Need a book? Engineering books recommendations...

Return to index: [Subject] [Thread] [Date] [Author]

[SEAOC] Structural Observation, Special Inspection issues

[Subject Prev][Subject Next][Thread Prev][Thread Next]
The comments made by Senior Construction Inspector David Owens seems an
unnecessarily harsh indictment of many Professionals for the sins of a few.
Structural Observation is what the City of Los Angeles Department of
Building & Safety settled for following political infighting with the
Inspector Union.  

For a brief window of time following the Northridge event, in the City of
Los Angeles, Special/Deputy Inspectors were required for the nailing of
shear walls over 300 psf.  Our findings have been well discussed in this
forum.  The "This is how I've been doing it for 20 years" attitude required
that we teach AND enforce code requirements not previously enforced. In
defence of the Municipal Inspectors, they have been seriously overloaded and
the situation is worsening even today, but the bottom line is that the
majority of the failures were caused by inferior, even criminal workmanship
that could have been caught by a combination of Inspection and Structural
Observation.  Structural Observation is a valuable program and although it
will not and cannot substitute for Inspection, I believe that given some
time for all to become familiar with the requirements, we will all benefit
tremendously.  When it is mandated, then the competitiveness of the bidding
process is not as heavily influenced, leveling out the playing field.  

This is the spirit of the thrust initiated by Karl Deppe following the
analysis of the investigative field reviews conducted by volunteers from
SEAOSC and the City of Los Angeles.  Special/Deputy Inspectors immediately
were required to know about issues that hadn't been part of our requirements
and for which there wasn't any certification, but some our Engineer clients
took the time to review the requirements with us, teaching us what to look
for with this type of inspection.  Some became a bit more elaborate on their
plans regarding shear wall construction even to the extent of making a
separate page of the plans for the Special/Deputy Inspection requirements,
thereby reducing the number of times the Contractor or persons responsible
for the work would say that they "hadn't noticed" the requirements.  It's
pretty hard to miss when it's a separate page listing the Special Inspection

The requirement for shear wall nailing Inspection was well justified.  There
were some issues that were rapidly being worked out before the program was
canceled for apparent political reasons.  The COLA Inspectors Union
expressed the fear that work was being taken away from them and I personally
was accused of "taking food out of my family's mouth" by at least one
Inspector.  Unfortunately this attitude, based on inaccurate facts, spread
though their ranks and, faced with layoffs, it was a rallying cry for them.
Well, they succeeded in eliminating this program.  At this time, the nailing
of shear walls (actually only a small part of the framing system) is again
not being inspected by anybody, just as in pre-Northridge times.

Of course, the shear walls are inspected after they are completed, but the
issues remain the same.  Nailing requires correct spacing, into the correct
size and grade of framing material, through the correct size and grade of
plywood using the correct size of nails and on and on and on......
Incorrect nailing and re-nailing can easily result in the framing member
exceeding its' penetration capacity which would require the replacing of the
framing member.  So sloppy workmanship in the shear wall nailing can easily
mean that the wall has to come down and be reconstructed and that impact
just spreads.  I've never seen a wall removed because the framing member was
just too shattered or over penetrated although the UBC and LABC are clear as
to the maximum nailing permitted.  Structural Observation requirements do
NOT require the Structural Observer to count nails, measure spacing or
verify that hold downs and anchors are installed correctly, merely that they
exist.  The Insurance carriers of the Engineering community will not allow
Engineers to perform Inspection, and rightly so, requiring they observe for
general conformance to the plans, not a connection by connection inspection.

For the most part, all drilled-in anchor installations are now being
accurately monitored by the Special/Deputy Inspectors as required by the
Research Reports, and the load paths and transfer patterns are being
observed for general conformance by the Structural Observer.  But no one is
verifying the shear wall nailing very closely.

The Inspection Program requirements in Chapter 1 of the 1994 UBC are now
begining to be enforced and I strogly suggest that the Design Professionals
check it out, but that is part of another issue.....

Thanks to Karl for his efforts and now I'll get off my soap box.

R. Sandy Pringle MM 
Structural Inspection Consultants                 "He has achieved success who 
sandyp(--nospam--at)                             has lived well and laughed
Redondo Beach, California