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IBC vs NFPA5000 (Was IBC 1617.6.2...)

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Just out of curiosity, some are talking like the IBC is a done deal in
California.  The NFPA5000 is due out around June and since it is backed by
the Unions do you think Governor Davis would ever allow the IBC, especially
with all those scab contractors installing plastic pipe ??

Thomas Hunt, S.E.
Duke/Fluor Daniel

                    "Barry Welliver"
                    <barrywelliver2@eart       To:     <seaint(--nospam--at)>
          >                 cc:
                                               Subject:     RE: IBC 1617.6.2 & IBC 1617.6.3--1997 UBC 2320.2 & 1605.2 -
                    02/11/02 04:38 PM           how to tell if your plan reviewer is really looking at the plans
                    Please respond to

I applaud this type of discussion because it shows how necessary it is
becoming to interject the "engineering" point of view. We have a new
International flavor to our building codes and it will take some years to
get it right.

For the immediate future however there is a complicating issue that we've
all grown to dislike...liability. We tripped over this with rigid/flexible
diaphragms and certain motivated professionals helped to grind out a
solution. We'll need to do this with the IBC/IRC if we hope to avoid

I happen to think that the IBC is a worthwhile effort. It presently has
of warts (well, maybe not lots) and will take cool heads to bang out a
solution. I don't think that this will be a smooth road to travel either.
For most of us it's going to take a lot of relearning and a motivation to
make it right for reasons beyond just our own points of view.

Dennis, you mention the next cycle of the IBC which is 2003 and how it will
address some of Scotts issues. Can we air some of those here such that we
can vicariously participate in the process? I believe the code change
process could use as much input from engineers at this point as from

Lastly, I concur with the perceived conclusion that the Building Officials
are being put in a very awkward position. They will need encouragement and
whatever help available to make this work. We are asking too much if we
expect the BO to have instant fluent understanding. Indeed, enforcement of
the code is a balance of legal prescriptions against logical
interpretations. In the absence of a wealth of consensus, it is still thin

Barry H. Welliver

> -----Original Message-----
> From: Dennis Wish [mailto:dennis.wish(--nospam--at)]
> Sent: Monday, February 11, 2002 3:54 PM
> To: seaint(--nospam--at)
> Subject: RE: IBC 1617.6.2 & IBC 1617.6.3--1997 UBC 2320.2 & 1605.2 - how
> to tell if your plan reviewer is really looking at the plans
> Scott,
> I absolutely agree with you as far as the prescriptive methods of
> design. A lot of your concerns are being addressed in the 2003 IBC which
> will be the IRC, however, the root of all of the issues will not be
> resolved - how do you educated a designer or builder as to the
> interpretations of the prescriptive method when few of them own or have
> read the building code section.
> Most rely upon a rudimentary plan review where the technician (who is
> generally not an engineer or architect) will make his or her own
> interpretation of the code. Who then will insure quality of
> construction?
> The answer, while obviously the Building Official, is also without
> liability for making mistakes and there is no law governing the
> unlicensed to prevent them from making mistakes that leads to poor
> quality of construction or defects.
> Without certification of those designing or building structural systems,
> the code is nothing more than an unpopular book with few readers other
> than those that are mandatory for those with licenses or titles.
> Personally, I think we have made a royal mess of things and few are
> willing to try and stop evolution in progress - there is too much at
> stake and the public will be the losers.
> The issues related to Simplified Static principles are not a local code
> - it still must be a structure without irregularity. However, in my
> area, most buildings are one story and can be modified as needed to
> comply with regularity in design.
> I think my point was more to the fact that we have stopped using our
> intellect and have gone out on a limb seeking perfection over
> practicality. Consider, for the moment, that home which was designed
> using full-compliance (including rigid diaphragm analysis) in ten years
> when it is sold and the new owners want to remove a few walls, add a
> room, push out a window, or any of a thousand things that homeowners are
> likely to plan when they purchase a new or existing home.
> The difficulty in tracking the load path and recreating the lateral
> resisting system of the building in order to re-balance or add (remove)
> shear will be next to impossible. Certainly not as rational or easy  to
> do as it is with flexible and tributary analysis.
> While FEMA 268 and 302 state that a wood structure with a wood diaphragm
> acts rigid, my response is who cares. Is there any real evidence that
> the lack of additional restraint for those forces distributed through
> the diaphragm have caused damage in homes? The answer is that we don't
> know, have not done any more work in finding out and have published
> nothing of consequences on the subject since Northridge. If you ask the
> NAHB then the answer is absolutely not - homes did what they were
> designed to do - protect the occupants and if they were damaged - so
> what again? The owners of these homes were to blame because their
> expectation of performance was unreasonable to begin with.
> I don't buy this cr*p. However, I also don't buy creating a design
> methodology that makes it impractical to change a home after it has been
> constructed unless the original drawings and analysis are available to
> understand the engineers intent.
> I think this is the main reason why building officials are willing to
> accept what an engineer has to offer as in the end, it should be left to
> the discretion of the EOR.
> So much for my own Diatribe!!!! >)
> Dennis S. Wish, PE
> California Professional Engineer
> The Structuralist.Net Information Infrastructure
> Website:
> ."The truly educated never graduate"
> -----Original Message-----
> From: Haan, Scott M. [mailto:HaanSM(--nospam--at)]
> Sent: Monday, February 11, 2002 2:21 PM
> To: 'seaint(--nospam--at)'
> Subject: RE: IBC 1617.6.2 & IBC 1617.6.3--1997 UBC 2320.2 & 1605.2 - how
> to tell if your plan reviewer is really looking at the plans
> Dennis:
> I was wrong on a few points about the IBC in my diatribe about UBC
> requirements design of portions and combination of R's on the same axis.
> IBC 1617.6.2 & IBC 1617.6.3 allows you to vary R's from grid to grid for
> houses and duplexes.  Also IBC 2308.12 says you can design a portion of
> an
> unusual house.  If it is the local code down there - more power to you
> guys.
> I would consider that if someone brought it up on one of my permits.
> Personally my loyalty is toward the profession and not toward enjoying
> the
> thrill of ruining a person's day.
> On the flexible diaphragm thing: FEMA 368 Section and FEMA 302
> Section say that wood diaphragms on light frame walls should be
> considered rigid. I once got chewed on by someone on your list for
> suggesting that I had never seen a wood building design using rigid
> diaphragms. I've seen that LADBS Document P/BC 2001-03 that saysou could
> use
> the "simplified static force procedure" and assume flexible diaphragms
> until
> other research comes out.
> The problem with prescriptive methods, locally at least, is that nobody
> has
> ever bothered to understand the code provisions and most people think
> that
> prescriptive design =no design & nothing shown on plans.  There are
> specific
> layout rules and the stuff should be shown on plans.
> The problem with the new IBC [not IRC] code language is that it says
> buildings of unusual shape can have the unusual area designed. 97 UBC
> 2320.5.4 said design the entire building if it is irregular, and UBC
> 2320.2
> "design of portions" was meant to apply only to regular [not irregular]
> buildings where grids do not have enough bracing ect... The end result
> is
> you are moving towards everything = prescriptive = no design.  It leaves
> the
> opportunity for  dumb ideas like: if I have cantilevered columns on the
> first floor can I design them for the capacity of two gypsum board
> shearwalls because that is all that is required for a prescriptive
> house.
> The IBC puts the onus on the BO to prove that a building is not
> prescriptive
> and to prove when an unusual shape exists and then to argue that one
> part
> has to be designed.  This stuff should be considered before a permit is
> applied for and it never is here.
> Respectfully,
> Scott Haan

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