wish PE

-----Original Message-----
From: Bill Allen, S.E. [mailto:bill(--nospam--at)]
Sent: Tuesday, September 08, 1998 2:10 PM
To: seaint(--nospam--at)
Subject: RE: Lag screws in withdrawal from end gr

I guess building codes need to be more directive by using the phrases
"shall" and "shall not" since we engineers are incapable of properly
interpreting the intent of the phrase "should not".

Bill Allen

-----Original Message-----
From: ErnieNSE(--nospam--at) [mailto:ErnieNSE(--nospam--at)]
Sent: Tuesday, September 08, 1998 11:58 AM
To: seaint(--nospam--at)
Subject: Re: Lag screws in withdrawal from end gr


I still want to know why they used the word "should not".