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RE: ICC / ICBO Reports

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Building Officials sometimes promote bureaucratic sloth. Governmental indolence leads them to ask for ICC reports when first principles are adequate. I get it all the time.
 
A typical application for a report is where values are based on testing rather than theory. This makes sense since no one wants to do testing every time a product is specified. But, you are right, it makes no sense when calculations will cover the issue. There are also cases where there is no design specification covering the particular product. Corrugated steel deck is such a product when it comes to diaphragm shears (and vertical loads on composite deck.) Of course, even in that case there are empirical equations.
 
Mark E. Deardorff, S.E.
Structural Engineer
Burkett & Wong Engineers
3434 4th Ave
San Diego, CA 92103
P 619.299.5550
F 619.299.9934
mdeardorff(--nospam--at)burkett-wong.com
 


From: Charles R. Ashley Jr. [mailto:charles(--nospam--at)advanceeng.net]
Sent: Friday, June 22, 2007 9:09 AM
To: seaint(--nospam--at)seaint.org
Subject: ICC / ICBO Reports

I am looking for some clarification on ICC (formerly ICBO) reports.

 

I will start by stating my understanding:  These reports are provided as evidence that an item whose manufacturer says is worth X is actually worth X.  This permits the EOR to use said item without providing calculations justifying its use.  In fact, they permit the layperson to use the accompanying tables and charts to use in the design of their own projects.  Is this not their purpose?

 

Therefore, ICC reports are NOT required in order to use a product or material on a project.  Just helpful.

 

So why does it seem it is getting harder and harder to get bldg. depts. to look at new products without ICC approval even though they have engineering calculations to back it up?  And why should an ICC report limit my use of particular product in a manner that I have determined (using engineering principles and lots of common sense) is acceptable just because it doesn’t meet the exact conditions listed in the report?

 

Why am I forced to use a factor of safety of 4, when I would be comfortable with 3 in certain situations?  Who decides these factors of safety anyway?  It seems ICC is choosing to do that through the reports: is that appropriate?  Why then aren’t these factors of safety mandated in the codes?

 

Here’s where I think the system has failed: it’s the “one size fits all” mentality.  As mentioned earlier, the ICC reports were intended (as I understand it) to permit the layperson to use an engineered product under very specific conditions and with significant limitations.  By dumbing it down to fit that denominator, and then applying those same restrictions to engineers, is flawed thinking.

 

Here’s a great example: Most insulated concrete forms (ICF) are approved only for residential use, and only up to 8ft or so.  So I recently had to argue passionately convince a plan checker that this did not preclude me from using it on a commercial project with much taller walls.  It’s just a forming system!!

 

Does giving that an ICC # really mean I can’t engineer something without ICC blessing?  I know that is not the intent, but it sure seems that is where we are headed.  I mean, ICC already gave me a number (PE# 63103 in CA) so shouldn’t that mean something?!

 

Now, to switch hats, I obviously see the value in having a central organization to review products on our behalf.  I am not arguing the merits of the system.  I am just asking if it is being used appropriately.  And, we all have run across engineers who need someone else to think for them.  Again, the system has its place.

 

I am looking for other thoughts on the subject.

 

Charles R. Ashley Jr., P.E.

ICC-Approved Professional Engineer